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ENGINE TEST SET UP
3 CYLINDR, 4 STROKE, PETROL
Instruction manual
Contents
1 Description
2 Specifications
3 Installation requirements
4 Installation Commissioning
5 Troubleshooting
6 Components used
7 Packing slip
8 Warranty
9 Theory
10 Experiments
APEX INNOVATIONS
Product Code 231
Apex Innovations
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The setup consists of three
cylinder, four stroke, Petrol
engine connected to Eddy
dynamometer for engine
loading. The setup has stand-
alone type independent panel
box consisting of air box, fuel
tank, manometer, fuel
measuring unit, digital speed
indicator and digital
temperature indicator. Engine
jacket cooling water inlet,
outlet and calorimeter
temperature is displayed on
temperature indicator.
Rotameters are provided for
cooling water and calorimeter
flow measurement.
The setup enables study of
engine for brake power, BMEP,
brake thermal efficiency, volumetric efficiency,
specific fuel consumption, air fuel ratio and heat
balance. Set up is supplied with MS Excel
program for Engine Performance Analysis.
Product Engine test setup 3 cylinder,4 stroke, Petrol
Product code 231
Engine Make Maruti, Model Maruti 800, Type 3 Cylinder, 4
Stroke, Petrol (MPFI), water cooled, Power 27.6Kw at
5000 rpm, Torque 59 NM at 2500rpm,stroke 72 mm,
bore 66.5mm, 796 cc,CR 9.2
Dynamometer Type Eddy current, water cooled with loading unit (Arm
length 210 mm)
Propeller shaft With universal joints
Air box M S fabricated with orifice meter and manometer
(Orifice dia 35 mm)
Fuel tank Capacity 15 lit with glass fuel metering column
Calorimeter Type Pipe in pipe
Temperature sensor Thermocouple, Type K
Temperature
indicator
Digital, multi channel with selector switch
Speed indicator Digital with non contact type speed sensor
Load sensor Load cell, type strain gauge, range 0-50 Kg
Load indicator Digital, Range 0-50 Kg, Supply 230VAC
Rotameter Engine cooling100-1000 LPH;Calorimeter 25-250 LPH
Pump Type Monoblock
Overall dimensions W 2000 x D 2750 x H 1750 mm
Shipping details
T3
T2
F1 F2
T1
T5
Wt
N
DYNAMOMETER ENGINE
T4
F3 F4
AirFuel
Specifications
Description
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Gross volume 1.64m3, Gross weight 755kg, Net weight 910kg
Electric supply
Provide 230 +/- 10 VAC, 50 Hz, single
phase electric supply with proper
earthing. (Neutral – Earth voltage less
than 5 VAC) 5A, three pin socket with switch (2
Nos.)
Water supply
Continuous, clean and soft water
supply @ 4000 LPH, at 10 m. head.
Provide tap with 1” BSP size
connection
Space
3500Lx4000Wx2000H in mm
Drain
Provide suitable drain arrangement
(Drain pipe 65 NB/2.5” size)
Exhaust
Provide suitable exhaust arrangement
(Exhaust pipe 32 NB/1.25” size)
Foundation
As per foundation drawing
Fuel, oil
Petrol @10 liter
Oil @ 3.5 lit. (15W40)
INSTALLATION
Unpack the box(es) received and ensure that all material is received as per
packing slip (provided in instruction manual). In case of short supply or breakage
contact Apex Innovations / your supplier for further actions.
Install engine test set up assembly on the foundation.
Keep panel box structure and dash board panel near foundation (Refer foundation
drawing )
Fit the panel box assembly on the panel box structure and fit following parts
o Temperature indicator
o Load indicator
o Speed indicator
Complete the piping work as follows:
o Exhaust: Engine to calorimeter
o Water: Dynamometer inlet, outlet, Engine cooling inlet, outlet, Calorimeter
water inlet outlet and drain pipe.
o Air: Air box to engine
o Fuel: Fuel measuring unit to engine
Fit the following parts
o Pressure gauge on dynamometer inlet pipe.
o Temperature sensors (Thermocouples)
o Speed sensors on dynamometer (driving end and non driving end)
o Load cell to dynamometer.
Keep the Dashboard panel between engine and panel box. Fit the following units
and connect to engine:
o Battery
o Gauges
o Throttle unit
Complete the wiring work as follows:
Installation Commissioning
Installation requirements
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o Speed sensor to speed indicator
o Load cell to load indicator
o Temperature sensors to Temperature indicator
o Dynamometer to Dynamometer loading unit and proximity switch to DLU
COMMISSIONING
Confirm foundation bolts and propeller shaft bolts are properly tightened.
Ensure cover guard on propeller shaft and fan guard is placed.
Fill lubrication oil in the engine
Fill fuel in the fuel tank.
