lab manual thermofluid

1

UNIVERSITI TEKNOLOGI MARA

FACULTY OF CHEMICAL ENGINEERING

THERMOFLUID

LABORATORY

CGE 536

2

Thermofluid Laboratory

Reporting of Practical Work

1. Raw Data

Students must submit to the instructor/lecturer their raw data, graph or drawing at the end of

each experiment. Raw data should be a table containing all the measurements performed

according to instructions, written on an A4 paper. Particulars such as below should be

included:

Name of experiment

Name of present students in the group

Date experiment performed

A short comment is expected on whether the results substantiated the theory and factors

which contribute to discrepancies. A full report must be submitted within two weeks after

the completion of the experiment.

2. Full Report

The general order of the various sections of a full Iaboratory report is set out below:

Front cover

Table of content

Abstract / Summary

Introduction

Aims / Objectives

Theory

Procedures

Apparatus

Results

Sample Calculations

Sample of calculation of errors (if necessary)

Discussions

Conclusions

Recommendation

References

Appendices

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3. Summary

The summary is important because it provides information to persons not wanting to read

the whole report. The summary should also contain the general conclusions of any

experimental work under the test conditions and recommendations, (if any). It should not

discuss the reasoning or detailed evidence that is contained in the body of the report. Most

important, the summary must be brief.

4. Equipment description and experimental technique

Enough should be said of the equipment and technique so that the reader could operate the

equipment if necessary.

5. Calculated results

A summary of the calculated results should be clearly tabulated. Related variables should be

presented graphically where dependence need to be shown.

6. Sample of calculation

A sample of calculation from a set of raw date obtained must be presented in the report

using all formulae used in obtaining the final calculated result.

7. Calculation of errors

It is important to show the calculation of errors as the reader will know how efficient the

experiment has been carried out. The experimental error calculation can be carried out by

comparing it with the expected theoretical values.

8. Discussion

In this section, the results of the experiments are presented as a fulfillment of the aim. It is a

coordinated analysis of what the data and calculated results mean. From the analysis, should

come the overall impression of the meaning of the experiment and its significance in the

light of published work or established theory.

The material should be presented logically. Even the most complicated explanation or theory

can be conveyed easily to the reader if broken down and presented in logical sequence. If the

discussion is long, its organization should be facilitated by the use of subdivisions and

headings.

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“Summary” but will be more detailed in that it will include the opinion reasoning of the

author about various aspects of the experiment. The limitation of the experiment must be

discussed and the accuracy of the results noted.

This section must show the significance of the experimental findings has been appreciated.

Recommended journals, textbooks or lecture notes will provide an aid to such an

understanding.

9. Conclusions

The analysis must be objective, keeping in mind experimental problems or deviations from

conditions reported in published work and making a conclusion, if possible, in the light of

this.

10. Recommendations

The recommendations could indicate how the experimental technique or apparatus should be

improved, considering what conclusions were arrived at and what consistency with

expected performance the experimental results showed. It is also wise to include the

observations that cause errors occurred during the experiment.

11. References

Reference provides the reader with sources of information that were used during the writing

of the experimental report. Thus reported data or formulae checked for validity etc.

Book and journal references must follow a standard format that includes the author, title,

journal, volume, pages, date and publisher.

12. Appendices

Appendices contain material that is not an integral part of the report or cannot be included

conveniently in the body of the report.

These should include material such as supporting information, mathematical derivations,

answers to question included on the typed experimental sheet or similar material that would

overload the body of the report without contributing significantly to the immediate line of

thought.

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UNIVERSITI TEKNOLOGI MARA

FAKULTI KEJURUTERAAN KIMIA

THERMOFLUID LABORATORY

(CGE 536)

NAME :

STUDENT NO :

EXPERIMENT :

DATE PERFORMED :

SEMESTER :

PROGRAMME/ CODE :

GROUP :

No Title Allocated Marks % Marks

1 Abstract/ Summary 5

2 Introduction 5

3 Aims/ Objectives 5

4 Theory 5

5 Apparatus 5

6 Procedure 10

7 Result 10

8 Calculations 10

9 Discussion 20

10 Conclusions 10

11 Recommendations 5

12 References 5

13 Appendices 5

TOTAL 100

Remarks:

Checked by:

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LABORATORY SAFETY AND REGULATIONS

A. General Laboratory Rules.

1. Always wear the lab coat before performing any experiments and a suitable

protective gear to ensure your safety in the laboratory. Students are not allowed

to perform the experiments without wearing the lab coat.

