a) Explanation Write the expression to calculate the entropy change during the process 3-4. s 4 − s 3 = − − q o u t , 34 T 0 (I) s 4 − s 3 = c p ln T 4 T 3 − R ln P 4 P 3 Here, in process 3-4 temperature T 4 and T 3 are equal. s 4 − s 3 = c p ln T 4 T 3 ↵ 0 − R ln P 4 P 3 = − R ln P 4 P 3 (II) Here, heat output during the process 3-4 is q o u t , 34 , surrounding temperature is T 0 , temperature at state 4 is T 4 , temperature at state 3 is T 3 , pressure at state 3 is P 3 , pressure at state 4 is P 4 , gas constant is R and the specific heat of air at constant pressure is c p . Conclusion: Substitute 150 kJ / kg for q o u t and 27 ° C for T L in Equation (I) b) To determine The net work output per unit mass of air. c) To determine The thermal efficiency of the cycle

8th Edition

ISBN: 9780100257054

Author: CENGEL

Publisher: YUZU

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Question

Chapter 9.12, Problem 71P

To determine

The maximum pressure in the cycle.

To determine

The net work output per unit mass of air.

To determine

The thermal efficiency of the cycle

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Chapter 9.12, Problem 70P

Chapter 9.12, Problem 72P

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Chapter 9 Solutions

EBK THERMODYNAMICS: AN ENGINEERING APPR

Ch. 9.12 - What are the air-standard assumptions?Ch. 9.12 - What is the difference between air-standard...Ch. 9.12 - How does the thermal efficiency of an ideal cycle,...Ch. 9.12 - What does the area enclosed by the cycle represent...Ch. 9.12 - Prob. 5P Ch. 9.12 - Prob. 6P Ch. 9.12 - Can the mean effective pressure of an automobile...Ch. 9.12 - Prob. 8P Ch. 9.12 - What is the difference between spark-ignition and...Ch. 9.12 - Prob. 10P

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