If you can't read please download the document

View

118Download

2

Tags:

Embed Size (px)

DESCRIPTION

basic fluid mechanics laboratory experiments

HIGHER COLLEGE OF TECHNOLOGY, MUSCAT

Engineering DepartmentMECHANICAL SECTION

FLUID MECHANICS LAB

MIME 2240P FLUID MECHANICS3 Credit Hours Pre-requisites: Phys1210, MATH 3100

GOAL: To impart essential knowledge of Fluid Mechanics and related equipments as applicable to the Mechanical Engineering industry.

OBJECTIVESThe course should enable students to: 1. Understand the basic properties and principles that govern the behavior of fluids. 2. Understand application of devices used for measurement of fluid properties. 3. Solve simple problems of hydrostatics and fluid flow. 4. Gain knowledge of the various types of fluid pumps, gas(air) compressors and valves commonly used in Mechanical Engineering industries.

OUTCOMESUpon completion of the course, the students will be able to: 1. Solve simple problems of hydrostatics. 2. Solve simple problems of fluid flow in pipes using Continuity equation and Bernoullis equation. 3. Be acquainted with the use of common pressure, flow & temperature measuring devices used for hydrostatic and pipe flow applications.

OUTCOMES

part2

4. Develop basic knowledge of construction and operation of various types of liquid pumps. 5. Develop the basic knowledge of construction and operation of various types of gas compressors. 6. Gain familiarization with different types of valves used in Mechanical Engineering industries.

BASIC DEFINITIONFluid mechanics is the study of how fluids move and the forces on them. Fluids include liquids and gases.

Fluid mechanics can be divided into fluid statics, the study of fluids at rest, and fluid dynamics, the study of fluids in motion.

A fluid is defined as a substance that continually deforms (flows) under an applied shear stress regardless of how small the applied stress. All liquids and all gases are fluids.

Distinction between Gas & Liquid: The molecules of a GAS is much farther apart than those of a LIQUID. Hence a GAS is very compressible, and when all external pressure is removed, it tends to expands indefinitely. GAS therefore is in equilibrium only when it is completely enclosed.

LIQUID is relatively incompressible, & if all pressure, except that of its own vapor pressure, is removed, the cohesion between molecules holds them together, so that the liquid doesnt expand indefinitely. Therefore a liquid may have a free surface, i.e. a surface from which all pressure is removed, except that of its own vapor.

What is the difference between: VAPOR GAS STEAM

VAPOR is a gas whose temperature & pressure are such that it is very near liquid phase. Steam is considered vapor, its state is normally not far from that of water. GAS may be defined as a high super heated vapor; i.e., its state is far removed from the liquid phase. Thus air is considered a gas, its state is normally far from liquid air.

DEVICES IN MEASUREMENT FLUID PROPERTIES

BOURDON GAUGE

BOURDON GAUGE

(SCHEMATIC)

SOLVE SIMPLE PROBLEMS

VARIOUS INDUSTRIAL PUMPS

VARIOUS INDUSTRIAL PUMPS part2

DETAILED PARTS LIST OF A RECIPROCATING COMPRESSOR

MOTOR WITH THE MAGNETIC COILS

INSIDE A RECIPROCATING COMPRESSOR

CLOSER LOOK OF THE PISTON HEAD

VARIOUS VALVES

SCHEMATIC AND ACTUAL PIPING SYSTEM

VALVES, GAUGES & PIPING SYSTEM IN OIL & GAS FIELDS

INDUSTRIAL MOTOR & CENTRIFUGAL PUMP

CENTRIFUGAL PUMP

EXPLODED VIEW & ASSEMBLY OF A CENTRIFUGAL PUMP

DEEP WELL PUMP

PUMPING OIL & GAS

ELECTRICAL SUBMERSIBLE PUMPS

LABORATORY REPORT FORMAT I. COVER SHEET II. INTRODUCTION What you did? How you did it? Definition of Technical Terms III. PROCEDURE Step by step on how you did the experiment (in your own words, include safety) Identification of Equipments & Apparatus being used In the experiment

LABORATORY REPORT FORMAT page2 IV. COMPUTATIONS / DISCUSSIONS Show Conversion of Units Show Formulas being Used Computations of Error V. GRAPHS/CHARTS/TABLE In Excel Format VI. CONCLUSION/REMARKS/APPLICATION How can you Apply the Experiment in your Field of Specialization

STUDENT SAFETY RULESIt is important that the students observe and carry out the safety instruction at all times in laboratory environment. The following instructions highlight the more obvious points of safety.