Remove air from fuel line connecting fuel measuring unit to fuel transmitter.
Lower jack bolts under dynamometer for free movement.
Provide electric supply to panel box
o Confirm all temperatures are correctly displayed on Temperature indicator
o Confirm load signal displayed on Load indicator
Fill water in the manometer up to “0” mark level.
Ensure water circulation through engine, calorimeter and dynamometer. The water
pressure for dynamometer should be @1 to 1.5 kg/cm^2
Press heater switch for some time and then start the Engine.
Check engine operation at various loads and ensure respective signals on
indicators.
Precautions
Use clean and filtered water; any suspended particle may clog the piping.
Circulate dynamometer cooling water for some time after shutting down the
engine.
Note: For component specific problems refer components‟ manual
Problems Possible causes / remedies
Engine does not start Water circulation pump not switched on
Discharged Battery
Check Engine wiring connector
Insufficient fuel /Air trapped in fuel line
Dynamometer may be fully loaded from DLU
Dynamometer does
not load the engine
Loose connection from DLU to dynamometer
Proximity for speed feedback not connected
Improper gap between speed feedback proximity
and rotating object. Gap should be 5-8 mm.
Engine not steady
after loading
Improper gap of speed feedback proximity sensor
connected to DLU. Gap should be 5-8 mm.
Faulty air flow Air hose leakage at connections with air-box and
with engine.
Faulty fuel flow Improper closing of fuel cock.
Faulty speed
indication
Improper gap between speed sensor and rotating
object. Gap should be 5-8 mm.
Faulty load indication Excessively raised dynamometer jack bolts
Damaged load cell due to overstressing
Incorrect
temperature
indication
Check the connection between thermocouple and
temperature indicator/transmitter. Note that yellow
cable of thermocouple is positive and red is
Troubleshooting
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negative.
Open or damaged temperature sensor
Components Details Engine Make Maruti, Model Maruti 800, Type 3 Cylinder, 4
Stroke, Petrol (MPFI), water cooled, Power 27.6Kw at
5000 rpm, Torque 59 NM at 2500rpm,stroke 72 mm,
bore 66.5mm, 796 cc,CR 9.2 Dynamometer Make Saj test plant, Model AG80, Type Eddy current Propeller shaft Make Hindustan Hardy Spicer, Model 1260, Type A Manometer Make Apex, Model MX-104, Range 100-0-100 mm,
Type U tube, Conn. 1/4`` BSP hose back side,
Mounting panel Fuel measuring unit Make Apex, Glass, Model:FF0.090 Temperature sensor Make Radix Type K, Ungrounded, Sheath
Dia.6mmX110mmL, SS316, Connection 1/4"BSP (M)
adjustable compression fitting Temperature
indicator Temperature Indicator, make ESD, model ESD 9043,
230VAC, Input Thermocouple, 6 point, Range 0-
1000deg.C. Speed indicator RPM Indicator, make Selectron, model RC 100A, Range
6000, 85 to 270VAC/DC with Photoelectric sensor, NPN
(5-30 volt DC) Load sensor Make Sensotronics Sanmar Ltd., Model 60001,Type S
beam, Universal, Capacity 0-50 kg Load indicator Load Indicator, make Selectron, model PIC 152 - B3,
85 to 270VAC/DC, Input - Load cell, Range 0-50 Kg. Dynamometer
Loading unit Make Cuadra, Model AX-153, Type veriable speed,
Supply 230V AC. with Photoelectric sensor type PNP Rotameter Make Eureka Model PG 5, Range 25-250 lph,
Connection ¾” BSP vertical, screwed, Packing
neoprene Rotameter Make Eureka, Model PG 9, Range 100-1000 lph,
Connection 1” BSP vertical, screwed, Packing neoprene Pump Pump make Kirloskar, Model KDS-128+, Head 20m.,
HP 1.0, Single phase, Size 25x25 Type Centrifugal
monoblock Battery 12 V DC
Components used
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Total no. of boxes: 10, Volume: 2.54 m3, Gross weight: 860 kg. Net wt. 684
kg
Case
No.1/10
Engine Set up Assembly
Size W1700xD800xH1200 mm; Volume:1.63m3
Gross weight: 475kg
Net weight: 475kg
1 Engine test setup assembly Engine +
Dynamometer + Base frame
1 No.
Box
No.2/10
Engine panel box
Size W990xD475xH500 mm; Volume:0.24m3
Gross weight: 78kg
Net weight: 50kg
1 Engine panel box assembly
Manometer with PU tube.
