Vision of the Mechanical Engineering department

Transforming young minds into motivated, quality aware and environment - conscious technocrats.

Mission of the Mechanical Engineering department

Educating the students to excel professionally by:

Providing facilities and environment conducive to a high quality education.

Cultivating the spirit of entrepreneurship, applied research and responding effectively to the needs of the industry.

Emphasizing the values of leadership, contributing to economic development, protecting the environment and improving the quality of human life.

PEOs of Mechanical Engineering Department

After 3 to 5 years of completion of the graduation, our graduates will be able to:

PEO 1 Enhance Professional Capability They will apply mathematical, scientific and engineering principles for analyzing and solving mechanical engineering problems.

PEO 2 Excel Technically and Foster Continued Learning They will be competent to design and develop meaningful solutions for efficient utilization of man, machine, money and materials, using modern techniques and tools and nurture continuous learning.

PEO 3 Address Social, Ethical and Environmental Concerns They will deal with social, ethical and environmental concerns in technological advancements.

PEO 4 Enrich Essential Management Skills They will augment management skills along with teamwork and effective communication for successful completion of engineering projects.

Programme Outcomes

1. Apply knowledge of mathematics, science and engineering fundamentals to the conceptualization of science and engineering models.

2. Identify, analyze, formulate and research literature to interpret data for Mechanical Engineering problems using first principles of mathematics and engineering sciences.

3. Design solutions for Mechanical Engineering problems and develop systems, components or processes that meet specified requirements

4. Conduct investigations, analyses and interpretation of data and synthesis of information to arrive at valid conclusions to complex Mechanical Engineering problems

5. Demonstrate skills to select and apply modern engineering tools, understanding the constraints, using appropriate techniques

6. Demonstrate understanding of the societal and legal issues and the consequent responsibilities relevant to engineering practice.

7. Understand the impact of engineering solutions in an environmental context and demonstrate knowledge of and need for sustainable development.

8. Follow professional ethics with consequent responsibilities relevant to norms of engineering practice.

9. Perform effectively as an individual, and as a member or leader in diverse teams, in multi-disciplinary settings as well

10. Communicate technical ideas effectively with the engineering community and society by oral and written means.

11. Manage a project effectively, understanding the limitations of general business practices including risk and finance management

12. Engage in independent and life-long learning to meet global technological challenges

Mechanical Engineering Department of Saintgits College of Engineering have immense pleasure to unveil the fourth edition of Technical magazine for the academic year 2014-2015, presenting high quality works in an accessible medium for use in teaching and future research.

This magazine is a small step towards emphasizing the values of leadership, contributing to economic development, protecting the environment and improving the quality of human life.

The magazine organizing committee extend deep hearted gratitude to our Principal, Head of the Department, College management and beloved colleagues for their support, cooperation, constructive suggestions and healthy criticism with a view to enhance the utility of the magazine.

Mechanical Engineering DepartmentJune 2015

CONTENTS

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LOOP HEAT PIPE Githin V Sam, Jesvin Sam, Jethin Babu, Jithin Victor A NOVEL METHOD FOR SPACE COOLING FROM AUTOMOBILE ENGINE EXHAUST Jesti n James, Jomy Jose, Anoop Vi jayan, Boney Thomas Varghese

PHOTOVOLTAIC DRIVEN THERMOELECTRIC REFRIGERATOR FOR CAR HEAT DISSIPATION DURING SUNNY DAYS Ashiq Georgi Abraham, Bobby Jacob, Davie George Vinu, Dean John Vinu EXHAUST GAS WASTE HEAT RECOVERY AND UTILIZATION SYSTEM IN IC ENGINE Alvin P Koshy, Bijoy K Jose Jeffin Easo Johnson, K Navaneeth Krishnan, Bijeesh P STUDY, DESIGN AND OPTIMIZATIONOF TRIANGULAR FINS Abel Jacob, Gokul Chandrashekhara, Jerin George, Jubin George STEAM TURBOCHARGING Abhijith P, Akhilesh Rajan, Cyril Soji Thomas, Kevin George Jacob REFORM THE PERFORMANCE OF A BILLET QUALITY BY REDUCING ITS DEFECTS AT SAIL-SCL KERALA LIMITED Abdul Haseeb NC, Alex P Jacob, Arvind Kumar, Dibin Vincent UNDERWATER SEARCH AND RESCUE DEVICE Amjith K, Arundas V H, Harikrishnan M, Jeevan Sebastian CAPILLARY WATER PROVISION SYSTEM FOR IRRIGATION Philip Jacob Perakathu, Joju Thomas K, Kiran Thomas, Dheeraj M, Christin Thomas ANALYSIS OF EVAPORATIVE COOLER AND TUBE IN TUBE HEAT EXCHANGER IN INTERCOOLING OF GAS TURBINE Bibin Varkey, G Rahul Krishna, Akhil George Kurian, Adharsh S, Aswin Zachariah

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CFD ANALYSIS OF A 24 HOUR OPERATING SOLAR REFRIGERATION ABSORPTION TECHNOLOGY Arunkumar. H, Benson P Sunny, Arun George, Jesbin Antony EXPERIMENTAL INVESTIGATION OF PERFORMANCE AND EMISSION CHARACTERISTICS OF HYBRID FUEL ENGINE Nirmal Chandran, Blessen Sam Edison, Christy Binu, Godwin Geo Sabu, Jobin K Abey SIX STROKE ENGINE Aarush Joseph Sony, Carol Abraham, Boney Mammen Ajith P Kurian, Prof. Sajan Thomas A STUDY ON THE MECHANICAL PROPERTIES OF NATURAL FIBRE HYBRID COMPOSITE MATERIALS P.Sivasubramanian, Dr.M.Thiruchitrambalam FLUE GAS LOW TEMPERATURE HEAT RECOVERY SYSTEM FOR AIR-CONDITIONING Nirmal Sajan , Ruben Philip , Vinayak Suresh , Vishnu M , Vinay Mathew John SEMI AUTOMATED COCONUT TREE CLIMBER Rahul V, Sameer Moideen CP, Sebin Babu, Vineeth VP, Nikhil Ninan HIGH ALTITUDE AIR FLOW REGULATION FOR AUTOMOBILES Arun K Varghese, Saran S, Shaiju Joseph, Sherin George, Sreelal M MULTISTAGE EPICYCLIC LUG WRENCH Nevin G Ninan, Nithin George, Salu Zachariah, Shinu Baby, Aju Zachariah Mani REGENERATIVE SHOCK ABSORBER Tobin Thomas, Nidhin Abraham Mammen, Sethu Prakash S, Steve John, Varughese Punnoose Kochuparackal AN ASSESSMENT ON DESIGN PARAMETERS AND VIBRATION CHARACTERISTICS OF BOILER FEED PUMP FOR AUXILIARY POWER CONSUMPTION Nikhil Abraham , Sachin Chacko , Sethu Sathyan , Sreenath K G , Parvathy Venugopal LEVER DRIVEN BICYCLE Mebin Mathew, Natheem Nasar, Rahul Mohan M, Vijaya Krishnan R, Er. K C Joseph

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SEMI-ACTIVE SUSPENSION FOR TWO WHEELERS Sanoop Soman, Sherry Shaji, Vipin T Thomas, Vishnu E.M, Arun K Varghese DESIGN AND FABRICATION OF HAND PUMP OPERATED WATER PURIFICATION SYSTEM USING REVERSE OSMOSIS Nikhil Jacob Zachariah, Vimal P Sunil, SachinTomy, Vijith K AN EXPERIMENTAL ANALYSIS ON SYNERGETIC EFFECT OF MULTIPLE NANOPARTICLE BLENDED DIESEL FUEL ON CI ENGINE Sajunulal Franc, Roshith Oommen George, Sachin Jacob James, Mathew John MODELING AND ANALYSIS OF NONPNEUMATIC TYRES WITH HEXAGONAL HONEYCOMB SPOKES Vinay T V, Kuriakose J Marattukalam, Sachu Zachariah Varghese, Shibin Samuel, Sooraj Sreekumar POWERLESS AIR CONDITIONING WITH INTEGRATED WATER HEATING Nishin Asharaf , Nicku Abhraham , Sajin Chacko , Shijo George , Tom Mathew DESIGN AND ANALYSIS OF 3D BLADES FOR WELLS TURBINE Shyjjo Johnson,, Srriirram S Kumarr,, Tom B Thachuparrambiill,, Viivek Joseph John ,, G.Anil Kumar DESIGN AND ANALYSIS OF HEAT EXCHANGER FOR AUTOMOTIVE EXHAUST BASED THERMOELECTRIC GENERATOR [TEG] Rakesh Rajeev, Richu Lonappan Jose, Rohan Mathai Chandy, Thomas Lukose, Er.Nandu S SOLAR DISTILLATION Ken Toms Pothen,NevinSaju Varghese, Nidhish Thomas Jacob, Sachin Mathew, Nikhil Ninan

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Abstract: Loop heat pipes (LHPs) are two phase heat transfer devices that use evaporation and condensation of a working fluid to transfer the heat and use the capillary force developed in fine porous wick to circulate the fluid. They possess all the main advantages of conventional heat pipes, but owing to the original design and special properties of the capillary structure are capable of transferring heat efficiency for distances up to several meters at any orientation in the gravity field, or to several tens of meters in a horizontal position. They do not require any electrical energy for heat transport because of the absence of any mechanical moving parts. The main objective of this project is to fabricate a 2m long loop heat pipe for efficient transfer of heat. The main parts include a wick, a heater block, an accumulator, 2m long copper wire and a condenser. An external fan was introduced to speed up the natural condensation process. The wick was made with copper with 0.3 mm micro drilled pores. The working fluid used is ethanol. After fabricating the model, the pipe was completely filled with ethanol and temperature readings were noted using a temperature sensor at two different positions. A good agreement was reached between the two values.

