Question 2 (a) For a gas turbine power cycle operating on an air-standard cycle, and treating the air as a perfect gas, show that the efficiency of the cycle is given by 1 Y-1 γ n = 1- \Rp/ where Rp is the pressure ratio. Also, show that the work ratio is given by Rw = 1 - TL (Rp) Y TH where TH and T are the highest and lowest temperatures in the cycle. (b) A gas turbine power plant operates on an air-standard Joule (Brayton) cycle with a pressure ratio of 7. The air enters the compressor at 25 °C and exits the combustion chamber at 700 °C. Taking Cp for air as 1.005 kJ kg¯¹K and y = 1.4, calculate (i) The efficiency (ii) The net specific work out (iii) The work ratio for the cycle, R₁ = 7.

Question 2 (a) For a gas turbine power cycle operating on an air-standard cycle, and treating the air as a perfect gas, show that the efficiency of the cycle is given by 1 Y-1 γ n = 1- \Rp/ where Rp is the pressure ratio. Also, show that the work ratio is given by Rw = 1 - TL (Rp) Y TH where TH and T are the highest and lowest temperatures in the cycle. (b) A gas turbine power plant operates on an air-standard Joule (Brayton) cycle with a pressure ratio of 7. The air enters the compressor at 25 °C and exits the combustion chamber at 700 °C. Taking Cp for air as 1.005 kJ kg¯¹K and y = 1.4, calculate (i) The efficiency (ii) The net specific work out (iii) The work ratio for the cycle, R₁ = 7.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 20RQ: Welded ______sealed compressors are normally used in household refrigerators.

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