1 No.
Box
No.3/10
Engine panel box structure
Size W800xD475xH500 mm; Volume:0.19m3
Gross weight: 56kg
Net weight: 31kg
1 Engine panel box structure assembly
Rotameters with piping (2)
Dynamometer loading unit clamp (1)
1 No.
Box
No.4/10
Calorimeter
Size W650xD275xH325 mm; Volume:0.06m3
Gross weight: 45kg
Net weight: 22kg
1 Calorimeter assembly 1 No.
Box
No.5/10
Exhaust pipe
Size W900xD200xH250 mm; Volume:0.05m3
Gross weight: 17kg
Net weight: 9kg
1 Exhaust pipe 1 No.
Box
No.6/10
Pump
Size W525xD325xH425mm; Volume:0.07m3
Gross weight: 42kg
Net weight: 23kg
1 Pump 1 No.
Box
No.7/10
Battery
Size W150xD225xH250 mm; Volume:0.01m3
Gross weight: 25kg
Net weight: 17kg
1 Battery 1 No.
Box
No.8/10
Dash board
Size W500xD400xH300 mm; Volume:0.06m3
Gross weight: 32kg
Net weight: 20kg
1 Dash board panel with support structure 1 No.
2 Fuel throttle body with cable 1 No.
Box
No.9/10
Engine wiring
Size W500xD400xH300 mm; Volume:0.06m3
Gross weight: 30kg
Net weight: 12kg
1 Temperature indicator 1 No.
2 Load indicator 1 No.
3 RPM Indicator 1 No.
4 Dynamometer loading unit 1 No.
5 Pressure gauge 1 No.
6 Wiring set 1 No.
7 Load cell with nut bolt 1 No.
8 RPM sensor 1 No.
9 Temperature sensor (5) 1 No.
10 Set of loose nut bolts 1 No.
11 Tool kit 1 No.
12 Fuel caps(2), Teflon tape(2) & Gasket shellac(1) 1 No.
13 Set of instruction manuals consisting of:
Instruction manual CD (Apex)
Dynamometer
Calibration sheets for load cell
1 No.
Packing slip
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Box
No.10/1
0
Engine piping
Size W1250xD450xH350mm; Volume: 0.20m3
Gross weight: 60kg
Net weight: 25kg
1 Piping set (14 pieces)
Engine water inlet and outlet, Dynamometer
water inlet and outlet, Calorimeter water inlet
and outlet, Air hose pipe, Pump suction
connection with strainer, Pump outlet, Engine
water inlet and outlet hose, Water supply hose
pipe, Drain pipe (3 components)
1 No.
2 Water supply pipe 1.25” hose 1 No.
3 Load cell bracket 1 set
4 Fuel measuring unit 2Nos (one spare) 1 No.
5 Wiring channel set 1 No.
6 Engine air connection pipe 1 No.
7 Fuel filter assembly 1 No.
8 Exhaust extension pipe with socket and bend 1 No.
9 Pump bracket 1 No.
10 Air box connection 1 No.
11 Calorimeter exhaust outlet flange 1 No.
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This product is warranted for a period of 12 months from the date of supply against
manufacturing defects. You shall inform us in writing any defect in the system
noticed during the warranty period. On receipt of your written notice, Apex at its
option either repairs or replaces the product if proved to be defective as stated
above. You shall not return any part of the system to us before receiving our
confirmation to this effect.
The foregoing warranty shall not apply to defects resulting from:
Buyer/ User shall not have subjected the system to unauthorized alterations/
additions/ modifications.
Unauthorized use of external software/ interfacing.
Unauthorized maintenance by third party not authorized by Apex.
Improper site utilities and/or maintenance.
We do not take any responsibility for accidental injuries caused while working with
the set up.
Apex Innovations Pvt. Ltd. E9/1, MIDC, Kupwad, Sangli-416436 (Maharashtra) India
Telefax:0233-2644098, 2644398
Email: [email protected] Web: www.apexinnovations-ind.com
Warranty
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TERMINOLOGY Engine Cylinder diameter (bore) (D): The nominal inner diameter of the
working cylinder.
Piston area (A): The area of a circle of diameter equal to engine
cylinder diameter (bore). 24/ DA
Engine Stroke length (L): The nominal distance through which a working
piston moves between two successive reversals of its direction of motion.
Dead center: The position of the working piston and the moving parts, which
are mechanically connected to it at the moment when the direction of the piston
motion is reversed (at either end point of the stroke).
Bottom dead center (BDC): Dead center when the piston is nearest to
the crankshaft. Sometimes it is also called outer dead center (ODC).
Top dead center (TDC): Dead center when the position is farthest from the
crankshaft. Sometimes it is also called inner dead center (IDC).
Swept volume (VS): The nominal volume generated by the working piston
when travelling from one dead center to next one, calculated as the product of
piston area and stroke. The capacity described by engine manufacturers in cc
is the swept volume of the engine. LDLAVs
24/
Clearance volume (VC): The nominal volume of the space on the combustion side
of the piston at top dead center.