I.INTRODUCTION Loop heat pipes (LHPs) are two-phase heat transfer

devices. It uses the evaporation and condensation of a working fluid to transfer the heat from one point to other. Capillary forces are developed in the fine porous wicks which helps to circulate the fluid. It does not require electrical power because they have no moving mechanical parts. The pressure loss at the wick in the Loop Heat Pipes can be kept lower than in the conventional HPs. The wick is made of copper instead of PTFE (polytetrafluoroethylene) and has pores of size 0.3mm. Loop Heat Pipes are similar to heat pipes but have the advantage of being able to provide reliable operation over long distance. They can transport a large heat load over a long distance with a small temperature difference. Different designs of Loop Heat Pipes ranging from powerful, large size LHPs to miniature LHPs (micro loop heat pipe) have also been developed and successfully employed in a wide sphere of applications both ground based as well as space applications. Compared with conventional Heat Pipes (HPs), which also use capillary forces to circulate the working fluid, the LHPs can transport heat over longer distances.

In the conventional Heat pipes, vapor flows through the center of the pipe from an evaporation area to a condensation area, while liquid flows through the wick, which is located in the inner surface of the entire pipe, from the condensation area back to the evaporation area. Therefore, if the distance needed for heat transport becomes longer, the length of the wick and the entire pipe also become longer. In contrast, in the LHPs, the wick is located only in the evaporator. Therefore, if the distance needed for the heat transport becomes longer, the length of the wick does not change. Because of this difference, the pressure loss at the wick in the

LHPs can be kept lower than in the conventional HPs. The wicks in the LHPs develop high capillary pressures that are used to operate against gravity and can also be used to increase the horizontal distance for heat transport. The heat losses from vapor and liquid lines to ambient air and due to the pressure losses in the single-and two-phase fluids in the vapor and liquid lines. Figure 1 shows the layout of loop heat pipe.

Unlike conventional heat pipes, the wick structure used in the LHPs should not have excessively high effective thermal conductivity to avoid heat leaks to the liquid present in the compensation chamber. It should be noted that there is a need for compromise between back conduction problem and the desire for good thermal conductivity of wick to promote efficient heat exchange in the evaporating zone

II. COMPONENTSA Copper Tube:

Fig. 2: Copper Tube

Copper tube is most often used for supply of hot and cold tap water, and as refrigerant line in HVAC systems. There are two basic types of copper tubing, soft copper and rigid copper. Copper tubing is joined using LPG welding. Copper offers a high level of corrosion resistance, but is becoming very costly. The vapor line consist of copper tube

Loop Heat PipeGithin V Sam, Jesvin Sam, Jethin Babu, Jithin Victor

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of 0.7in diameter and the liquid line consist of copper tube having 0.5in diameter.

B Fan:

A mechanical fan is a machine used to create flow within a fluid, typically a gas such as air. The fan consists of a rotating arrangement of vanes or blades which act on the fluid. The rotating assembly of blades and hub is known as an impeller, a rotor, or a runner. Usually, it is contained within some form of housing or case. This may direct the airflow or increase safety by preventing objects from contacting the fan blades. Most fans are powered by electric motors, but other sources of power may be used, including hydraulic motors and internal combustion engines. Fans produce flows with high volume and low pressure (although higher than ambient pressure), as opposed to compressors which produce high pressures at a comparatively low volume. A fan blade will often rotate when exposed to a fluid stream, and devices that take advantage of this, such as anemometers and wind turbines, often have designs similar to that of a fan.

C Condenser:

Fig. 3: Condenser

In systems involving heat transfer, a condenser is a device or unit used to condense a substance from its gaseous to its liquid state, typically by cooling it. In so doing, the latent heat is given up by the substance, and will transfer to the condenser coolant. Condensers are typically heat exchangers which have various designs and come in many sizes ranging from rather small (hand- held) to very large industrial-scale units used in plant processes. For example, a refrigerator uses a condenser to get rid of heat extracted from the interior of the unit to the outside air. Condensers are used in air conditioning, industrial chemical processes such as distillation, steam power plants and other heat-exchange systems. Use of cooling water or surrounding air as the coolant is common in many condensers.Natural convection air cooled condenser of dimension 9x9 fin type is used. The fins are made of Aluminium.

D Accumulator:

An accumulator is an apparatus by means of which energy can be stored. A GI moulded accumulator is used to store the working fluid which is ethanol.

E Heater:

Heaters are appliances whose purpose is to generate heat. Such a system contains a boiler, furnace, or heat pump to heat water, steam, or air. The heat can be transferred by convection, conduction, or radiation. Heaters exist for various types of fuel, including solid fuels, liquids, and gases. Another type of heat source is electricity, typically heating ribbons made of high resistance wire. This principle is also used for baseboard heaters and portable heaters. In loop heat pipes,GI ceramic injection moulded heater is used to heat the ethanol.

Fig. 4: Heater

F. Wick:

Fig. 5: Wick

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0.5in diameter copper tube with 0.3mm holes drilled onto the tube acts as the wick. The capillary forces developed in these pores give the required pressure difference to cause the ethanol flow.

G. Ethanol:

Commonly referred to as the drinking alcohol or spirit. It is the principal type of alcohol found in alcoholic beverages.

III. METHODLOGY

Prior to fabrication, model was first designed in CATIA and analysed in ANSYS FLUENT (figure 6) to find out the thermal efficiency. After obtaining the appropriate design, the required materials were purchased and fabrication initiated.

Fig. 6: Analysis of Wick

The wick was initially fabricated by micro drilling 0.3mm holes into the copper tube. The wick is shown in figure 5. One end of the pipe was closed by Gas welding. The wick of diameter 0.6inch was inserted into copper tube of diameter 0.7 inch and Gas welded

Fig. 7: Micro Drilling

The open end of the wick was welded to the accumulator. The accumulator is made of Galvanized iron. The other end of the wick was welded to 2m copper tube which formed the vapor line. The open end of the wick was welded to the accumulator. The accumulator is made of Galvanized iron. The other end of the wick was welded to 2m copper tube which formed the vapor line. At the end of the vapor line, 9*9 inch condenser with aluminum fins was kept.

Fig. 8 Filling Heat Pipe with Ethanol

This causes phase change of the vapour ethanol to liquid. From the condenser to the accumulator, a copper tube of 0.5 inch diameter acts as the liquid line. An injection moulded heater was attached to the accumulator. The entire model was build up on cast iron frame. After assembling the entire model, leak test was conducted by using R-22 and soap solution. After conducting leak test, it was filled with ethanol as shown in figure 8 and sealed. After filling with ethanol, the entire pipe sections were insulated using thermo wool and thermo foam in order to prevent heat from escaping from the tube. The finished model is shown below.

Fig. 9: Fabricated Model

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IV. RESULTS AND DISCUSSIONS

A Temperature Measurement on Two Metre Long Loop Heat Pipe:

After the fabrication process was completed, the process of measuring the temperature at various locations throughout the LHP was carried out. Temperature was measured with the help of two temperature measuring sensors. The first sensor was placed at the starting of vapor line in order to measure the heater temperature. The second sensor was placed at the endof the vapor line.

Fig. 10: Temperature Sensor Readings

It was found that both the temperature readings were approximately close which implies that the capillary structure of the wick material enabled the hot vapor to travel through a distance of 2m through an ordinary copper tube. Two temperature readings are shown in the figure. The heater temperature was 62C and the temperature at the end of the vapor line was 60C.

B.Pressure Losses over Long Distance LHPs:

Fig. 11: Calculated Pressure Loses

Figure 11 shows the calculated distributions of the pressure losses for the LHP. The figure shows that the wick, vapor line, and the liquid line had the largest pressure losses at all

the heat loads. The pressure loss across the liquid line was much larger than those across the wick or the vapor line. To simplify the layout of the LHP, the outside diameters of the liquid line was made smaller as compared to vapor line. This emphasizes that when LHPs are designed for a long distance heat transport, it is important to take into account the pressure loss across the liquid line.

V. CONCLUSIONS

A two metre long Loop Heat Pipe was designed in CATIA and different parts were analysed using ANSYS FLUENT. After analysis we found out that higher efficiency was observed with the new wick design. Unlike the conventional heat pipe which has the wick present throughout the pipe, here the wick is present only at the beginning of the heat pipe. After making the appropriate alterations in the design, the model was fabricated with ethanol as the working fluid.

The capillary forces developed in the fine porous wick helps to circulate the working fluid, thereby eliminating the need for electrical energy as there are no mechanical moving parts. Temperature was measured using two temperature sensors and it was found to be approximately equal at any point in the vapor line. A good agreement was reached between the two values. High efficiency was obtained above 60c..

REFERENCE

[1]Mitomi and Hosei Nagano, Long distance loop heat pipe for effective utilization of energy. International Journal of Heat and Mass Transfer, Vol. 77, pp.777784, (2014). [2]Maydanik, Loop heat pipes.Applied Thermal Engineering, Vol. 25, pp. 635657, (2005). [3]Pastukhov and, Yu.F. Maidanik and C.V. Vershinin and M.A. Korukov, Miniature loop heat pipes for electronics cooling.Applied Thermal Engineering, Vol. 23, pp. 11251135, (2003).