2. Always wear appropriate shoes, never wear sandals or shorts, exposure of legs

and feet to spilled chemical is the main cause of chemical burns.

3. Do not eat, smoke or chew gum or tobacco in the laboratory or chemical storage

areas. Do not use laboratory glassware for food or beverages, including the

refrigerators.

4. Never work alone in the chemical laboratory and storage area.

5. Do not fool around in the laboratory. Horseplay and pranks can be dangerous.

6. Students are not allowed to use hand phones in the laboratory.

7. Observe good housekeeping in the laboratory.

8. Never pipette with your mouth.

9. Report any accident or near miss to the lab technician (e.g. broken glassware or

equipment, any fire or chemical spillage).

10. Always wash your hands before and after working in the laboratory, and also

after cleanup of spillage.

11. Never leave heat sources unattended (eg. Gas burners. hot plates, heating

mantles, sand baths, etc.)

12. Never lean into fume hood.

13. Do not perform unauthorized experiments.

14. Read all procedures and anticipate for possible hazards.

15. In case of any emergency please call these numbers for help: 03-55436303/6304

(FKK General Office)

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B. Lab Attendance

Attendance to the lab is compulsory to each student and for all lab sessions. Students who do

not attend any of the lab sessions without a valid reason will not be allowed to do

replacement labs. In other words, the submission of lab report will not be allowed without

the attendance to the lab. Students who are late for more than 15 minutes will not be

allowed to perform the experiments.

C. Experimental Data

Students must verify the experimental data with the respective lecturer at the end of every

experiment. The experimental data sheet must be signed by the respective lecturer before

leaving the lab session.

D. Submission of Lab Reports

The lab reports should be submitted within two weeks after the date of conducted

experiments to the respective lecturer. Marks will be penalized for late submission.

Individual evaluation will be done on each student.

Please identify your group’s lecturer. Submission of lab report to the wrong lecturer will

affect your grade. Lecturers will not be responsible for missing lab reports by the students.

DO NOT submit the lab reports to the FKK general office/ Technician Office

DO NOT submit the lab reports in the lecturer’s pigeon holes in the FKK general office.

Students shall submit the lab reports directly to the lecturer during the following lab session

or in the respective lecturer’s office. To avoid missing lab reports, always discuss with your

lecturer the best place to hand over the lab reports.

E. Plagiarism

Plagiarism is totally not allowed in lab reports. Students who are caught cheating or who

plagiarized the lab reports will be penalized without any notice or warning.

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G. Open Ended & Closed Ended

For Open Ended experiment, students are required to construct a procedure for a given

experiment and do the consultation with the respective lecturer before running the

experiment. Laboratory report for Open Ended experiment should be done in group. For

Closed Ended Experiment, students are required to conduct experiment based on the

standard operating procedure that has been given in the manual. Individual laboratory report

must be submitted for for Closed Ended experiment.

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LAB 1: Flow over Weirs (Open-Ended)

Investigations of weir flows aim at studying the relation between the discharge coefficient and the parameters influencing the flow. Weirs are hydraulic structures consisting of an obstruction placed across a water channel with a specially shaped opening or notch. The weir structure will increase the water level, which will be measured. Water level-discharge relationships are available for standard-shaped openings or notches. Two types of weirs are widely used such as Rectangular Shape Opening and (V) Notch in experiment of flow over weirs. Stilling baffle is used to ensure minimum turbulence. The stilling baffle will act as a reservoir to collect water volume and slowly disperse the water from the opening at the bottom of the stilling baffle. Rectangular Weir: The rectangular weir is able to measure higher flows than the v-notch weir and over a wider operating range.

Figure 1: Rectangular Weir

V-Notch: The V-notch weir is a notch with a V shape opening. V-notch weir typically used to measure low flows within a narrow operating range.

