Semester 2 (2018) Page 1 of 19

ENS2160

Thermodynamics

Assignment / Part -1

PDF Release Date 22.08.2018

Due Date 02:00 PM, 06.09.2018

Late penalties will apply for any lodgement submitted after the

due date/time (5% per day or part thereof, with no marks

awarded after being late for 5 working days).

Lodgement Lodge in the Assignment box,

School of Engineering, Level 2, Reception

Please note the following:

(1) Attempt all parts.

(2) Submissions are to be lodged in hard copy (not via email).

(3) This assignment/part has multiple questions. This assignment part is worth 17.5

marks of the total unit score.

(4) All submissions must include a completed Assignment Cover Sheet. The cover sheet

is already included into this template. Do not remove it please.

(5) Write all formulae needed to arrive at solutions in the boxes provided. You should

practice on some scrap paper first and then transfer your “neat” solutions to this

template. The boxes given are adequately sized if you do this.

(6) All solutions must in neatly written text. Typed or photocopied solutions will not be

accepted.

(7) For additional information, refer to your lecturer.

You must keep copies of all work submitted as you see necessary.

This is an individual-based assessment. You may discuss the general

underlying theory and methods relevant to solving this assessment with

your peers… but … the final solution arrived to, the steps used to reach

the solution and submission made, must be solely based on your

intellectual output and is your responsibility.

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ASSIGNMENT COVER SHEET

Electronic or manual submission

UNIT

ENS2160 THERMODYNAMICS

CODE TITLE

NAME OF STUDENT

(Print clearly)

FAMILY NAME FIRST NAME

STUDENT ID

NO.

NAME OF LECTURER DR LEI SHI DUE DATE

Topic of assignment ASSIGNMENT PART-1

Group or tutorial (if applicable) Course Campus

I certify that the attached assignment is my own work and that any material drawn from other

sources has been acknowledged. This work has not previously been submitted for

assessment in any other unit or course.

Copyright in assignments remains my property. I grant permission to the University to make

copies of assignments for assessment, review and/or record keeping purposes. I note that

the University reserves the right to check my assignment for plagiarism. Should the

reproduction of all or part of an assignment be required by the University for any purpose

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relevant form.

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this form, filled it in completely and that you certify as above.

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OR, if submitting this paper electronically as per instructions for the unit, place an ‘X’ in the box below to

indicate that you have read this form and filled it in completely and that you certify as above. Please

include this page in/with your submission. Any electronic responses to this submission will be sent to

your ECU email address.

Agreement Date

You must complete the above form or the work will not be assessed

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Question 1 10 % Max Problem Statement

A gasoline line is connected to a pressure gage through a double-U manometer

(as shown in figure below), and the reading of the pressure gage is 370 kPa.

(Figure P2-78. Cengel, Y. A., Cimbala, J. M. & Turner, R. H. (2017). Fundamentals of thermal-fluid sciences

(5th ed). New York: McGraw-Hill Companies, Inc.)

Your task is to determine:

The gage pressure of the gasoline line.

*Note *

If property data are extracted from tables in your solution, clearly identify these

data and the tables they are extracted from.

… test paper continued

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Question 1 Working Space

… test paper continued

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Question 2 10 % Max Problem Statement

Water is pumped from a lake to a storage tank 15 m above at a rate of 70 L/s

while consuming 15.4 kW of electric power (disregarding any frictional losses in

the pipes and any changes in kinetic energy).

(Figure P3-61. Cengel, Y. A., Cimbala, J. M. & Turner, R. H. (2017). Fundamentals of thermal-fluid sciences

(5th ed). New York: McGraw-Hill Companies, Inc.)

Your task is to determine:

(2-A). The overall efficiency of the pump–motor unit. [5% Max]

(2-B). The pressure difference between the inlet and the exit of the pump. [5%

Max]

*Note *

If property data are extracted from tables in your solution, clearly identify these

data and the tables they are extracted from.

… test paper continued

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Question 2 Working Space

… test paper continued

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Question 3 20 % Max Problem Statement

Complete this table for H2O:

T, °C P, kPa h, kJ / kg x Phase description

200 0.7

140 1800

950 0.0

80 500

800 3162.2

*Note *

If property data are extracted from tables in your solution, clearly identify these

data and the tables they are extracted from.

… test paper continued

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Question 3 Working Space

… test paper continued

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Question 4 15 % Max Problem Statement

A rigid tank initially contains 1.4-kg saturated liquid water at 200°C. At this state,

25 percent of the volume is occupied by water and the rest by air. Now, heat is

supplied to the water until the tank contains saturated vapor only.

(Figure P4-57. Cengel, Y. A., Cimbala, J. M. & Turner, R. H. (2017). Fundamentals of thermal-fluid sciences

(5th ed). New York: McGraw-Hill Companies, Inc.)

Your task is to determine:

(4-A). The volume of the tank. [5% Max]

(4-B). The final temperature and pressure. [5% Max]

(4-C). The internal energy change of the water. [5% Max]

*Note *

If property data are extracted from tables in your solution, clearly identify these

data and the tables they are extracted from.

… test paper continued

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Question 4 Working Space

… test paper continued

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Question 5 15 % Max Problem Statement

An insulated rigid tank initially contains 1.4-kg saturated liquid water at 200°C

and air. At this state, 25 percent of the volume is occupied by liquid water and

the rest by air. Now, an electric resistor placed in the tank is turned on, and the

tank is observed to contain saturated water vapor after 20 min.

(Figure P5-102. Cengel, Y. A., Cimbala, J. M. & Turner, R. H. (2017). Fundamentals of thermal-fluid

sciences (5th ed). New York: McGraw-Hill Companies, Inc.)

Your task is to determine:

(5-A). The volume of the tank. [5% Max]

(5-B). The final temperature. [5% Max]

(5-C). The electric power rating of the resistor (Neglect energy added to the

air). [5% Max]

*Note *

If property data are extracted from tables in your solution, clearly identify these

data and the tables they are extracted from.

… test paper continued

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Question 5 Working Space

… test paper continued

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Question 6 15 % Max Problem Statement

Refrigerant-134a at 1 MPa and 90°C is to be cooled to 1 MPa and 30°C in a

condenser by air. The air enters at 100 kPa and 27°C with a volume flow rate of

600 m3

/min and leaves at 95 kPa and 60°C.

(Figure P6-69. Cengel, Y. A., Cimbala, J. M. & Turner, R. H. (2017). Fundamentals of thermal-fluid sciences

(5th ed). New York: McGraw-Hill Companies, Inc.)

Your task is to determine:

The mass flow rate of the refrigerant.

*Note *

If property data are extracted from tables in your solution, clearly identify these

data and the tables they are extracted from.

… test paper continued

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Question 6 Working Space

… test paper continued

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Question 7 15 % Max Problem Statement

Carbon dioxide enters an adiabatic compressor at 100 kPa and 300 K at a rate

of 0.5 kg/s and leaves at 600 kPa and 450 K (Neglecting kinetic energy changes).

Your task is to determine:

(7-A). The volume flow rate of the carbon dioxide at the compressor inlet. [7%

Max]

(7-B). The power input to the compressor. [8% Max]

*Note *

If property data are extracted from tables in your solution, clearly identify these

data and the tables they are extracted from.

… test paper continued

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Question 7 Working Space

… test paper continued

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Additional Working Space

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Additional Working Space

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Additional Working Space

3

END OF ASSIGNMENT

You will only be graded against the individual questions if you provide

the necessary hand-written solutions via this Assignment Template.

Any questions that do not have a written solution in this Assignment

Template will be graded as zero for those questions.