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Abstract: High altitude performance is a major concern for automobiles. Due to lack of air density and pressure at high altitude the mass flow rate to engine drops considerably with altitude. This in turn will affect the volumetric efficiency of the engine. This is an area of great concern for Indian road conditions. The Indian road condition varies from sea level to around 6000m. Thus the engine performance varies drastically will altitude.

We had considered flow through the inlet manifold for a four cylinder turbocharger diesel engine at low and high rpm. At lower rpm at around 1500 the turbocharger boost pressure will negligible, thus the engine will be in natural aspiration. Now at this normal running condition the mass flow to engine drops considerably with altitude. Now for a speed of around 2500 rpm there is sufficient flow to around 3000m and then drops. The flow pattern for a single cylinder in open condition has analyzed to find the average mass flow for different altitude.

I. INTRODUCTION The vortex tube is a mechanical device that separates

single compressed air stream into cold and hot streams. It consists of nozzle, vortex chamber, separating cold plate, hot valve, hot and cold end tube without any moving parts. In the vortex tube, when works, the compressed gaseous fluid expands in the nozzle, then enters vortex tube tangentially with high speed, by means of whirl, the inlet gas splits in low pressure hot and cold temperature streams, one of which, the peripheral gas, has a higher temperature than the initial gas, while the other, the central flow, has a lower temperature. Vortex tube has the following advantages compared to the other commercial refrigeration devices: simple, no moving parts, no electricity or chemicals, small and light weight, low cost, maintenance free, instant cold air, durable, temperature adjustable. Therefore, the vortex tube has application in heating gas, cooling gas, cleaning gas, drying gas, and separating gas mixtures, liquefying natural gas, when compactness, reliability and lower equipment cost are the main factors and the operating efficiency becomes less important.

There are two types of the vortex tube.

(1) Counter flow (2) Uni-flow.

Both of these are currently in use in the industry. The more popular is the counter-flow vortex tube (Figure 1).

The hot air that exits from the far side of the tube is controlled by the cone valve. The cold air exits through an orifice next to the inlet. On the other hand, the uni-flow vortex tube does not have its cold air orifice next to the inlet.

Fig. 1: Counter-flow vortex tube

. This type of vortex tube is used in applications where space and equipment cost are of high importance.

Fig. 2: Uniflow Vortex tube

The mechanism for the uni-flow tube (Figure 2) is similar to the counter-flow tube. A radial temperature separation is still induced inside, but the efficiency of the uni-flow tube is generally less than that of the counter-flow tube. Although the vortex tube effect was known for decades and intensive experiments and correlative investigation had been carried out, the mechanism producing the temperature separation phenomenon as a gas or vapor passes through a vortex tube is not fully understood yet. Several different explanations for the temperature effects in the vortex tube have been offered.

II. RESEARCH METHODOLOGYIn current scenario the air condition system is run by a

part of engine power. In our methodology, we use exhaust power by using a vortex tube for making refrigeration effect. The above figure 3 is the schematic diagram of the proposed project. The engine exhaust is connected to a turbine which is coupled to a compressor. As the turbine rotates, compressor coupled to it rotate and air is drawn from outside .This compressed air is given to the inlet of a vortex tube. In vortex

A NOVEL METHOD FOR SPACE COOLING FROM

AUTOMOBILE ENGINE EXHAUST Jestin James, Jomy Jose, Anoop Vijayan, Boney Thomas Varghese

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tube, the compressed air is entering tangentially through the nozzle near the cold end.

Fig. 3: Schematic of the proposed project The escape of gases through cold end is prevented by a

diaphragm. Thus the air moves towards the hotter side. A throttle body is placed at the hot end to control the cold fraction. A part of air which is rippled back by the throttle body flows back through the core. During this reversed vortex flow energy is given to the outer vortex and thereby getting a cold stream of air at the core. From the values obtained from the journal a suitable vortex tube is modelled using SOLIDWORKS. A six inlet vortex tube is opted for the system.

Fig. 4: Proposed 6 inlet vortex tube model

Figure 6 shows the graph that relates between temperature and L/D ratio. It was based on the experimental data from the journal Experimental study and CFD analysis on Vortex tube by Kalal.M.

It was found that the optimum condition for vortex tube was when the L/D ratio stays between 20 and 55. The temperature separation decreases for L/D ratio above 55 and below 20.

TABLE I DIMENSIONAL DATA FOR VORTEX TUBE

EFFECTIVE LENGTH 300 mm

INLET DIAMETER 2 mm

TOTAL DIAMETER 10 mm

COLD OUTLET DIAMETER 5 mm

NUMBER OF NOZZLES 6

Fig. 5: The model designed in CATIA V5

Fig. 6: Temperature to L/D ratio graph

A. Analysis:

Inlet is given tangentially. Diaphragm prevents the escape of inlet air directly. Six inlets are given to sustain the vortex motion. Properties at the inlet are usually obtained from experimental data, analysis, or estimation. It is very rare that all the boundary conditions required are available from experiment. Quantities of primary importance here are the velocity components normal and tangential to the inlet. In

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axisymmetric flows, the swirl component must also be known. The counter flow vortex-tube type generally has an entrance block with an orifice and a control valve. Compressed gas enters the vortex tube tangentially through one or more nozzles. Most experiments provide inlet data such as pressure, temperature to and mass flow rate just before the nozzle. Unfortunately, they cannot be used as input data for computations which need the data at the nozzle exit stage. Little is known about the static pressure, temperature Tin, and velocity Vn, at the nozzle outlet. Those values may be obtained by extrapolation from their experimental profiles inside the tube to the nozzle exit location. Thus, this practice is adopted for the velocities; the total temperature at the nozzle exit is obtained by assuming an adiabatic nozzle, so that the total energy is conserved throughout the nozzle. Note that the static pressure values inside the flow field are calculated relative to the value at a reference point, for which measurement is available. Density at the inlet is calculated from the continuity equation

1) Meshing:

The partial differential equations that govern fluid flow and heat transfer are not usually amenable to analytical solutions, except for very simple cases. Therefore, in order to analyze fluid flow, flow domains are split into smaller sub domains (made up to geometric primitives like hexahedra and tetrahedra in 3D and quadrilaterals and triangles in 2D). The governing equations are then discretized and solved inside each of these subdomains. Typically one of the methods is used to solve the approximate version of the system of equations: finite volumes, finite elements, or finite differences. Care must be taken to ensure proper continuity of solution across the common interfaces between two subdomains, so that the approximate solutions inside various portions can be put together to give a complete picture of fluid flow in the entire domain. The subdomains are often called elements or cells, and the collection of all elements or cells is called a mesh or grid. The origin of the term mesh (or grid) goes back to early days of CFD when most analysis were 2D in nature. For 2D analyses, a domain split into elements resembles a wire mesh, hence the name.

TABLE II MESHING SPECIFICATIONS OF VORTEX TUBE

SL. NO SPECIFICATIONS

1 NODES 19223

2 ELEMENTS 97609

3 TYPE OF MESHER

TRIANGULAR SURFACE MESHER.

III. RESULT AND DISCUSSIONS

A. Temperature Plot:

Fig. 7: Temperature plot after analysis

Fig. 8: Temperature contour at a plane

The contours of the air stagnation temperature are shown at Figure 8. The area of minimal energy is around the tube axis near the inlet nozzles. The area of maximal gas energy is near the hot outlet ring. The radial differential of the stagnation temperature peaks at the inlet nozzles section. This physical picture is confirmed by the measurements of the stagnation temperature in counter flow vortex tubes. B. Pressure Plot:

According to the results of numerical simulations the following qualitative explanation of the Ranque-Hilsch effect seems to be reasonable. Expanding from inlet nozzle stream of compressed air transforms into highly intensive swirl flow with significant radial pressure gradient (data on pressure distribution are shown at Figure 10). The flow is turbulent, and turbulent eddies can travel in the tube cross-section to the

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center of tube as well as to the peripheral layers. Micro-volumes of fluid traveling from the central core of the vortex to its peripheral area with relatively higher pressure are compressed with corresponding heating. Fluid micro volumes moving to the center of the tube are expanding with cooling. The higher values of initial gas pressure will intensify all the processes responsible for energy exchange and increase the cooling ability of the vortex tube. Numerical analysis results are consistent with original experimental data of R.Hilsch for similar geometry vortex tube.

Fig. 9: Pressure plot for the vortex tube

Fig. 10: Pressure contour for the vortex tube

IV. CONCLUSIONSIn the light of the journals, the modeling of the vortex

tube was conducted and based upon the analysis we reached at the conclusion that the system can be used as an ideal replacement for the conventional air conditioning unit in automobiles. The proposed system adheres to all conventional rules and is more economic than the normal automobile air conditioning unit. Through the proposed system we can reduce the engine load to a certain extend causing the engine to work at a better pace and performance than the normal engine.

From the studies conducted we also plan to conduct a further study regarding the application of our technology in the practical air conditioning and radiator cooling unit.

V. ACKNOWLEDGMENT The authors would like to acknowledge the support of

Mechanical Engineering Department of Saintgits College of Engineering for conducting the present investigation

REFERENCE [1] N.F. Aljuwayhel, G.F. Nellis, S.A. Klein, Parametric and internal study

of the vortex tube using a CFD model, International Journal of Refrigeration, Vol. 28, 2005, pp. 442-450.

[2] P. A. Ramakrishna, M. Ramakrishna, R. Manimaran, Experimental Investigation of Temperature Separation in a Counter-Flow Vortex Tube, Journal of Heat Transfer, Vol. 136, 2014, pp. 082801-1-6.