Figure 2: V-Notch

Based on the theory above, you are required to construct a lab procedure to evaluate the flow characteristics demonstration over a rectangular notch and a (V) notch. In addition, the discharge coefficients for both weirs must be determined.

90°

50mm

B, 30mm

89mm

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LAB 2: Flowmeter Demonstration (Open- Ended)

a) Rotameter The rotameter is a flow meter in which a rotating free float is the indicating element. Basically, a rotameter consists of a transparent tapered vertical tube through which fluid flow upward. Within the tube is placed a freely suspended “float” of pump-bob shape. When there is no flow, the float rests on a stop at the bottom end. As flow commences, the float rises until upward and buoyancy forces on it are balanced by its weight. The float rises only a short distance if the rate of flow is small, and vice versa. The points of equilibrium can be noted as a function of flow rate. With a well-calibrated marked glass tube, the level of the float becomes a direct measure of flow rate.

Figure 3: The Rotameter b) Venturi Meter The venturi meter consists of a venturi tube and a suitable differential pressure gauge. The venturi tube has a converging portion, a throat and a diverging portion as shown in the figure below. The function of the converging portion is to increase the velocity of the fluid and lower its static pressure. A pressure difference between inlet and throat is thus developed, which pressure difference is correlated with the rate of discharge. The diverging cone serves to change the area of the stream back to the entrance area and convert velocity head into pressure head.

Figure 4: Venturi Meter

Tapered tube

Flow

Scale

1 2

Inlet

Throat

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c) Orifice Meter The orifice for use as a metering device in a pipeline consists of a concentric square-edged circular hole in a thin plate, which is clamped between the flanges of the pipe as shown in the figure below.

Figure 5: Orifice Meter Pressure connections for attaching separate pressure gauges are made at holes in the pipe walls on both side of the orifice plate. The downstream pressure tap is placed at the minimum pressure position, which is assumed to be at the vena contracta. The centre of the inlet pressure tap is located between one-half and two pipe diameters from the upstream side of the orifice plate, usually a distance of one pipe diameter is employed. Based on the theory above, you are required to construct a lab procedure for general start up and a procedure to determine the flow rate for three basic types of flow measuring techniques such as rotameter, venturi meter and orifice meter. You can use Bernoulli Equation to calculate the flowrate measurement for venturi meter and orifice meter.

A1

A2

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LAB 3: Fluid Mixing (Open-Ended)

Mixing of liquid liquid or solid liquid systems is a complex operation to analyse and subject to many variables. The choice of mixer for a particular application depends on the degree of bulk movement or shear mixing required by the process. In order to predict full scale requirements it is usual to model the system and apply dimensional analysis. Before the dimensional analysis can be used three conditions must apply:

Geometric Similarity - This will define the boundary conditions; corresponding dimensions

will have the same ratio.

Kinematic Similarity - This requires that velocities at corresponding points must have the

same ratio as those at other corresponding points.

Dynamic Similarity - This requires that the ratio of forces at corresponding points is equal to

that at other corresponding points.

Two modes of flow behaviour exist in a mixer: laminar and turbulent flow. Both these flow conditions may be described dimensionally but for turbulent flow its behaviour is less significant. In particular the Power number becomes independent of Reynolds’ number beyond a certain turbulence range. A further factor to consider is surface waves which are described by the Froude number group. In a mixer this phenomena is usually a function of the height of the vortex which forms. Based on the theory above, you are required to construct a lab procedure in order to achieve the following objectives;

1. To observe the various flow patterns that can be achieved by the use of different impellers with and without the use of baffles.

2. To show how the power consumed by a mixer varies with speed, type of impeller, and with the inclusion of baffles.

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LAB 4: Free and Force Vortex (Open-Ended)

a) Free Cylindrical Vortex

When a liquid is flowing out of a tank through a hole at the bottom of the tank, free vortex is formed with the number of oscillation depending on the distortion that created the flow. The liquid is moving spirally towards center following current, energy per unit mass is assumed to be constant when energy loss by viscosity is neglected. If, while the mass of water is rotating, the central exit hole is plugged, the flow of water in the vertical plane ceases and the motion becomes one of simple rotation in the horizontal plane. This is known as free cylindrical vortex. Bernoulli’s theorem can be used because the movement is along the flow axis,

zg

V

g

p

2

2

Constant

For horizontal plane, the relation becomes

g

V

g

p

2

2

Constant

Integration of the above relation with r gives

01

dr

dV

g

V

dr

dp

g (1)