Cylinder volume: The sum of swept volume and clearance volume. cs VVV
Compression ratio (CR): The numerical value of the cylinder volume divided
by the numerical value of clearance volume. cVVCR /
Theory
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Bore D
Crankshaft
Crankcase
Crank
Crank pin
Connecting rod
Cylinder
Bottom dead center B.D.C.
Piston
Gudgeon or wrist pin
Top dead center T.D.C.
Intake or suction manifold
Suction valve
Exhaust manifold
Exhaust valve
Cylinder head
Stroke volume.Vs
Clearance volume.Vc
Cylinder volume’V’
Important positions and volumes in reciprocating engine
Four stroke cycle engine In four-stroke cycle engine, the cycle of operation is completed in four strokes of the
piston or two revolutions of the crankshaft. Each stroke consists of 1800 of crankshaft
rotation and hence a cycle consists of 7200 of crankshaft rotation. The series of
operation of an ideal four-stroke engine are as follows:
1. Suction or Induction stroke: The inlet valve is open, and the piston travels
down the cylinder, drawing in a charge of air. In the case of a spark ignition
engine the fuel is usually pre-mixed with the air.
2. Compression stroke: Both valves are closed, and the piston travels up the
cylinder. As the piston approaches top dead centre (TDC), ignition occurs. In the
case of compression ignition engines, the fuel is injected towards the end of
compression stroke.
3. Expansion or Power or Working stroke: Combustion propagates throughout
the charge, raising the pressure and temperature, and forcing the piston down.
At the end of the power stroke the exhaust valve opens, and the irreversible
expansion of the exhaust gases is termed „blow-down‟.
4. Exhaust stroke: The exhaust valve remains open, and as the piston travels up
the cylinder the remaining gases are expelled. At the end of the exhaust stroke,
when the exhaust valve closes some exhaust gas residuals will be left; these will
dilute the next charge.
Two stroke cycle engine In two stroke engines the cycle is completed in two strokes of piston i.e. one
revolution of the crankshaft as against two revolutions of four stroke cycle engine.
The two-stroke cycle eliminates the separate induction and exhaust strokes.
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1. Compression stroke: The piston travels up the cylinder, so compressing the
trapped charge. If the fuel is not pre-mixed, the fuel is injected towards the end
of the compression stroke; ignition should again occur before TDC.
Simultaneously under side of the piston is drawing in a charge through a spring-
loaded non-return inlet valve.
2. Power stroke: The burning mixture raises the temperature and pressure in the
cylinder, and forces the piston down. The downward motion of the piston also
compresses the charge in the crankcase. As the piston approaches the end of its
stroke the exhaust port is uncovered and blowdown occurs. When the piston is at
BDC the transfer port is also uncovered, and the compressed charge in the
crankcase expands into the cylinder. Some of the remaining exhaust gases are
displaced by the fresh charge; because of the flow mechanism this is called „loop
scavenging'. As the piston travels up the cylinder, the piston closes the first
transfer port, and then the exhaust port is closed.
Performance of I.C.Engines Indicated thermal efficiency (ηt): Indicated thermal efficiency is the ratio of
energy in the indicated power to the fuel energy.
FuelEnergyowerIndicatedPt /
100)/()/(
3600)((%)
KgKJalueCalorificVHrKgFuelFlow
KWowerIndicatedPt
Brake thermal efficiency (ηbth): A measure of overall efficiency of the engine
is given by the brake thermal efficiency. Brake thermal efficiency is the ratio of
energy in the brake power to the fuel energy.
FuelEnergyBrakePowerbth /
100)/()/(
3600)((%)
KgKJalueCalorificVHrKgFuelFlow
KWBrakePowerbth
Mechanical efficiency (ηm): Mechanical efficiency is the ratio of brake horse power
(delivered power) to the indicated horsepower (power provided to the piston).
owerIndicatedPBrakePowerm /
and Frictional power = Indicated power – Brake power
Following figure gives diagrammatic representation of various efficiencies,
Energy lost in exhaust, coolant, and radiation
Energy lost in friction, pumping etc.
Energy
in fuel (A)
IP (B)
BP (C)
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Indicated thermal efficiency = B/A
Brake thermal efficiency = C/A
Mechanical efficiency = C/B
Volumetric efficiency (ηv): The engine output is limited by the maximum
amount of air that can be taken in during the suction stroke, because only a
certain amount of fuel can be burned effectively with a given quantity of air.
Volumetric efficiency is an indication of the „breathing‟ ability of the engine and
is defined as the ratio of the air actually induced at ambient conditions to the
swept volume of the engine. In practice the engine does not induce a complete
cylinder full of air on each stroke, and it is convenient to define volumetric
efficiency as:
Mass of air consumed
ηv (%) = --------------------------------------------------------------------------
mass of flow of air to fill swept volume at atmospheric conditions
10060)/(/)()(4/
)/((%)
332
mKgAirDenNoofCylnRPMNmLD
HrKgAirFlowv
Where n= 1 for 2 stroke engine and n= 2 for 4 stroke engine.