[3] Kalal M., Matas R, Linhart J., Experimental Study And CFD Analysis On Vortex Tube, International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, HEFAT2008, 2008, pp. KM1 1-8

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PHOTOVOLTAIC DRIVEN THERMOELECTRIC REFRIGERATOR FOR CAR HEAT DISSIPATION DURING SUNNY

DAYS Ashiq Georgi Abraham, Bobby Jacob, Davie George Vinu, Dean John Vinu

Abstract This project outlines the implementation of photovoltaic driven refrigerator in cars powered from solar panels with a battery bank. People normally dont tend to park cars under the sunlight during afternoon time as it causes great discomfort to the person when entering the vehicle after sometime. In order to prevent this thermoelectric module is placed to dissipate the heat that gets built up in the car cabin. This thermoelectric module is powered using nonconventional method, i.e. using solar energy. Hence not using any energy produced by the engine. This method do not cool the cabin but keep it maintained at an optimum temperature.

Different from conventional refrigeration systems, thermoelectric refrigeration, based on the Peltier effect, does not require any compressor, expansion valves, absorbers, condensers or solution pumps. Moreover, it does not require working fluids or any moving parts, which is friendly to the environment and results in an increase in reliability. Thermoelectric refrigeration replaces the three main working parts with: a cold junction, a heat sink and a DC power source. The Peltier effect is a temperature difference created by applying a voltage between two electrodes connected to a sample of semiconductor material. This phenomenon can be useful when it is necessary to transfer heat from one medium to another. Solar energy is the most low cost, competition free, universal source of energy as sunshine's throughout. This energy can be converted into useful electrical energy using photovoltaic technology.

I. INTRODUCTION In the automobile industry, existing air-conditioning

system give arise to numerous problems such as pollution to environment (CFC emission), increase in the usage of fuel and decreased engine performance. Moreover, the current air- conditioning system is not capable to be used during the parked session. The conventional air conditioning system consumes much energy of the engine, when the car parked in sun is cooled. This scenario could be subdued by the introduction of thermoelectric device as an alternating cooling option for car interior. By using this option pollution, fuel usage and decreased engine performance can be prevented since the latter option was in the bracket of Go Green region. Basically, the thermoelectric device known as peltier module is a semiconductor based heat pump, where heat is absorbed from one side and dissipated on the opposite side of the module.

Fig. 1.1 Peltier Module

The peltier module (Fig. 1.1) was discovered by a French watchmaker during the 19th century. It is described as a solid state method of heat transfer generated primarily through the use of dissimilar semiconductor material (P-type and N-type). A typical thermoelectric module is composed of two ceramic substrates that serve as a housing and electrical insulation for P-type and N-type (typically Bismuth Telluride) elements between the substrates. Heat is absorbed at the cold junction by electrons as they pass from a low energy level in the p-type element, to a higher energy level in the n-type element. At the hot junction, energy is expelled to a thermal sink as electrons move from a high energy element to a lower energy element. A module contains several P-N couples that are connected electrically in series and thermally in parallel.

Previously, thermoelectric devices were used in for medical devices, sensor technology, cooling integrated circuits.

The peltier module usually rated according to its capacity on heat removal, waste heat and maximum system temperature difference for a specified DC voltage and applied current. Another important characteristic of peltier module is the polarity of the heat removal changes when the direction of applied current changes, thus it is potential to cool or warm an

9

object within same configuration, with respect to the polarity of the current. When considering usage of these peltier modules, it is necessary to analyze the performance of the module over the heat removal rate. From a manufacturer data sheet of peltier module known as TE Technology, Inc, It is necessary to maintain the system temperature difference with respect to required heat removal in order to maintain the COP performance of the peltier module. Thus, in this project the development of the heat sinks must be considered to fulfill performance requirement. In the context of heat sink resistance, the leading materials that possess high thermal conductivity is copper and aluminum.

When considering peltier cooling with copper or aluminum heat sinks, of course it will cost in high price for the fabrication of the prototype but since this manner of cooling could overcome some disadvantages of existing compressor- based cooling, it is still worth of the price.

1.1 COMPONENTS AND DISCRIPTON When the car is parked during sunny days, the car cabinet

get heated up. The thermoelectric module is powered using a solar panel. The battery is recharged by solar panels and the power is consumed by thermoelectric module from the battery. The temperature sensor is provided in the cabinet to measure the temperature inside the cabinet. A relay circuit is provided along with a microcontroller to cut off the supply from battery to thermoelectric module as the temperature goes below a certain value in the cabinet, thus maintaining a definite temperature.

The major components are, 1. Battery

2. Temperature sensor3. Microcontroller unit4. Solar panel5. Thermo electric cooler6. Relay drive

Battery

We use lead acid battery for storing the electrical energy from the solar panel for lighting the street. Where high values of load current are necessary, the lead-acid cell is the type most commonly used. The lead acid cell type is a secondary cell or storage cell, which can be recharged. The charge and discharge cycle can be repeated many times to restore the output voltage, as long as the cell is in good physical condition. However, heat with excessive charge and discharge currents shortens the useful life to about 3 to 5 years for an automobile battery. Of the different types of secondary cells, the lead-acid type has the highest output voltage, which allows fewer cells for a specified battery voltage.

Advantages

Low cost

Long life High reliability High overall efficiency Low discharge Minimum maintenance

Temperature Sensor Temperature is the most-measured process variable in

industrial automation. Most commonly, a temperature sensor is used to convert temperature value to an electrical value. Temperature Sensors are the key to read temperatures correctly and to control temperature in industrials applications.

A large distinction can be made between temperature sensor types. Sensors differ a lot in properties such as contact- way, temperature range, calibrating method and sensing element. The temperature sensors contain a sensing element enclosed in housings of plastic or metal. With the help of conditioning circuits, the sensor will reflect the change of environmental temperature.

In the temperature functional module we developed, we use the LM34 series of temperature sensors. The LM34 series are precision integrated-circuit temperature sensors, whose output voltage is linearly proportional to the Fahrenheit temperature. The LM34 thus has an advantage over linear temperature sensors calibrated in degrees Kelvin, as the user is not required to subtract a large constant voltage from its output to obtain convenient Fahrenheit scaling.

Microcontroller Unit The alcohol sensor senses the alcohol contents of the

particular room/vehicle. This sensing signal is given to the microcontroller unit. When the current voltage is below the setted voltage, the output from the microcontroller activates the relay to function the alarm unit.

Fig. 1.2 Schematic Layout

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Solar Panel

The most useful way of harnessing solar energy is by directly converting it into electricity by means of solar photo- voltaic cells. Sunshine is incident on Solar cells, in this system of energy Conversion that is direct conversion of solar radiation into electricity.

Thermo Electric Cooler Using a combination of the Seebeck, Thomson and Peltier

effects, cooling occurs when electricity flows through materials and specific junctions. Classic thermoelectric work, but with very low efficiency. The reason is simple. Heat will flow through any material, and does not require electrons to do so. So as soon as one side becomes colder than the other, then natural conduction will seek to equilibrate the two sides.

Thermoelectric coolers (TECs) employ the Peltier effect, acting as small, solid-state heat pumps. The TECs are ideally suited to a wide variety of applications where space limitations and reliability are paramount. The TECs operate on DC current and may be used for heating and cooling by simply reversing the direction of the DC current. Thermoelectric coolers (TECs) are solid-state heat pumps that have no moving parts and do not require the use of harmful chemicals.

Relay Drive A relay is an electro-magnetic switch which is useful if

you want to use a low voltage circuit to switch on and off a light bulb (or anything else) connected to the 220v mains supply.

WORKING PRINCIPLE A Thermoelectric Air cooling for car prototype was

designed and built which can be used for personal cooling inside the car. Six TECs were used for achieving the cooling with a DC power supply through car battery. It had been shown from testing results that the cooling system is capable of cooling the air when recirculating the air inside the car with the help of blower. TEC cooling designed was able to cool an ambient air temperature from 32C to 25.8C. Cooling stabilizes within three minutes once the blower is turned ON. The system can attain a temperature difference of set target which was 7C. Accomplishing the set target establish the success of the project. All the components in the project had been tested individually and the results were found to be positive.

The prototype can be made compact by selecting as single TEC of higher power (.i.e. of 200W or more). It can be done by choosing a better cold side heat sink that has twisted channels or pipes for circulating the air for a longer time. As an alternative for normal axial fan used in this project, if a blower fans is selected, the cooling system would provide better airflow. Even as shown in the appended figure we can mount no of TEC cooling in Roof, Floor, Seat, Door, front dashboard with proper insulation. Well-known TEC brands (.i.e. Melcor, FerroTEC etc) must be chosen if there is only

one high power TEC selected for the cooling system. Bigger hot side heat sinks have to be selected accurately based its calculated thermal resistances for best cooling efficiency. With a single TEC, one hot side and a cold side heat sink a smaller personal TEC cooler which gives comfort can be fabricated and can be installed on roof for individual cooling by changing the airflow and some mechanical or electronics section modification, the TEC air cooling for car can be used for heating applications too.

Advantages Simple in construction Compact and reliable This system is noiseless in operation Its operate in battery Maintenance cost is low

II. MODELLING AND FABRICATIONA solid works model is designed using the above heat load

calculation, The size of windshield=18cm38cm The size of back glass=10cm18cm The area of side glass= 4(10cm15cm)

Fig. 2.1 Front View

Fig. 2.2 Side View

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Fig. 2.3 Top View

Fig. 2.4 Isometric View

2.1 FABRICATION Based on design model the outer frame was designed using

an angle bar. Then a sheet metal of 20 gauge was used to cover the frame made from mild steel. To make the structure arc welding was used. A glass of 4mm thickness with the dimension windshield=18cm38cm, back glass=10cm18cm, side glass= 4(10cm15cm) was incorporated. Then for insulation, the inside of the cabin was covered with 12mm thick thermocole. A 60 Watts Peltier module was placed on the lower part of the cabin such that the hot side lies outside the cabin and the cold side lies inside it. Heat sinks with fan are attached to both hot side and cold side.