Next, consider a pair of stream line being divided with distance r and is in same horizontal plane and

are linked by a fluid tube wide A . The centrifugal force of the tube is balanced by the pressure difference between both ends, that is

Ardr

dp

gr

VrAg

2

dr

dp

gr

gV

2 (2)

Combine (1) and (2) to produce

02

dr

dV

g

V

gr

V

0r

V

dr

dV

Integrate above relation to obtain

Vr lnln Constant

Kvr (Constant)

r

KV (3)

In free cylinder vortex, velocity is inversely proportional to distance from spiral axis. Bernoulli’s theorem is used to determine surface profile as follow:

Czg

V

2

2

(Constant) (4)

Substitute (3) into (4)

Czgr

K

2

2

2

14

2

2

2gr

KzC (5)

That is, equation for hyperbolic curve Ayx 2 that is symmetry to axis of rotation and is horizontal to

z = C

b) Free Vortex Movement in free vortex is different with free cylindrical vortex because free vortex contains radial velocity towards center. Equation for such situation can be generated by considering the water passes through round segments towards its diameter, where energy passing any tube and is kept constant until

zg

V

g

p

2

2

Constant

If A and V is surface area and velocity of a particular position while 1A and 1V are surface area and

velocity at distance r from center circle,

11VAAV Constant

By taking KrA ,

r

VrV 11

If z is constant,

Cgr

Vr

g

p

2

2

1

2

1

2

2

2

1

2

1

2gr

VrC

g

p

(6)

Also,

Cg

V

g

p

2

2

11

2

2

1

2

1

2

11

22 gr

Vr

g

V

g

pp

2

2

1

2

11 12 r

r

g

V

g

pp

(7)

Free vortex can be said as combination of cylinder vortex and radial flow. Velocity is inversely proportional to radius in every case. Angle between flow axis and radius vector at any point is constant and these axis form the spiral pattern.

c) Forced Vortex

As we know, angular velocity is constant,

rV Increase in radial pressure is given by

rr

V

dr

dp 22

15

2

1

2

1

2p

p

r

r

rdrdp

)(2

1 2

1

2

2

2

12 rrpp (8)

By taking 01 pp , when 01 r , and pp 2 when rr 2 ,

22

0

2r

g

w

g

pp

Because hg

p

, so

22

2r

ghh o

22

02

rg

hh

(9)

This is a parabolic equation. Surface profile for forced vortex can be represented by equation:

g

rz

2

22

Distribution of total head can be represented by equation:

g

rH

22

Where: Z = Surface profile = Angular velocity r = Radius g = Gravity H = Total Head

Angular velocity can be calculated by:

Where:

Z = Surface profile Ω = Angular velocity r = Radius g = Gravity

Based on the theory above, you are required to construct a lab procedure in order to achieve the following objectives;

1. To study on surface profile and speed for free and forced vortex. 2. To find a relation between surface profile and speed for free and forced vortex.

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LAB 5: Film Boiling Condensation (Close-Ended)

The use of steam both for power production to convey heat has a long history and its use in these fields is likely to continue into the foreseeable future.

In all applications, the steam must be condensed as it transfers heat to a cooling medium which could be cold water in a condenser of generating station, hot water in a heating calorifier, sugar solution in a sugar refinery and etc. During condensation very high heat fluxes are possible and provided that the heat can be quickly transferred from the condensing surface into the cooling medium, the heat exchangers can be compact and effective.

Steam may condense onto a surface in two distinct modes, known as the Filmwise and the Dropwise condensation. For the same temperature difference between the steam and the surface, dropwise condensation is several times more effective than filmwise, and for this reason the former is desirable although in practical plants, it seldom occurs for prolonged periods.

