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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questão1. Refrigerator 1 simulates an ideal refrigerator and therefore operates on a Carnot cycle using R-134a as the refrigerant at a flow rate of 1.4 kg/sec. The condensing and evaporating temperatures are 30 °C and -10 °C, respectively. To assess the performance of Refrigerator 1, you must submit the report. of the project with the following information: Enthalpies corresponding to the states indicated in the cycle (1, 2, 3 and 4); 1.a. The cooling rate (QL); 1.b. The work provided to the fluid by the compressor; 1.c. The work generated by the turbine; 1.d. The condenser heat rejection rate (QH); 1e. The coefficient of performance of the cycle;
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103#1. the working substance for a Carnot cycle is 8lbm of air. the volume at the beginning of isothermal expansion is 9cu ft and the pressure is 300 psia. the ratio of expansion during addition of heat is 2 and the temperature of the cold body is 90degree F. find (a)QA, (b) QR, (c) V3, (D)p3 ,(e) V4, (f) p4, (g) pm, (h) the ration of expansion during thge isenthropic process and (i) the overall ration of compression.
1.Refrigerator 1 simulates an ideal refrigerator and therefore operates on a Carnot cycle using R-134a as the refrigerant at a flow rate of 1.4 kg/sec. The condensing and evaporating temperatures are 30 °C and -10 °C, respectively. To assess the performance of Refrigerator 1, you must submit the report. of the project with the following information: a) Enthalpies corresponding to the states indicated in the cycle (1, 2, 3 and 4); b) The cooling rate (Q L ); c) The work supplied to the fluid by the compressor; d) The work generated by the turbine; e) The condenser heat rejection rate (Q H ); f) The coefficient of performance of the cycle. Important detail: For the energy balance, make the following considerations: ✓ Permanent regimen; ✓ Kinetic and potential energy variations are negligible; ✓ Compressor and turbine operate adiabatically; ✓ Evaporation and condensation steps are labor-free.
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 before the Isothermal compression stroke. Find a.) Qa, b.) Qr, c.) Whet (kJ/kg), d.) the efficiency (%), e) draw the T-S diagram with proper label of points, and f.) the pressures before and after Isothermal compression