Fig. 2.5 Main Frame

Fig. 2.6 Body With Glass Windows

Fig. 2.7 Temperature Sensor and Relay

Fig. 2.8 Peltier Module (Cold Side)

Fig. 2.9 Solar Panels

Fig. 2.10 Peltier Module (Hot Side)

Fig. 2.11 Fabricated Model

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III. EXPERIMENTS AND RESULTS

EXPERIMENTS The scale down model of cabin was placed under direct sunlight with absence of refrigeration system and measured the amount of heat accumulated between 12:00 pm to 1:00 pm for each 15 minutes in the cabin using temperature sensor.

Then the thermoelectric module was switched on and the relay circuit temperature was set to 28C. Then using temperature sensor, reading for each 15 minutes was taken between 2:00 pm to 3:00 pm in order to obtain the rate of cooling.

Then the temperature change with respect to time was plotted.

RESULTS

From the first experiment conducted without using refrigeration system it can be seen that the temperature inside the cabin begins to rise slowly with time since the entire volume of air inside the cabin gets heated up. After a certain period of time the temperature increases rapidly because of the accumulation of heat due to the thermal insulation of the cabin. Towards the end of the experiment the rate of increase in temperature becomes fairly constant. The graph was plotted for the temperature variation for 15 minutes intervals as shown in Fig. 3.1.

50

48

46

44

42

40

38

36

12:00pm 12:15pm 12:30pm 12:45pm 1:00pm

Fig. 3.1 Without Refrigeration System

From the second experiment conducted using the thermoelectric refrigeration system it can be seen that the temperature inside the cabin begins to fall slowly with time since the entire volume of air inside the cabin needs to be cooled. After a certain period of time the rate of cooling slightly increases and as a result the temperature inside the cabin is maintained at ambient condition. The graph was plotted for the temperature variation for 15 minutes intervals as shown in Fig. 3.2.

50 45

40 35 30 25

20 15 10

5 0

2:00pm 2:15pm 2:30pm 2:45pm 3:00pm

Fig. 3.2 With Refrigeration System

IV. CONCLUSIONThe scaled down version of the car cabin was fabricated

from the design calculation. Experiments with and without using the refrigeration system was conducted on the model and the results were compared. Heat load accumulated in the cabin was reduced using this refrigeration method. The temperature inside the cabin was brought down to ambient condition and maintained by means of a relay drive. The thermoelectric system being compact gives a low maintenance cost. The energy used to run the refrigeration system is provided by non-conventional method i.e., using solar energy. As the system contains no moving parts it is reliable and produces no noise.

REFERENCES [1] ASHRAE Handbook of Fundamental, American Society

of Heating, Refrigerating, and Air Conditioning, Atlanta, GA, 1988.

[2] Mohammad A.F., and Majid B., Comprehensive Modeling of Vehicle Air Conditioning Loads Using Heat Balance Method, SAE Technical Paper 2013-01-1507, 2013, doi: 10.4271/2013-01-1507.

[3] Khurmi R.S. and Gupta J.K., Refrigeration and Air conditioning, Eurasia Publishing house Ltd.

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Abstract: Most of the heat energy released from the fuel of an internal combustion engine is wasted to the environment. This is a serious issue in this world of depleting fuels. So an effort is made to recover the heat wasted from the exhaust gas of an internal combustion engine. If the heat wasted out through the exhaust gas is utilized, we can improve the efficiency of the engine to some extent. There are a lot of research works in the field of waste heat recovery systems. Many succeeded in their own methodologies. We hereby attempt to recover the waste heat from the exhaust gas and use the heat energy recovered to improve the efficiency of the internal combustion engine. For the same we studied the exhaust gas temperature of a four stroke diesel engine at various RPM. The exhaust gas temperature at 4000 RPM has got the maximum temperature. So a recovery system for a constant RPM of 4000 is designed. The recovery system consists of a shell and tube heat exchanger and a uniflow steam engine which is coupled to the main engine. The coupled steam engine improves the efficiency of the main engine by lowering the frictional power at the power stroke and idle stroke of the main engine. The initial cost of the system is high due to the additional recovery system. But in the long run the system proves to be profitable

I.INTRODUCTION

In this age of globalization there is a decreasing availability of fossil fuels. So there is a need of conserving it for the future generations. In normal IC engines, a major part of fuel energy is wasted through exhaust gas, cooling water and other losses. We know that a normal IC engine is only 30 to 40 %. This means that the rest of the 70 to 60 % of the heat is lost as waste to the environment. But we know from the basic law of thermodynamics we cannot tap 100% of the available energy. But if we synthesis a method to tap the lost heat from the sink and formulate a method to increase the efficiency of the IC engine, it would be worth for the future generation.

We could tap this lost heat by many ways and utilized it for many purposes. In this project we used a heat exchanger to tap the heat. This heat is further used to increase the efficiency of the engine with the help of a steam. The steam engine cylinder used is considered as an extra cylinder which working together with the other cylinders of the engine whose efficiency is to be increased. The steam engine used gives additional power to the whole system. This additional power decreases the frictional power of the system thereby increasing the efficiency of the IC engine

.

II. METHODOLOGY

The heat energy released to the exhaust gas in engines of various cubic capacities is analyzed.

Engine suitable for this system is selected. The amount of heat in exhaust gas is calculated. Suitable heat exchanger type is selected. Numerical designing of heat exchanger is done. The different parts of the heat exchanger are

modeled using CATIA. The volume of steam chamber required is calculated. The power developed from the steam chamber is

calculated. The software analysis of the heat exchanger and the

steam chamber are done using ANSYS.

III. MAIN WORK PROCEDURE

The main work procedure consists of the following steps: 1) Engine selection.2) Waste heat calculation.3) Selection of heat exchanger.4) Design and analysis of heat exchanger.5) Design and analysis of steam cylinder.6) Calculation of power developed from recovered heat

Fig. 1: Schematic Representation of the System

Exhaust Gas Waste Heat Recovery and Utilization System in IC Engine

Alvin P Koshy, Bijoy K Jose Jeffin Easo Johnson, K Navaneeth Krishnan, Bijeesh P

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A. Engine Selection:

Field analysis and literature study on different engines of various cubic capacity from 150cc to 1500cc were conducted. We studied the temperature of exhaust gas from these engines and found that the temperature is too low for low capacity engines. Temperature is sufficiently high of about 700C in engines of higher capacities. Also, the mass flow rate of the exhaust is higher in large engines. Finally we selected 1573cc diesel engine.

Engine specification:

Engine type : inline 4 cylinder Bore : 75mm Stroke : 89mm Displacement : 1573cc Compression ratio : 18 Rated power : 80bhp@4000rpm

We also checked the exhaust gas temperature from the engine when it is working under various rpm, i.e. from 1000rpm to 4000 rpm. Here we also found that the temperature is high when the engine speed is 4000 rpm.

Table-1: Exhaust Gas Properties at Various Engine Speeds

ITEM CONTENT Engine Speed(rpm) 1000 2000 3000 4000 Engine Power (kW) 14.9 50.2 70.8 84.8

Exhaust temperature(K) 801.5 862.4 890.8 900.5 Exhaust mass flow rate(g/s) 18.7 59.6 83.3 108

B. Heat Content of Exhaust Gas:

We measured the temperature of the exhaust gas from the engine at 4000rpm. We obtained the mass flow rate of exhaust gas at this rpm as 0.108kg/sec. The specific heat capacity of exhaust gas is 1.185kJ/kgK. So heat duty of exhaust gas at 4000rpm is calculated as:

Qmax = ex cpex T = 0.108*1.185*(737-30) = 90.4kW Where, ex = mass flow rate of exhaust gas cp = specific heat T = temperature difference= inlet temperature of

exhaust inlet Temperature of working fluid This is the maximum heat that can be transferred from

exhaust gas to the cooling fluid.

C. Heat Exchanger Selection:

Since we have to run a steam engine which works with the pressure of the steam, it should be critically noted that the heat exchanger selected should be on with minimum pressure drop. Also, the function of our heat exchanger is to transfer the heat from the exhaust gas to the working fluid, and the working fluid has to be vaporized and superheated when coming out from the heat exchanger.

Based on the requirements, we studied the characteristics of the available types of heat exchangers and found out that horizontal shell and tube heat exchanger with counter flow arrangement is the best suited one for our application.

D. Design Considerations:

The working is fed to the heat exchanger at a pressure of 10bar and the heat exchanger designed should provide steam at the outlet of shell with pressure drops within allowable limit. The exhaust gas is fed to the tube at a pressure of 5bar. Designing of the heat exchanger is usually done on the basis of certain assumptions.