The SOLTEQ® Film & Dropwise Condensation Unit (Model: HE163) is designed to help student to understand several key aspects in condensation topic, in particular the process of filmwise and dropwise condensation. It allows students to visualize both phenomena and perform a few experiments to demonstrate both concepts. GENERAL OPERATING PROCEDURES Temperature Reading To read a particular temperature, use the temperature selector knob to select the desired reading. The knob indicates temperature T1 to T4. Tsurf of filmwise and Tsurf of dropwise are indicated by individual digital displays. Cooling Water Flow Reading To read a particular flow, use the flow selector knob to select the desired reading (FT1 or FT2). Heater Setting To turn on the heater, turn the heater switch to “ON” position. The power supply to the heater is controlled by turning the potentiometer clockwise to increase the value or anticlockwise to reduce the value. Use both coarse and fine regulators to obtain the desired heating power. Cooling Water Control The cooling water flowrate can be controlled by simply turning the valve clockwise to reduce flow rate or turning the valve anti-clockwise to increase flow rate.

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EXPERIMENTAL PROCEDURE General Start-up Procedures

1. Ensure that the main switch is in the off position. 2. Turn the power regulator knobs fully anti-clockwise to set the power to minimum. 3. Check to ensure that valves V1 to V6 are closed. 4. Fill the chamber with distilled water until the water level stays between the heater

and baffle plates. Always make sure that the heater is fully immersed in the water throughout the experiment. Water could be filled into the chamber through the drain valve with the vent valve, V4 opened. Then close the vent valve, V4.

5. Adjust the water flow rate to the condenser by controlling the control valve according to the experimental procedure.

6. Turn on the main switch and the heater switch. Set the heater power by rotating the power regulator clockwise to increase the heating power.

7. Observe the water temperature reading; it should increase when the water starts to heat-up.

8. Heat up the water to boiling point until the pressure reaches 1.02 – 1.10 bar. Immediately open valve V1 and follow by valve V5 for 1 minute to vacuum out the air inside the condenser. Then close both valves V1 and V5.

9. Let the system to stabilize. Then take all relevant measurements for experimental purposes. Make adjustment if required.

General Shut-down Procedures

1. Turn the voltage control knob to 0 Volt position by turning the knob fully anti-clockwise. Keep the cooling water flowing for at least 5 minutes through the condensers to cold them down.

2. Switch off the main switch and power supply. Then, unplug the power supply cable.

3. Close the water supply and disconnect the cooling water connection tubes if necessary. Otherwise, leave the connection tubes for next experiment.

4. Discharge the water inside the chamber using the discharge valve.

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Experiment 1: DEMONSTRATION OF FILMWISE AND DROPWISE CONDENSATION Objective: To demonstrate the filmwise and dropwise condensation

Procedures: Follow the basic procedure as written in general start-up and shut down procedures. Make sure that the equipment is connected to the service unit. Assignment: Describe the characteristics of filmwise and dropwise condensation and how it may affect the efficiency of the condensers.

Experiment 2: THE FILMWISE HEAT FLUX AND SURFACE HEAT TRANSFER COEFFICIENT DETERMINATION AT CONSTANT PRESSURE Objective: To determine the filmwise heat flux and surface heat transfer coefficient at constant pressure

Procedures:

1. Circulate cooling water through the filmwise condenser starting with a minimum value of 0.1 LPM.

2. Adjust the heater power to obtain the desired pressure at 1.01 bar. 3. When the condition is stabilized, record the steam (Tsat) & surface temperature

(Tsurf), Tin (T1) & Tout (T2), and flowrate.

Assignment: 1. Plot Heat Flux vs. Temperature Difference (Tsat - Tsurf). 2. Plot a Surface Heat Transfer Coefficient vs. Temperature Difference (Tsat -Tsurf).

Note: Power is calculated using the heat removed from the cooling water

( ).

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Experiment 3: THE DROPWISE HEAT FLUX AND SURFACE HEAT TRANSFER COEFFICIENT DETERMINATION AT CONSTANT PRESSURE Objective: To determine the dropwise heat flux and surface heat transfer coefficient at constant pressure

Procedures:

1. Circulate cooling water through the dropwise condenser starting with a minimum value of 0.4 LPM.

2. Adjust the heater power to obtain the desired pressure at 1.01 bar. 3. When the condition is stabilized, record the steam ((Tsat) & surface temperature

(Tsurf), Tin (T3) & Tout (T4), and flowrate.

