Fluid Lab Expt

FLUID MECHANICS LAB

HIGHER COLLEGE OF TECHNOLOGY, MUSCAT

Engineering Department MECHANICAL SECTION

MIME 2240P FLUID MECHANICS

3 Credit HoursPre-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.

OUTCOMES

Upon 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 Bernoulli’s 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.

Fluid mechanics is the study of

how fluids move and the forces

on them.

Fluids include liquids and gases.

BASIC DEFINITION

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 doesn’t 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 PROPERTIESBOURDON GAUGE

BOURDON GAUGE (SCHEMATIC)

SOLVE SIMPLE PROBLEMS

VARIOUS INDUSTRIAL PUMPS

VARIOUS INDUSTRIAL PUMPS part2

DETAILED PARTS LIST OF A RECIPROCATING COMPRESSOR

INSIDE A RECIPROCATING COMPRESSOR

MOTOR WITH THE MAGNETIC COILS

CLOSER LOOK OF THE PISTON HEAD

VARIOUS VALVES

SCHEMATIC AND ACTUAL

PIPING SYSTEM

VALVES, GAUGES & PIPING SYSTEMIN OIL &

GAS FIELDS

INDUSTRIAL MOTOR & CENTRIFUGAL PUMP

CENTRIFUGAL PUMP

EXPLODED VIEW & ASSEMBLY OF A CENTRIFUGAL PUMP

DEEP WELL PUMP

ELECTRICAL SUBMERSIBLE PUMPS

PUMPING OIL & GAS

LABORATORY REPORT FORMAT

I. COVER SHEET

II. INTRODUCTIONWhat you did? How you did it?Definition of Technical Terms

III. PROCEDUREStep 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 / DISCUSSIONSShow Conversion of UnitsShow Formulas being UsedComputations of Error

V. GRAPHS/CHARTS/TABLEIn Excel Format

VI. CONCLUSION/REMARKS/APPLICATIONHow can you Apply the Experiment in

your Field of Specialization

STUDENT SAFETY RULES

It 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 RULES

1. Every student should wear proper Personal Protective Equipments (PPE).a. Cover-all for male studentsb. 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.

Measuring Cylinders

Apparatus for Experiment #1


Different Liquids


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 accelerationgc = 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 & it’s not anymore equal to mass (constant). (Fg ≠ m at higher / lower than sea level).

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

ρ = m / V

Specific Weight ɣ (gamma) (also known as weight density)– this is the weight (force exerted by gravity) of a substance per unit volume.

ɣ = Fg / V but Fg = m * g & ρ = m / v

so that ɣ = ρ * (g / gc)

Therefore at sea level only ɣ = ρ

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) Visco2000Engine oil (0.895 kg/liter) Rotella TXCoconut oil (0.919 gm/cm3) @ 15oCCoconut oil (0.925 gm/cm3) @ 20oCLead (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(1x10-6m3/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 100Theoretical

Some of the sources of potential error in high-precision 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.

•Friction in the moving components that prevents the scale from reaching equilibrium

•Settling airborne dust contributing to the weight.

•Mis-calibration

•The calibration of electronic circuits may drift over time, or due to temperature changes.

•Due to thermal expansion/contraction of components of the balance.

•Magnetic field acting on iron components.

•The Earth's magnetic field •Fields from nearby electrical wiring

•Magnetic disturbances to electronic pick-up coils or other sensors

•Forces from electrostatic fields, for example, from feet shuffled on carpets on a dry day. •Chemical reactivity between air and the substance being weighed (or the balance itself, in the form of corrosion).

•Condensation of atmospheric water on cold items.

•Evaporation of water from wet items

•Convection of air from hot or cold items •The Coriolis force from Earth's rotation •Gravitational anomalies (i.e. using the balance near a mountain; failing to level and recalibrate the balance after moving it from one geographical location to another)

•Vibration and seismic disturbances; for example, the rumbling from a passing truck or concrete mixers, etc.

Experiment #2

Measurement of Liquid Viscosity Using Falling

Sphere Viscometer

OBJECTIVES

• Measure the viscosity of various fluids contained in a vertical tube by measuring the terminal velocity of spherical balls falling through the various fluids.

• Be able to calculate the viscosity of an unknown liquid using Stoke’s law.

• Determine the drag coefficient vs. Reynold’s number relationship for various spheres when the fluid viscosity is known.


Long Glass Tubes


Spherical Balls


Different Liquids


Triple Beam Balance


Stop Watch / Timer


Micrometer Caliper

Basic parts of a micrometer caliper

How to read a micrometer caliper.

Micrometer thimble reading 5.78mm

EXPERIMENTAL PROCEDURE p1

1. Fill the measuring with the different fluids (water, oil1 and oil2).

2. Record the height of the fluid, h, in meter.

3. Find the mass of the ball, m in kilogram using the triple beam balance weighing scale.

4. Measure the diameter of the spherical steel ball in meter using the micrometer caliper. Record the radius, r, also in meter.

EXPERIMENTAL PROCEDURE p2

5. Release the ball inside the long tube. Start the stop watch as the ball touches the surface of the fluid and stop at the end of the tube. Record the time, s, in seconds.

6. Calculate the velocity of the spherical steel ball (assume constant velocity).

7. Calculate the viscosity of the fluid using the derived equation from Stokes’ law. Take g = 9.8066 m/s2.

Experiment #3

Measurement Of Flowa. Flow at Venturi meter

b. Flow at the Orifice Plate

OBJECTIVES•To understand, measure and

compare the actual and expected volume flow rate of water through a VENTURI METER and of the ORIFICE meter.

•To plot CALIBRATION curve for the flow rate in the ROTAMETER.


Flow Measuring Apparatus

VENTURI METER

ORIFICE PLATE METER

ROTAMETER

DETAILS OF FLOW MEASURING APPARATUS

Fluid Lab Expt

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