There is no heat transfer between the fluid streams and the outside environment. There are no leakages from the fluid streams to each other or to the environment. No heat is generated or lost via chemical or nuclear reactions, mechanical work or other means. There is no heat conduction along the length of the heat transfer surface, only in the direction of the normal of the surface. Fluid flow rates are equally distributed throughout the whole cross-sectional areas of flow. Where temperature distribution transverse to the flow direction is relevant, any fluid flow can be considered either completely mixed or completely unmixed. Properties of fluids are constant inside the heat exchanger. Overall heat transfer coefficient is a constant at all locations of the heat exchanger. Initial assumption that overall heat transfer coefficient U = 150 W/m2. Negligible fouling resistance occur in the heat exchanger

E. Designing Procedure:

The process of sizing a heat exchanger will inevitably be an iterative one. To calculate the area one has to have at least an estimate of U, once an area is calculated on the basis of the estimate (or guess), the geometry of the heat exchanger will be known so that a better estimate of U can be calculated, leading to a better estimate of the area, therefore some change in geometry, requiring a new value of U to be calculated, and so on.

Processes taking place in heat exchanger: Heating working fluid from 30 to 179.9

15

Vaporization of the working fluid at 179.9 Superheating of the working fluid to 205 .

Since these stages occur

Calculation of mass flow rate of working fluid:

We know the maximum heat transferred from the working fluid. We also know the processes happening to the working fluid. So the flow rate of working fluid can be calculated by the following steps.

To increase temp of WF

Q1 = wf cpwf T= wf 4.18 (179.9 30)= 626.528 wf

To vaporize

Q2 = wf hfg= 2013.6 wf

To superheat

Q3 = wf cpwf T

= wf 2.085(205-179.9)= 52.335 wf

Qmax = Q1 + Q2 + Q3 90.481= wf (626.582+2013.6+52.335)

= wf 2692.5155

wf = 0.03360kg/sec

1) - NTU Method:

The -NTU method of heat exchanger analysis is based on three dimensionless parameters: the heat exchanger effectiveness , ratio of heat capacity rates of the fluid streams CR, and number of transfer units NTU. is a function of heat duty and/or outlet temperatures and NTU a function of heat transfer area. Functions correlating the three dimensionless parameters to each other exist for a variety of flow arrangements. Use of the -NTU method starts by solving two of the dimensionless parameters from what is known about the situation, and then using the correct -NTU relationship to find the third. From that value and defin of the third dimensionless parameter one then solves what needs to be

determined: for example the required heat transfer area from NTU in a sizing problem, or fluid outlet temperatures from in a rating problem.

Find out the mass flow rate of working Finding out the temperature of exhaust gas after each

phase Finding out the value of heat capacity ratio R; Based on the value of R from standard graph

between - NTU, take values of NTU for maximumeffectiveness.

Take estimated value of U for shell and tube heatexchanger for doing initial iteration

Calculate the area required Fix standard tube and shell diameters Find out the number of tubes required Fix the number of tubes as specified by s standards Assume single pass and find out the velocity and

Reynolds number for exhaust flow

Table-2: Heat Exchanger Design Specifications

IV. MODELLING OF HEAT EXCHANGER

Parts of the heat exchanger is designed and made using CATIA. The major parts of heat exchanger are:

Tube Shell Front end head Rear end head Tube Plate

PROPERTY VALUE Effectiveness 76.3

Total heat exchange area 18.27m2 Tube pitch 1 inch square pitch

Tube inner diameter 12.2mm Tube outer diameter 19.1mm Shell inner diameter 438.15mm

No of tubes 150 No of passes 6 No of baffles 11

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Fig. 2: Front End Head

Fig. 3: Rear End Head

Fig. 4: Shell

Fig. 5: Tube Plate

Fig. 6: Tube

Fig. 7: Tubes Assembled in Tube Plate

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Fig. 8 Fully Assembled Heat Exchanger

V. ANALYSIS OF HEAT EXCHANGER COMPONENTS

Fig. 9: Stress Distribution in Front End Head

Fig. 10: Deformation in shell

Fig. 11: Strain in Font End Head

Fig. 12: Stress Distribution in Shell

Fig. 13: Stress Distribution in Tube

From the above analysis done in ANSYS R15.0, we could understand that the maximum stress on the parts is much lesser than the yield strength of the material made. Hence the design is safe.

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From the above analysis we could clearly understand that the design safe with a very high factor of safety.

VI THEORETICAL ANALYSIS OF THE STEAM ENGINE

A Steam Engine Cylinder Design Assumptions:.

The cylinder is one of the main parts of the steam engine. The design of steam engine requires certain assumptions. The main assumption is that the working fluid cut off percentage. Another assumption is that the stroke length is fixed to obtain a particular bore for the steam engine. This is to provide the steam engine with the stroke length as that of the IC engine stroke length. So a stroke length of 0.0889 m is assumed for the steam engine. The cut off of the working fluid is at 50% of the cylinder volume. Thus with these assumptions we could determine the volume of the steam chamber required

B Volume of the Steam Chamber

Volume flow rate of working fluid = volume flow rate of steam chamber cut off Mass flow rate, m = 0.0313 kg/sec Density of steam, = 4.529 kg/m

3

Hence the required volume of the steam engine cylinder is 213cm3.

C. Cam Design: The cam profile is designed such that the cut off of the working fluid is at 50%. The lift of the valve is 4.5mm which is 45 deg.

Fig. 14: Cam Follower Displacement Diagram

Fig. 15: Cam Profile

This is the required cam profile that is used to produce the required displacement of the valve.

D Theoretical Analysis of Steam Engine:

The analysis is carried out on the assumption that the steam engine is having an efficiency of 15%. The assumption is on the basis that normal steam engine efficiency ranges from 10 to 20%. IC engine is operating0 at 4000 RPM and at full load. The gross power output from the steam chamber is calculated as follows.

Recovered heat = 68.15 kW Power output = 68.15*0.15

= 10.2225 kW Power loss due to pump = vp = 7.09410-3 9105 kW = 6.3846 kW This is the power loss from pump. The gross power = 10.2225-6.3846 = 3.8379 kW

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E. Strokes in Engine Cylinders:

Table-2: Strokes in Engine Cylinders

CYLINDER NUMBER STROKES 1 S C P E 2 E S C P 3 P E S C 4 C P E S

5 (Steam cylinder) E P E P

Where, S = suction stroke C = compression stroke P = power stroke E = exhaust stroke

F. Improvement in Engine Performance:

1) Variation in Thermal Efficiency:

Thermal efficiency, of the IC engine = 37.3%

We also know brake power = 80 KW (Mass of fuel/sec) Calorific value of diesel = 214.477 kW New brake power = bp of IC engine + (bp of steam engine)/2 = 80+1.91895 = 81.91895 kW Increase in thermal efficiency = 0.8947%

2) Variation in Brake Specific Fuel Consumption:

Brake specific fuel consumption, bsfc of the IC engine = 225 g/kWhr

Fuel consumption for unit time for 80 KW = 18000 g/hr The new bsfc = 219.72 g/kWhr

There is a decrease in bsfc = 5.28 g/kWhr

VII. CONCLUSIONS

This is a novel mechanism which improves the performance of the engine. The power of the engine increases from 80 kW at 4000 RPM to 81.91895 kW. The thermal efficiency increases from 37.3% to 38.19%.There is a decrease in the bsfc by 5.28 g/kWhr. The initial cost of the recovery mechanism is very high. But this becomes economic in long run. The analysis is carried out theoreticallybut there may be differences when it is experimentally analyzed. The low value of the recovered heat is due to the small engine that we took. The improvement in the performance of the engine is due to the fact that the power developed by the mechanism is utilized to decrease part of the frictional power of the engine.

VIII. FUTURE SCOPE

The recovery mechanism should be experimentally analysed. An organic working fluid may be used in place of water. The experiment may be conducted in big engines which may be more effective than small engines. The experiment may be conducted at various RPM and loads. A recovery mechanism should be developed for engines working at various RPM and loads.

ACKNOWLEDGEMENT

The authors would like to acknowledge the support of Mechanical Engineering Department of Saintgits College of Engineering for conducting the present investigation

REFERENCE 1] Jianqin Fu, Jingping Liu, Yanping Yang, ChengqinRen, Guohui Zhu- A new approach or exhaust energy recovery of internal combustion engine , Applied Energy, 2013, pp.150-159.

[2] J.S. Jadhao, D.G. Thombare- Review ofn exhaust gas recovery for I>. engine, Applied Energy, 2013 .

[3] Kiran K. KattaMyoungjin Kim- Exhaust heat co generation using phase change for heavy duty vehichles Applied Energy, 2007.

[4] Q.A Kern Process heat transfer

[5] C P Kothandaraman, S Subramanyan Heat and mass transfer data book

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Abstract: Extended surfaces commonly known as fins, offer an economical and trouble free solutions in many situations demanding natural convection heat transfer. Heat sinks in the form of fin arrays horizontal and vertical surfaces used in variety of engineering applications, studies of heat transfer and fluid flow associated with such arrays are of considerable engineering significance. The main controlling variable generally available to designer is geometry of fin arrays. Considering the above fact natural convection heat transfer from triangular fin arrays have been investigated experimentally and theoretically. Fin optimization is useful to go through the exercise of optimizing a fin in order to achieve the high rate of heat transfer per volume of fin material. The result of this optimization provides general guidelines relative to the dimensionless characteristics of a well- designed fin.

I. INTRODUCTION

Fins are extended surfaces often used to enhance the rate of heat transfer from the engine surface. Fins are generally used on the surface which has very low heat transfer coefficient. Straight fins are one of the most common choices for enhancing better heat transfer from the flat surfaces. The rate of heat flow per unit surface area is directly proportional to the added heat conducting surface. The major heat transfer takes place in two modes i. e. by conduction or by convection. Heat transfer through fin to the surface of the fin takes place through conduction whereas from surface of the fin to the surroundings takes place by convection. Further heat transfer may be by natural convection or by forced convection.