Assignment: 1. Plot Heat Flux vs. Temperature Difference (Tsat - Tsurf). 2. Plot Surface Heat Transfer Coefficient vs. Temperature Difference (Tsat -Tsurf). 3. Plot Heat Flux vs. Temperature Difference (Tsat - Tsurf) for filmwise and dropwise

condensation in a single graph. Plot also Surface Heat Transfer Coefficient vs. Temperature Difference (Tsat -Tsurf) for filmwise and dropwise condensation in a single graph. Compare and discuss the heat transfer coefficients between filmwise and dropwise condensation.

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Experiment 4: THE EFFECT OF AIR INSIDE CHAMBER Objective:

To demonstrate the effect of air on heat transfer coefficient of condensation.

Procedures: 1. Circulate cooling water through the filmwise condenser at the highest flowrate

until the pressure is reduced to below 1 bar. 2. Open the discharge valve and let an amount of air to enter the chamber.

Note: Increase of 0.01 bar indicates 1% of air is injected. 4. Regulate the water flow rate to the condenser starting with a minimum value of

0.4 LPM. 5. Adjust the heater power to obtain the desired pressure at 1.01 bar. 6. When the condition is stabilized, record the steam (Tsat) & surface temperature

(Tsurf), Tin (T3) & Tout (T4), and flowrate. 7. Repeat step 1-6 for dropwise condensation.

Assignment:

1. Plot Surface Heat Transfer Coefficient vs. Temperature Difference (Tsat - Tsurf) with the presence of air, for filmwise and dropwise condensation respectively.

2. Plot Surface Heat Transfer Coefficient vs. Temperature Difference (Tsat - Tsurf) with the presence of air and without presence of air in a single graph, for filmwise and dropwise condensation respectively. Compare and discuss the effect of air on heat transfer coefficients.

3. Describe the phenomena theoretically.

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EQUIPMENT MAINTENANCE

1.1 Heater Cool down the equipment before draining the water inside the glass vessel so that the heater will not be overheated when there is no water inside the vessel.

1.2 Condenser

Make sure tap water used is free from any contamination to prevent blockage inside the condenser.

SAFETY PRECAUTION

1.3 Warning

High voltages exist and are accessible in the control panel. Return the unit to your supplier for any servicing.

1.4 Cautions

1. Never splash water to the control panel. This will cause body injury and damage to the equipment.

2. Never use your bare hand to test the AC Power Supply. It may cause hazardous injury.

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LAB 6: Properties Measurement/PVT (Close-Ended) The Perfect Gas Law Apparatus is customarily designed and developed to provide students a comprehensive understanding of First Law of Thermodynamics, Second Law of Thermodynamics and relationship between P-V-T. The Perfect Gas Expansion Apparatus enable the students to have a good understanding in energy conservation law and the direction in which the processes proceed.

The Perfect Gas Expansion Apparatus comes with one pressure vessel and one vacuum vessel. Both vessels are made of glass tube. The vessels are interconnected with a set of piping and valves. A large diameter pipe provides gradual or instant change. Air pump is provided to pressurize or evacuate air inside the vessels with the valves configured appropriately. The pressure and temperature inside the vessels are monitored with pressure and temperature sensors and clearly displayed by digital indicator on the control panel. With an optional automatic data acquisition system, the modern version of a classic Clement and Desormes experiment can be conducted as pressure and temperature changes can be monitored continuously with the computer. EXPERIMENTAL PROCEDURES General Operating Procedures General Start-up Procedures

1. Connect the equipment to single phase power supply and then switch on the unit. 2. Fully open all valves and check the pressure reading on the panel. This is to make

sure that the chambers are under atmospheric pressure. 3. Then, close all the valves. 4. Connect the pipe from compressive port of the pump to pressurized chamber or

connect the pipe from vacuum port of the pump to vacuum chamber. 5. Now, the unit is ready for use.

General Shut-down Procedures 1. Switch off the pump and remove both pipes from the chambers. 2. Fully open the valves to release the air inside the chambers. 3. Switch off the main switch and power supply.

23

Experiment 1: Boyle’s Law Experiment Objectives:

To determine the relationship between pressure and volume of an ideal gas

To compare the experimental results with theoretical results

PRECAUTIONS:

When carrying out the experiment, pump pressure level should not exceed 2 bar as excessive pressure may result in glass cylinder breaking.