Air flow:
For air consumption measurement air box with orifice is used.
3600/24/)/( 2 dendendenwaterd AAWhgDCHrKgAitFlow
Where Cd = Coefficient of discharge of orifice
D = Orifice diameter in m
g = Acceleration due to gravity (m/s2) = 9.81 m/s2
h = Differential head across orifice (m of water)
Wden = Water density (kg/m3) =@1000 kg/m3
Wair = Air density at working condition (kg/m3) = p/RT
Where
p= Atmospheric pressure in kgf/m2 (1 Standard atm. = 1.0332X104 kgf/m2)
R= Gas constant = 29.27 kgf.m/kg0k
T= Atmospheric temperature in 0k
Specific fuel consumption (SFC): Brake specific fuel consumption and indicated
specific fuel consumption, abbreviated BSFC and ISFC, are the fuel consumptions
on the basis of Brake power and Indicated power respectively.
Fuel-air (F/A) or air-fuel (A/F) ratio: The relative proportions of the fuel and air
in the engine are very important from standpoint of combustion and efficiency of
the engine. This is expressed either as the ratio of the mass of the fuel to that of
the air or vice versa.
Calorific value or Heating value or Heat of combustion: It is the energy
released per unit quantity of the fuel, when the combustible is burned and the
products of combustion are cooled back to the initial temperature of combustible
mixture. The heating value so obtained is called the higher or gross calorific value
of the fuel. The lower or net calorific value is the heat released when water in the
products of combustion is not condensed and remains in the vapour form.
Power and Mechanical efficiency: Power is defined as rate of doing work and
equal to the product of force and linear velocity or the product of torque and
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angular velocity. Thus, the measurement of power involves the measurement of
force (or torque) as well as speed.
The power developed by an engine at the output shaft is called brake power and
is given by
Power = NT/60,000 in kW
where T= torque in Nm = WR
W = 9.81 * Net mass applied in kg. R= Radius in m
N is speed in RPM
Mean effective pressure and torque: Mean effective pressure is defined as a
hypothetical pressure, which is thought to be acting on the piston throughout the
power stroke.
Power in kW = (Pm LAN/n 100)/60 in bar
where Pm = mean effective pressure
L = length of the stroke in m
A = area of the piston in m2
N = Rotational speed of engine RPM
n= number of revolutions required to complete one engine cycle
n= 1 (for two stroke engine)
n= 2 (for four stroke engine)
Thus we can see that for a given engine the power output can be measured in
terms of mean effective pressure. If the mean effective pressure is based on
brake power it is called brake mean effective pressure (BMEP) and if based on
indicated power it is called indicated mean effective pressure (IMEP).
100)/(
60)()(
NoOfCylnNAL
KWBrakePowerbarBMEP
100)/(
60)()(
NoOfCylnNAL
KWowerIndicatedPbarIMEP
Similarly, the friction means effective pressure (FMEP) can be defined as
FMEP= IMEP – BMEP
Basic measurements The basic measurements, which usually should be undertaken to evaluate the
performance of an engine on almost all tests, are the following:
1 Measurement of speed Following different speed measuring devices are used for speed measurement.
1 Photoelectric/Inductive proximity pickup with speed indicator
2 Rotary encoder
2 Measurement of fuel consumption I) Volumetric method: The fuel consumed by an engine is measured by
determining the volume flow of the fuel in a given time interval and multiplying it by
the specific gravity of fuel. Generally a glass burette having graduations in ml is used
for volume flow measurement. Time taken by the engine to consume this volume is
measured by stopwatch.
II) Gravimetric method: In this method the time to consume a given weight of the
fuel is measured. Differential pressure transmitters working on hydrostatic head
principles can used for fuel consumption measurement.
3 Measurement of air consumption Air box method: In IC engines, as the air flow is pulsating, for satisfactory
measurement of air consumption an air box of suitable volume is fitted with orifice.
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The air box is used for damping out the pulsations. The differential pressure across
the orifice is measured by manometer and pressure transmitter.
4 Measurement of brake power Measurement of BP involves determination of the torque and angular speed of the
engine output shaft. This torque-measuring device is called a dynamometer.
The dynamometers used are of following types:
I) Rope brake dynamometer: It consists of a number of turns of rope wound
around the rotating drum attached to the output shaft. One side of the rope is
connected to a spring balance and the other to a loading device. The power is
absorbed in friction between the rope and the drum. The drum therefore requires
cooling.