Due to the high demand for lightweight, compact, and economical fins, the optimization of the fin size is of great importance. The removal of excessive heat from system components is essential to avoid the damaging effects of burning or overheating. Therefore, the enhancement of heat transfer is an important subject in thermal engineering. The study of convective heat transfer originates from humans desire to understand and predict the amount of energy which is observed through any fluid flow as an energy transferring mediums. The science of convection is an interdisciplinary field which connects two earlier sciences, Heat Transfer and Fluid Mechanics.

The rectangular fin is widely used, probably, due to simplicity of its design and its less difficult in manufacturing process. However, it is well-known fact that the rate of heat transfer from a fin base diminishes along its length. The optimum profile has been determined which may be circular or parabolic depending upon the consideration of with or without the idealization of length of arc. On the other hand, a triangular fin is attractive, since, for an equal heat transfer, it requires much less volume (fin material) than a rectangular profile. Nevertheless, since heat transfer rate per unit volume

for a parabolic profile is only slightly greater than that for the triangular profile, its use can scarcely be justified in view of its larger manufacturing costs.

II. RESEARCH METHODOLOGYModel is a Representation of an object, a system, or an idea in some form other than that of the entity itself. Modeling is the process of producing a model; a model is a representation of the construction and working of some system of interest. A model is similar to but simpler than the system it represents. One purpose of a model is to enable the analyst to predict the effect of changes to the system. On the one hand, a model should be a close approximation to the real system and incorporate most of its salient features. On the other hand, it should not be so complex that it is impossible to understand and experiment with it.

Fig. 1: Isometric View of Single Fin

Figure 1 shows the isometric view of a Single Fin. A good model is a judicious tradeoff between realism and simplicity. Simulation practitioners recommend increasing the complexity of a model iteratively. An important issue in modeling is model validity.

Model validation techniques include simulating the model under known input conditions and comparing model output with system output. Generally, a model intended for a simulation study is a mathematical model developed with the help of simulation software.

Fig. 2: Array of Fins Showing the Pitch Selected

STUDY, DESIGN AND OPTIMIZATION OF TRIANGULAR FINS Abel Jacob, Gokul Chandrashekhara, Jerin George, Jubin George

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A. Meshing:

Fig. 3: Mesh of Array with l/d ratio = 1

The figure 3 shows the updated mesh obtained for the array of triangular fins with l/d ratio = 1. In order to increase the accuracy of the convergence graph, the relevance centre was chosen of fine type instead of coarse type. The total number of nodes and elements are shown in Table 1 below.

Fig. 4: Mesh of Array with l/d ratio = 1.5

The figure 4 shows the updated mesh obtained for the array of triangular fins with l/d ratio = 1.5. In order to increase the accuracy of the convergence graph, the relevance centre was chosen of fine type instead of coarse type. The total number of nodes and elements are shown in Table 7.1 below.

Fig. 5: Mesh of Array with l/d ratio = 2

The figure 5 shows the updated mesh obtained for the array of triangular fins with l/d ratio = 2. In order to increase the accuracy of the convergence graph, the relevance centre was chosen of fine type instead of coarse type. The total number of nodes and elements are shown in Table 1 below.

III. RESULT AND DISCUSSIONSAfter the generation of mesh and assigning of load and

constraints next step is to run the simulation for the model. This proceeds for the analyzing the steady-state heat transfer process and finally obtain the required result contour of temperature.

Fig. 6 temperature contour for single fin with l/d ratio = 1

The resultant figure 6 shows the variations of temperature along length of fin with triangular extensions. It can be interpreted that the maximum value of temperature is found to be at 6.980102 K; while the minimum value of temperature is found to be at 3.00102 K. The source temperature from engine block was assumed to be 690K and the air temperature was taken as 300k.

L/D RATIO NUMBER OF NODES

NUMBER OF ELEMENTS

1 35151 179456

1.5 35992 183262

2 36403 184240

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The resultant figure 8.2 shows the variations of pressure along length of fin with triangular extensions. It can be interpreted that the maximum value of pressure is found to be at -1.466101 Pa.; while the minimum value of pressure is found to be at 9.902101 Pa.

Fig. 7: Pressure Contour for Single Fin with L/D Ratio = 1

Fig. 8: Temperature Contour for Single Fin with L/D Ratio = 1.5

Fig. 9: Pressure Contour for Single Fin with L/D Ratio = 1.5

The resultant figure 9 shows the variations of pressure along length of fin with triangular extensions. It can be interpreted that the maximum value of pressure is found to be at -1.466101; while the minimum value of pressure is found to be at 9.902101 Pa.

Now we take single fin of L/D ratio = 2 (i.e. ratio of length of fin to width of fin is 1.5). We analyze the pressure and temperature contour formation of the fin when the source temperature is set as 690k and atmospheric pressure is taken as 1 Pa. Then we find the heat transfer rate from the fin.

Fig. 10: Temperature Contour for Single Fin with L/D Ratio = 2

The resultant figure 10 shows the variations of pressure along length of fin with triangular extensions. It can be interpreted that the maximum value of pressure is found to be at -1.466101 Pa; while the minimum value of pressure is found to be at - 9.902101 Pa.

Fig. 11: Pressure Contour for Single Fin with L/D Ratio = 2

The resultant figure 11 shows the variations of pressure along length of fin with triangular extensions. It can be interpreted that the maximum value of pressure is found to be at -1.466101 Pa; while the minimum value of pressure is found to be at - 9.902101 Pa.

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The resultant figure 12 shows the variations of pressure along length of array of fins with triangular extensions. It can be interpreted that the maximum value of pressure is found to be at -1.466101 Pa and the minimum pressure is found to be at - 9.902101 Pa.

Fig. 12: Temperature Contour for an Array of Fins with Pitch 50and L/D Ratio = 1.5

Now we analyze the heat transfer rate of an array of fins with pitch 50mm (i.e., distance between two corresponding points on adjacent fins is 50mm) and L/d ratio = 1.5 (i.e. ratio of length of fin to width of fin is 1.5). We analyze the pressure and temperature contour formation of these fins when the source temperature is set as 690k and atmospheric pressure is taken as 1Pa.

Fig. 13: Pressure Contour for an Array of Fins with Pitch 50 and L/D Ratio = 1.5

The resultant figure 13 shows the variations of pressure along length of array of fins with triangular extensions. It can be interpreted that the maximum value of pressure is found to be at -1.466101 Pa and the minimum pressure is found to be at - 9.902101 Pa.

The resultant figure 14 shows the variations of temperature along an array of fins with triangular extensions.

It can be interpreted that the maximum value of temperature is found to be at 6.980102 K; while the minimum value of temperature is found to be at 3.00102 K. The source temperature from engine block was assumed to be 690K and the air temperature which was taken as the input to measure convective heat transfer wsas given a value on 300 K.

Fig. 14: Temperature contour for an array of fins with pitch 50and l/d ratio = 2

Fig. 15: Pressure Contour for an Array of Fins with Pitch 50 and L/D Ratio = 2

The resultant figure 15 shows the variations of pressure along length of array of fins with triangular extensions. It can be interpreted that the maximum and minimum value of pressure is found to be at 1.000105 Pa.

Fig. 16: Residual graph for Single Fin with L/D Ratio = 1

The resultant figure 16 shows residual graph of convergence of temperature and pressure and values of

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continuity equation for single fin with L/D ratio = 1. The values converges after 1000 iterations to a value close to

Fig. 17: Residual graph for Single Fin with L/D Ratio = 1.5

The resultant figure 8.12 shows residual graph of convergence of temperature and pressure and values of continuity equation for single fin with L/D ratio = 1.5. The values converges after 1000 iterations to a value close to

Fig. 18: Residual graph for Single Fin with L/D Ratio = 2

The resultant figure 18 shows residual graph of convergence of temperature and pressure and values of continuity equation for single fin with L/D ratio = 2. The values converges after 1000 iterations to a value close to The resultant figure 19 shows the variations of temperature along an array of fins with rectangular extensions. It can be interpreted that the maximum value of temperature is found to be at 6.980102 K; while the minimum value of temperature is found to be at 2.98102 K.

The source temperature from engine block was assumed to be 690K and the air temperature which was taken as the input to measure convective heat transfer was given a value on 300 K.

Fig. 19: Temperature contour for an array of rectangular fins with pitch 50and l/d ratio = 2

Fig. 20: Pressure contour for an array of rectangular fins with pitch 50and l/d ratio = 2

The resultant figure 20 shows the variations of pressure along length of fin with rectangular extensions. It can be interpreted that the maximum value of pressure is found to be at 3.83710-2 Pa; while the minimum value of pressure is found to be at - 1.365100 Pa

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IV. CONCLUSIONSFrom the result it is clear that as the l/d ratio increases,

the heat transfer also increases up to a certain limit. It is clear that as the pitch of the fins increases the heat transfer to a maximum value and then decreases. In comparison to the conventional fin (rectangular), rate of heat transfer of proposed fin is increased by 28.7%.Triangular fins provide about 5 % to 13% more enhancement of heat transfer as compared to conventional fins. Heat transfer through fin with triangular extensions higher than that of fin with other types of extensions. The effectiveness of fin with triangular extensions is greater than other extensions.

V. ACKNOWLEDGMENT

The authors would like to acknowledge the support of Mechanical Engineering Department of Saintgits College of Engineering for conducting the present investigation.

REFERENCE [1] Tri Lam Ngo et al, Heat transfer and pressure drop correlations of

micro channel heat exchangers with S-shaped and zigzag fins for carbon dioxide cycles.

