3. An engine operating on the air standard heat engine, initially at 1.02 bar and 23 °C is compressed isentropic ally to 21 bar. Heated at Isopiestic process until the temperature is 940 °C; Expanded isentropic ally to its initial volume; finally cooled at Isochoric process to the initial pressure. Determine • The heat absorbed • The heat rejected • The ratios of the cycle The efficiency of the cycle

3. An engine operating on the air standard heat engine, initially at 1.02 bar and 23 °C is compressed isentropic ally to 21 bar. Heated at Isopiestic process until the temperature is 940 °C; Expanded isentropic ally to its initial volume; finally cooled at Isochoric process to the initial pressure. Determine • The heat absorbed • The heat rejected • The ratios of the cycle The efficiency of the cycle

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 12RQ: Refrigerators currently being manufactured in the United States are using______as their refrigerant.

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Air undergoes Isothermal expansion in a Carnot cycle where the pressure decreases from 2.5 MPa to 1.5 MPa. This process has a temperature of 550 K and it decreases to 400 K beforethe Isothermal compression stroke. Find a.) Qa, b.) Qr, c.) Wnet(kJ/kg),d.)the efficiency(%), e.) draw the T-S diagram with proper label of points, and f.) the pressuresbefore and after Isothermal compression
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A boiler takes in feed water at 70 °C and generates steam at a pressure of 10 bar and drynessfraction 0.92. The wet steam enters a superheater and emerges with the same pressure at atemperature of 400 °C. If the steam flow rate is 5 tonnes per hour, determine (i) the rate atwhich heat transfer takes place in the boiler and (ii) the rate at which heat transfer takes placein the superheater. State any assumptions you have made in relation to the steady flowequation for the process.
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Refrigerant 134a enters a refrigerator compressor as superheated vapor at 0.20 MPa and -5 ° C at a rate of 0.7 kg / s, and exits at 1.2 MPa and 70 ° C. The refrigerant is cooled in the condenser to 44 ° C and 1.15 MPa, and is throttled to 0.2 MPa. Neglecting any heat transfer and any pressure drop in the connecting lines between the components, show the cycle on a Ts and Ph diagram with respect to the saturation lines, and determine (a) the rate of heat removal from the refrigerated space and the power input to the compressor, b) the isentropic efficiency of the compressor, and c) the COP of the refrigerator
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A 14 x 12-in., single-cylinder, double-acting air compressor with 5.5% clearance operates at 12 rpm. The suction pressure and temperature are 14 psia and 100°F, respectively. The discharge pressure is 42 psia. Compression and expansion processes are polytropic, with n= 1.30. Determine (a) the volumetric efficiency, (b) mass and volume at suction conditions handled each minute, (c) the work, (d) the heat rejected, (e) the indicated air hp developed if the polytropic compression efficiency is 75%, and (f) the compression efficiency.
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