Brake power = ∏DN (W-S)/60,000 in kW
where D is the brake drum diameter, W is the weight and S is the spring scale
reading.
II) Hydraulic dynamometer: Hydraulic dynamometer works on the principal of
dissipating the power in fluid friction. It consists of an inner rotating member or
impeller coupled to output shaft of the engine. This impeller rotates in a casing, due
to the centrifugal force developed, tends to revolve with impeller, but is resisted by
torque arm supporting the balance weight. The frictional forces between the impeller
and the fluid are measured by the spring-balance fitted on the casing. Heat
developed due to dissipation of power is carried away by a continuous supply of the
working fluid usually water. The output (power absorbed) can be controlled by
varying the quantity of water circulating in the vortex of the rotor and stator
elements. This is achieved by a moving sluice gate in the dynamometer casing.
III) Eddy current dynamometer: It consists of a stator on which are fitted a
number of electromagnets and a rotor disc and coupled to the output shaft of the
engine. When rotor rotates eddy currents are produced in the stator due to magnetic
flux set up by the passage of field current in the electromagnets. These eddy
currents oppose the rotor motion, thus loading the engine. These eddy currents are
dissipated in producing heat so that this type of dynamometer needs cooling
arrangement. A moment arm measures the torque. Regulating the current in
electromagnets controls the load.
Note: While using with variable speed engines sometimes in certain speed zone the
dynamometer operating line are nearly parallel with engine operating lines which
result in poor stability.
5 Measurement of indicated power
There are two methods of finding the IHP of an engine.
I) Indicator diagram: A dynamic pressure sensor (piezo sensor) is fitted in the
cylinder head to sense combustion pressure. A rotary encoder is fitted on the engine
shaft for crank angle signal. Both signals are simultaneously scanned by an engine
indicator (electronic unit) and communicated to computer. The software in the
computer draws pressure crank-angle and pressure volume plots and computes
indicated power of the engine.
Conversion of pressure crank-angle plot to pressure volume plot:
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The figure shows crank-slider mechanism. The piston pin position is given by
coscos lrx
From figure sinsin lr and recalling 2sin1cos
22
sin1cos lrrlrx
The binomial theorem can be used to expand the square root term:
...sin)/(81sin)/(2
11/cos 4422 lrlrrlrx ….1
The powers of sin can be expressed as equivalent multiple angles:
2cos2/12/1sin2
4cos8/12cos2/18/3sin 4 …….2
Substituting the results from equation 2 in to equation 1 gives
...4cos8/12cos2/18/3)/(812cos2/12/1)/(2
11/cos 42 lrlrrlrx
The geometry of the engine is such that 2/ lr is invariably less than 0.1, in which
case it is acceptable to neglect the 4/ lr terms, as inspection of above equation
shows that these terms will be at least an order of magnitude smaller than 2/ lr
terms.
The approximate position of piston pin end is thus:
2cos2/12/1)/(2
11/cos 2 lrrlrx
Where r =crankshaft throw and l = connecting rod length.
Calculate x using above equation; then )( xrl shall give distance traversed by
piston from its top most position at any angle
II) Morse test: It is applicable to multi-cylinder engines. The engine is run at
desired speed and output is noted. Then combustion in one of the cylinders is
stopped by short circuiting spark plug or by cutting off the fuel supply. Under this
condition other cylinders “motor” this cylinder. The output is measured after
adjusting load on the engine to keep speed constant at original value. The difference
in output is measure of the indicated power of cut-out cylinder. Thus for each
cylinder indicated power is obtained to find out total indicated power.
a) When Cylinder no. 1 is in motoring:
Output BP = Indicated power of Cylinder no. 2 + IP of cylinder no. 3 – Frictional
power of cyl 1 – FP of cyl2 – FP of cyl 3
BP1 = IP2+IP3-FP1-FP2-FP3
BP1 = IP2+IP3-FP ------------I
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Where BP1 is Brake power when cyl no1 is cut off, FP is total frictional power for all 3
cylinders.
Similarly
BP2= IP1+IP3-FP--------------II
and BP3 = IP1+IP2-FP--------------III
b) When all working
BP = IP1+IP2+IP3 – FP
BP=IP1 + (IP2+IP3 – FP)
BP = IP1 + BP1 (from eqn I)
IP1 = BP - BP1 --------------------IV
similarly
IP2 = BP - BP2 --------------------V
IP3 = BP - BP3 --------------------VI
Add IP1, IP2 and IP3 to get total IP
Then IP – BP = FP
And mech eff = BP/IP
VCR Engines The standard available engines (with fixed compression ratio) can be modified by
providing additional variable combustion space. This is done by welding a long hollow
sleeve with internal threads to the engine head. A threaded plug is inserted in the
sleeve to vary the combustion chamber volume. With this method the compression
ratio can be changed within designed range.