[2] .GiulioLorenzini et al, Constructed design of TY assembly of fins for an optimized heat removal.

[3] GiulioLorenzini et al,Numerical analysis on heat removal from Y -shaped fins: Efficiency and volume occupied for a new approach to performance optimization.

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Abstract: A new concept of steam turbocharging is proposed in this project which finds a solution for the major disadvantages of conventional turbocharging systems. In conventional turbocharging system the turbocharger starts operating only after certain engine rpm. The back pressure generated at the engine exhaust is also high in conventional systems. These disadvantages are being solved in this proposed project.

The major objectives of this project are to achieve a target boosting pressure of 1.5 bar at the engine inlet, to reduce the backpressure at the engine exhaust and to increase the operating range of turbocharger. The IC engine exhaust energy is used to generate steam and then drive the turbine. Part of steam expansion power is used to drive air compressor. The heat exchanger and turbine are designed and simulated and the performance is analyzed.

The results show that IC engine power can be increased by increasing the inlet boosting pressure. The analysis shows that in steam turbocharging system, the turbocharger starts working at 1000 rpm and has less exhaust back pressure compared to ordinary turbocharger.

I. INTRODUCTION The power performance and fuel economy of an Internal

Combustion(IC) engine can be increased by boosting the intake pressure. By increasing the intake boosting pressure the BMEP also increases which leads to higher thermal efficiency. By increasing the boosting pressure the engine displacement can also be downsized. Exhaust turbocharging is most widely used method when compared to other boosting pressure technologies. Exhaust turbocharging is a method of Exhaust Energy Recovery (EER) in which the energy of the exhaust gas is used to run a turbine which in turn runs a compressor and boost the intake air to IC engine and thus improves its performance.

In conventional exhaust turbocharging systems used in diesel engines only a part of the exhaust energy can be used efficiently the rest of the exhaust energy is wasted. This is because the exhaust gas contains mainly of thermal energy than pressure energy. In exhaust turbocharging an additional back pressure is also created which leads to less volumetric efficiency of the IC engine and more work during the exhaust stroke. Therefore some of the exhaust energy recovered is used to overcome this pumping loss. At low speeds of IC engine the exhaust energy may be less than the pumping loss, so at lower speeds the target boosting pressure may not be achieved. So exhaust turbocharging is not the best method to recover the exhaust energy or boost the intake pressure. Here we introduce a new concept which utilizes IC engine exhaust thermal energy to boost intake pressure. Since it is based on steam power cycle it is named as Steam Turbocharging, which is more effective when compared to IC engine exhaust turbocharging.

II. RESEARCH METHODOLOGYThe proposed concept of steam turbocharging is based on Rankine steam cycle. As said earlier in steam turbocharging thermal energy of exhaust gas is used instead of pressure energy. The exhaust thermal energy is recovered using heat transfer and this energy is used to generate effective work using a turbine. Finally, the output power of the turbine is used to run a compressor. Figure 1 shows the schematic diagram of steam turbocharging system. As shown in Figure 1, the steam turbocharging system consists of, valve, water tank, pump, heat exchanger, steam turbine, and air compressor, etc. Among these components, valve is used to adjust the mass flow rate of working medium water, while pump is used to control the pressure through the cycle. A motor is coupled to the transmission shaft connecting turbine and compressor to control the energy flow in the cycle. The modes of operation of motor are described as follows. (a) Driving the air compressor: at lower rpm of engine speed, the steam turbine does not work instantly and air compressor is driven by the motor to obtain target boosting pressure; since at low speeds the exhaust energy is less both motor as well as steam turbine is used to run the compressor (b) At higher engine speeds the turbine power generated is greater than required power to run the compressor so this energy is used to generate electricity from the motor. Both the air compressor and motor is run by steam turbine so the extra energy generated by the turbine is converted to electrical energy by motor. The steam turbocharging system shown in Figure 1 is an open steam power cycle system, which can be also designed as a closed system based on its application. In closed system the water used in the cycle is used again and again whereas in open system it is used only during a single cycle. Since there is no condenser and condensation in open cycle system it is comparatively simple. The cost of open cycle system is also less when compared to closed cycle system. Steam turbocharging based on open cycle has its major application in steam power plants. The working medium that is water must be available in plenty. Steam turbocharging based on closed system has wider applications since the working medium is recycled throughout the cycle. It can me both used in stationary as well as mobile applications such as in automobile and marine engines. This paper mainly deals with open cycle system and the working principle of both systems are moreover same.

SSTTEEAAMM TTUURRBBOOCCHHAARRGGIINNGGAbhijith P, Akhilesh Rajan, Cyril Soji Thomas, Kevin George Jacob

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Fig.1.Schematic Diagram of Steam Turbocharging

2.1 MODELLING

2.1.1 DESIGN PROCEDURE OF COMPRESSOR

A compressor is designed to produce 1.5 bar boosting pressure at the engine intake. To achieve that boosting pressure we have designed a compressor using the following formula. The analysis is carried out at the engine speed of 1000 rpm.

Where, m in is the mass flow rate of intake gas; CP is the constant pressure specific heat of intake gas; T1 and T2 are the intake gas temperature at the inlet and outlet of compressor, respectively. P1 and P2 are the intake gas pressure at the inlet and outlet of compressor, respectively; r is the specific heat ratio of intake gas. com is the isentropic efficiency of compressor.

The power required by the compressor is thus calculated from the above equation. By analyzing the results we came to a conclusion that garret 1544 turbocharger compressor will produce the desired pressure boosting.

Table 1 Basic Parameters of Test Engine

ITEM CONTENT ENGINE TYPE INLINE FOUR CYLINDER DISPLACEME

NT (L) 1.573 COMPRESSION RATIO 18

RATED POWER (KW/RPM) 80/4000

Table 2 Theoretically Calculated Compressor Specification ENGINE RPM 1000

MASS FLOW RATE 0.0158757

POWER REQUIRED 0.82(KW)

Fig 2 Compressor Chart of Selected Compressor

Fig.3. Proposed Turbocharger Compressor

Fig 3 is the picture of the turbocharger compressor we selected after the calculations. From the compressor chart in Fig 2 we can see that this compressor meets our requirements.

2.1.2 DESIGN PROCEDURE OF HEAT EXCHANGER

The exhaust gas from the engine is supplied to a heat exchanger in this proposed project. The energy of the exhaust gas is used to convert pressurized water to steam.

The steps involved in designing a heat exchanger are:

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Step 1. The thermal and physical properties of hot and cold fluid is obtained and these properties are calculated at mean temperature. Step 2. From energy balance equation obtain the energy transferred to heat exchanger. Step 3. The value of overall heat transfer coefficient is assumed a approximate value (Uo, assm). The assumed value of Uo can be obtained from heat and mass transfer data book. Step 4. Determine required number of shell and tube passes (p, n). Step 5. Calculate area of heat transfer (A) required. Step 6. Select material of tube, select the tube diameter, its wall thickness and length of tube (L). Also calculate the number of tubes. Step 7. Determine type of shell and tube exchanger. Select the tube pitch (Pt), decide inside shell diameter (Ds) that can accommodate the calculated number of tubes (n). Step 8. Assign fluid to shell or tube side.

In the designed heat exchanger the value of heat transfer coefficient is assumed to be 150 W/m2. The exhaust gas is passed through the tube side and the pressurized water is passed through the shell side.

Table 3 Theoretical Design Values of Heat Exchanger ITEM CONTENT

AREA OF HEAT EXCHANGER 0.2802 NO OF TUBES 30 OUTSIDE DIAMETER OF TUBE 31mm INSIDE DIAMETER OF TUBE 25.4mm NO OF PASSES 2 SHELL DIAMETER 28.62 cm LENGTH OF HEAT EXCHANGER 118cm EXHAUST GAS TEMPERATURE AT 801.1 K 1000 RPM EXHAUST MASS FLOW RATE AT 0.087 kg/s 1000 RPM

Fig.4. Solidworks Model of Designed Heat Exchanger

2.1.3 DESIGN OF REACTION TURBINE FOR POWER GENERATION

The pressurised water which is fed into the heat exchanger is turned to steam by using the exhaust gas energy from engine. The steam at 5 bar pressure from the outlet of heat exchanger is directly fed to a reaction turbine to generate power required to run the compressor. The design of reaction turbine is done using ANSYS Vista RTD software. The geometry of turbine blade is generated using vista RTD and it is developed using BladeGEN of ANSYS. The analysis of the turbine blade is done using ANSYS Fluent 15. The model of the turbine blade developed through Vista RTD is shown in the Figure 5.

Fig.5. Turbine Blade Geometry Figure 5 shows the geometry of turbine blade which is designed using Vista RTD. The envelop over the blade geometry shows the flow path or control volume. The blade is so designed that the steam gets expanded to a pressure of 1 bar at the outlet of the turbine.

III. RESULT AND DISCUSSIONS

The heat exchanger and turbine analysis were done on ANSYS Fluent 15.0. The results are shown below:

Fig 6 Tube side Temperature Distribution The Figure 6 shows the temperature distribution of tube side fluid. The temperature of exhaust gas at tube inlet is around 801K and when it comes out of heat exchanger its

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temperature decreases to 450K. Figure 7 shows the shell side temperature distribution of same heat exchanger. In the shell side water enters at around 303K and leaves at around 423K as steam. The water is supplied to the heat exchanger at a pressure of 5bar using a pump. Figure 8 shows the contours of static pressure in a turbine blade. The steam enters at a pressure of 4.7 bar and expands to around 1 bar pressure. There are a total of 9 blades in the runner desig