STUDENT SAFETY RULES1. Every student should wear proper Personal Protective Equipments (PPE). a. Cover-all for male students b. Lab-coat for female students

Experiment #1 Measuring Liquid Densities

OBJECTIVE To understand the basic properties and principles that govern the behavior of fluids. To familiarized basic fluid measuring devices. To properly understand how to read measurement of fluids. To differentiate Density, Specific Gravity and Relative Density.

Apparatus for Experiment #1

Measuring Cylinders

Apparatus for Experiment #1

Different Liquids

Apparatus for Experiment #1

Triple Beam Balance

Weight (Fg) measure of gravitational force measure on a substance. In another word, gravity is the force that cause weight. Fg = m * (g / gc) where g = local gravitational acceleration gc = 9.8066 m/s2 (constant)

Mass, m the absolute quantity of a matter (solid, liquid & gas). Local gravitational acceleration, g at sea level is also equal to 9.8066 m/s2, therefore at sea level weight is equal to mass (Fg = m only at sea level). But if you are in a higher place g changes (decreases) and therefore weight changes & its not anymore equal to mass (constant). (Fg m at higher / lower than sea level).

Density (mass density) (rho), is the mass per unit volume.

=m/V

Specific Weight (gamma) (also known as weight density) this is the weight (force exerted by gravity) of a substance per unit volume. = Fg / V but Fg = m * g & = m/v

so that = * (g / gc)

Therefore at sea level only

=

Specific gravity (SG) is a ratio of the mass of a material to the mass of an equal volume of water at 4oC (39oF). Because specific gravity is a ratio, it is a unitless quantity.

HYDROMETERSThe specific gravity of a liquid can be determined with a hydrometer, a hollow, sealed, calibrated glass tube. The depth to which the hydrometer sinks is inversely proportional to the specific gravity of the liquid.

In the closeup below, we see that the specific gravity of the blue liquid is 1.016.

How to properly read the fluid measurement in glass tubes or cylinders

Relative density (RD) is essentially the same as specific gravity, however the temperature used for the water (or even another material) is not necessarily 4oC.

For most materials, the volume change going from 4oC to room temperature (20oC, typically) is not very large. Therefore, we often use the terms density and specific gravity interchangeably as these values will not differ by more than 1% or 2% in most cases.

Another use for specific gravity is to tell us if the material will sink or float in water or other liquid (assuming that it does not dissolve, of course). For example, a rock with a density of 4.3 g/cm3 will sink in water (density = 1.0 g/cm3), but a piece of plastic with a density of 0.8 g/cm3 will float in water.

Remember the following: If we have two equal volumes of a substance, the one with the larger density will be heavier. If we have two equal masses of a substance, the one with the larger density will occupy less space (volume).

Densities of some common materials: Gasoline (0.75 gm/cm3) Engine oil (0.893 gm/cm3) Visco2000 Engine oil (0.895 kg/liter) Rotella TX Coconut oil (0.919 gm/cm3) @ 15oC Coconut oil (0.925 gm/cm3) @ 20oC Lead (11.3 gm/cm3) Mercury (13.5 gm/cm3) Gold (19.3 gm/cm3)The densest material on Earth (not counting subatomic particles) is iridium metal (22.65 gm/cm3)

Procedure: Using the triple beam balance weighing scale, compute for the mass of the various liquids in different temperature scale. This is done by first weighing the empty measuring beaker, recording it. Then fill with a defined volume of various liquids and weigh again. Having the total (beaker plus fluid) minus the weight of the empty beaker, you can find the weight of the liquid substance. Now convert this weight into mass, using gravitational acceleration, g equal to 9.906 meter per square second.

Procedure: Using the thermometer, take the initial temperature and final temperature, then take the average of these 2 temperature. Now calculate the density of each liquid, check for the consistency of units. Record each in the table provided. For each liquid substance, do at least three (3) trials each in using the weighing scale. Record also the temperature of these different liquids. Given the theoretical density of some liquids, calculate the percent error of these liquid substances. Repeat the above steps for the others liquids.

Conversion of units of volume ml (milli-liter) to m3 (cubic meter) (1ml)x(liter/1000ml)x(m3/1000liter) Or simply (1ml)x(1x10-6 m3/ml)

Conversion of units of density from gm/cm3 into kg/m3 just multiply by 1,000 from kg/liter into gm/cm3 it is equal, since 1 milli-liter (ml) is equal 1 cubic centimeter (cc) or simply 1ml = 1cc

Percent Error, %E: Experimental Theoretical x 100 Theoretical

Some of the sources of potential error in highprecision balances or mechanical scales include the following:

Bouyancy, because the object being weighed displaces a certain amount of air, which must be accounted for. High-precision balances are often operated in a vacuum. Error in reference weight. Air gusts, even small ones, which push the scale up or down. Mis-aligned mechanical components.

Fric