Calculations
Brake power (kw):
100060
2
x
NTBP
60000
)(2 WxRN
60000
)81.9(785.0 xArmlengthWxxRPMx
6075x
TxNBHP
Brake mean effective pressure (bar):
100)/(4/
602 xNoOfCylxnNxLxxD
BPxBMEP
n = 2 for 4 stroke
n = 1 for 2 stroke
Indicated power (kw) :From PV diagram
X scale (volume) 1cm = ..m3
Y scale (pressure) 1cm = ..bar
Area of PV diagram = ..cm2
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100000)(// orYscalefactorXscalefactagramAreaofPVdiNmcylcycleworkdone
100060
)/(//
NoOfCylnNcylcycleworkdoneIP
Indicated mean effective pressure (bar):
100)/(4/
602 xNoOfCylxnNxLxxD
IPxIMEP
Frictional power (kw):
BPIPFP
BHPIHPFHP
FHPIHPBHP
Brake specific fuel consumption (Kg/kwh):
BP
hrkgFuelflowInBSFC
/
Brake Thermal Efficiency (%):
CalValhrKgFuelFlowIn
BPBThEff
/
1003600
FuelHP
BHPOR
MechEffIThEffBThEff
100
Indicated Thermal Efficiency (%):
CalValhrKgFuelFlowIn
IPIThEff
/
1003600
MechEff
BThEffIThEff
100
Mechanical Efficiency (%):
IP
BPMechEff
100
Air flow (Kg/hr):
AdenAdenWdenghdCdAirFlow 3600)/(24/ 2
Volumetric Efficiency (%):
lAirFlowTheoretica
AirFlowVolEff
100
AdenNoOfCylnNStrokeD
AirFlow
60)/(4/
1002
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Air fuel ratio:
FuelFlow
AirFlowFA /
Heat Balance (KJ/h):
a) CalValFuelFlowedbyFuelHeatSuppli
b) 3600 BPulWorklentToUsefHeatEquiva
edByFuelHeatSuppli
ulWorklentToUsefHeatEquivaulWorkInlentToUsefHeatEquiva
100%
C) )12(3 TTWCFateretCoolingWHeatInJack P
edByFuelHeatSuppli
ateretCoolingWHeatInJackaterInetCoolingWHeatInJack
100%
d) Heat in Exhaust (Calculate CPex value):
kKgKJTTFF
TTWCFexC P
P
0/..)65()21(
)34(4
Where,
Cpex Specific heat of exhaust gas kJ/kg0K
Cpw Specific heat of water kJ/kg0K
F1 Fuel consumption kg/hr
F2 Air consumption kg/hr
F4 Calorimeter water flow kg/hr
T3 Calorimeter water inlet temperature 0K
T4 Calorimeter water outlet temperature 0K
T5 Exhaust gas to calorimeter inlet temp. 0K
T6 Exhaust gas from calorimeter outlet temp. 0K
)5()21()/( TambTexCFFhKJustHeatInExha P
edByFuelHeatSuppli
ustHeatInExhaustHeatInExha
100%
e) Heat to radiation and unaccounted (%)
(%)}(%)
(%){(%)100(
ustHeatToExhaateretCoolingWHeatInJack
ulWorklentToUsefHeatEquivaedByFuelHeatSuppli
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1 Study of engine performance (Manual mode) Object
To study the performance of 3 cylinder, 4 stroke, Petrol engine connected to Eddy
current dynamometer in manual mode
Procedure
Ensure cooling water circulation for Eddy current dynamometer, engine and
calorimeter.
Start the set up and run the engine at no load for 4-5 minutes.
Gradually increase the load on the engine by rotating dynamometer loading
unit nob.
Wait for steady state (for @ 3 minutes) and collect the reading as per
Observations provided in “Cal231” worksheet.
Gradually decrease the load.
Fill up the observations in “Cal231” worksheet to get the results and
performance plots.
2 Study of Morse test Object
To study Morse test
Procedure
Ensure cooling water circulation for dynamometer, engine and calorimeter.
Start the set up and run the engine at no load for 4-5 minutes.
Gradually increase the load on the engine from dynamometer loading unit.
Increase the engine throttle to any desired position and simultaneously load
the engine to obtain desired speed for which frictional power is to be
calculated.
Wait for few minutes till steady state is achieved. Note Engine speed and
load.
Cut off the fuel supply of cylinder no. 1 by pushing the push button "Cyl1"
from Morse test panel. The engine speed shall decrease. Now decrease the
load on dynamometer and bring back engine speed to the original.
Wait for steady state (for @ 3 minutes) and collect the reading
Repeat the same for "Cyl2" and "Cyl3".
Fill up the readings is the Observations provided in “Cal231” worksheet in
“Engine.xls”.
Gradually decrease the load and throttle and Stop the engine.