Experimental Procedures:

1. Perform the general start up procedures in section 5.1. Make sure all valves are fully closed.

2. Switch on the compressive pump and allow the pressure inside chamber to increase up to about 150kPa. Then, switch off the pump and remove the hose from the chamber.

3. Monitor the pressure reading inside the chamber until it stabilizes. 4. Record the pressure reading for both chambers before expansion. 5. Fully open V 02 and allow the pressurized air flows into the atmospheric chamber. 6. Record the pressure reading for both chambers after expansion. 7. The experimental procedures can be repeated for the following conditions: a) From atmospheric chamber to vacuum chamber b) From pressurized chamber to vacuum chamber 8. Calculate the PV value and prove the Boyles’ Law.

Experiment 2: Gay-Lussac Law Experiment Objectives:

To determine the relationship between pressure and temperature of an ideal gas

Experimental procedures: 1. Perform the general start up procedures in section 5.1. Make sure all valves are fully

closed. 2. Connect the hose from compressive pump to pressurized chamber. 3. Switch on the compressive pump and records the temperature for every increment of

10kPa in the chamber. Stop the pump when the pressure PT 1 reaches about 160kPa. 4. Then, slightly open valve V 01 and allow the pressurized air to flow out. Records the

temperature reading for every decrement of 10kPa. 5. Stop the experiment when the pressure reaches atmospheric pressure. 6. The experiment is repeated for three times to get the average value. 7. Plot graph of pressure versus temperature.

24

Experiment 3: Isentropic Expansion Process Objectives:

To demonstrate the isentropic expansion process


closed. 2. Connect the hose from compressive pump to pressurized chamber. 3. Switch on the compressive pump and allow the pressure inside chamber to increase

until about 160kPa. Then, switch off the pump and remove the hose from the chamber. 4. Monitor the pressure reading inside the chamber until it stabilizes. Record the pressure

reading PT 1 and temperature TT 1. 5. Then, slightly open valve V 01 and allow the air flow out slowly until it reaches

atmospheric pressure. 6. Record the pressure reading and temperature reading after the expansion process. 7. Discuss the isentropic expansion process.

Experiment 4: Stepwise Depressurization Objectives:

To study the response of the pressurized vessel following stepwise depressurization




reading PT 1. 5. Fully open valve V 01 and bring it back to the closed position instantly. Monitor and

records the pressure reading PT 1 until it becomes stable. 6. Repeat step 5 for at least four times. 7. Display the pressure reading on a graph and discuss about it.

25

Experiment 5: Brief Depressurization Objectives:

To study the response of the pressurized vessel following a brief depressurization




reading PT 1. 5. Fully open valve V 01 and bring it back to the closed position after few seconds.

Monitor and records the pressure reading PT 1 until it becomes stable. 6. Display the pressure reading on a graph and discuss about it.

Experiment 6: Determination of ratio of volume Objectives:

To determine the ratio of volume and compares it to the theoretical value

Experimental Procedures:


2. Switch on the compressive pump and allow the pressure inside chamber to increase up to about 150kPa. Then, switch off the pump and remove the hose from the chamber.

3. Monitor the pressure reading inside the chamber until it stabilizes.

4. Record the pressure reading for both chambers before expansion.

5. Open V 02 and allow the pressurized air flows into the atmospheric chamber slowly.

6. Record the pressure reading for both chambers after expansion.

7. The experimental procedures can be repeated for the following conditions:

26

a) From atmospheric chamber to vacuum chamber

b) From pressurized chamber to vacuum chamber

8. Calculate the ratio of volume and compares it with the theoretical value.

Experiment 7: Determination of ratio of heat capacity

Objectives:

To determine the ratio of heat capacity

Experimental procedures:


2. Connect the hose from compressive pump to pressurized chamber. 3. Switch on the compressive pump and allow the pressure inside chamber to increase


reading PT 1 and temperature TT 1. 5. Fully open valve V 01 and bring it back to the closed position after few seconds.

Monitor and records the pressure reading PT 1 and TT1 until it becomes stable. 6. Determine the ratio of heat capacity and compare with the theoretical value.

lab manual thermofluid

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