Experiments
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Rotameter (PG series) Rotameter works on the principle of variable area. Float is free to move up & down in
a tapered measuring glass tube. Upward flow causes the float to take up a position in
which the buoyancy forces and the weight are balanced. The vertical position of the
float as indicated by scale is a measurement of the instantaneous flow rate.
Technical specifications Model PG-1 to 21
Make Eureka Industrial Equipments
Pvt. Ltd.
Flow Rate Max. 4000 to 40000 Lph
Packing/Gaskets Neoprene
Measuring tube Borosilicate glass
Float 316SS
Cover Glass
Accuracy +/-2% full flow
Range ability 10:1
Scale length 175-200mm.
Max. Temp. 2000C
Connection Flanged and Threaded, Vertical
Principle of operation
The rotameter valves must be opened slowly and carefully to
adjust the desired flow rate. A sudden jumping of the float,
which may cause damage to the measuring tube, must be avoided.
Edge
Fig.1
The upper edge of the float as shown in fig. 1 indicates the rate of flow. For
alignment a line marked R.P. is provided on the scale which should coincide with the
red line provided on measuring tube at the bottom.
Maintenance
When the measuring tube and float become dirty it is necessary to remove the tube
and clean it with a soft brush, trichloroethylene or compressed air.
Dismantling of the measuring tube
Shut off the flow.
Remove the front and rear covers.
Unscrew the gland adjusting screws, and push the gland upwards incase of bottom
gland and downwards incase of top gland. Then remove the glass by turning it to
and fro. Care should be taken, not to drop down the glands. Float or float
retainers. The indicating edge of the float should not be damaged.
Components
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Fitting of the measuring tube
Normally the old gland packing is replaced by new ones while fitting back the
measuring tube.
Put the glands first in their position and then put the packing on the tube.
Insert the tube in its place.
Push the glands downwards and upwards respectively and fix them with the gland
adjusting screws.
Tighten the gland adjusting screws evenly till the gap between the gland and the
bottom plate is approximately 1mm. In case, after putting the loflometer into
operation, still there is leakage, then tighten the gland adjusting screw till the
leakage stops.
Fix the scale, considering the remark given in the test report.
Fix the front and rear covers. Troubleshooting Problem Check
Leakage on glands Replace gland packing
Showing high/low flow rate than
expected
Consult manufacturers
Showing correct reading initially but
starts showing high reading after
few days
Replace float
Incase of gases, check also leakage
Showing correct reading initially but
starts showing high reading after
some months.
Clean the rotameter by suitable solvent or
soft brush
Fluctuation of float Maintain operating pressure as mentioned
in test report.
Frequent breakage of glass tube Use loflometer to accommodate correct
flow rate.
Maintain operating pressure below
pressure rating of the tube.
Check piping layout.
Manufacturer’s address If you need any additional details, spares or service support for this unit you may
directly communicate to the manufacturer / Dealer / Indian Supplier.
Eureka Industrial Equipments Pvt. Ltd.
17/20, Royal Chambers,
Paud Road, Pune – 411 038.
Email: [email protected]
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Load cell
Introduction Load cell are suitable use for static & dynamic
weighing, bin/hopper weighing, force measurement,
scales and electro-mechanical conversion kit.
Constructed body of special high alloy steel.
Approved for group I, IIA, IIB, & IIC applications
and meets temperature class T4.
Technical specifications Make Sensortronics
Model 60001
Type „S‟ Beam, Universal
Capacity 0 – 50Kg
Mounting thread M10 x 1.25mm
Full scale output (mV/V) 3.00
Tolerance on output (FSO) +/-0.25%
Zero balance (FSO) +/-0.1mV/V
Non-linearity (FSO) <+/-0.025%
Hysteresis (FSO) <+/-0.020%
Non-repeatability <+/-0.010%
Creep (FSO) in 30 min <+/-0.020%
Operating temperature range -200C to +700C
Rated excitation 10V AC/DC
Maximum excitation 15V AC/DC
Bridge resistance 350 Ohms (Nominal)
Insulation resistance >1000 Meg ohm @ 50VDC
Span / 0C (of load) +/-0.001%
Zero / 0C (of FSO) +/-0.002%
Combined error (FSO) <+/-0.025%
Safe overload (FSO) 150%
Ultimate overload (FSO) 300%
Protection class IP 67
Overall dimensions 51 L x 20 W x 76 H mm
Weight 380 gm
Manufacturer’s address If you need any additional details, spares or service support for this unit you may
directly communicate to the manufacturer / Dealer / Indian Supplier.
Sensortronics Sanmar Ltd.
38/2A, Old Mahabalipuram Road,
Perungudi, Chennai – 600 096.
E-mail: [email protected]
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RPM indicator with sensor
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Load indicator
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