Consider a Carnot vapor refrigeration cycle with Refrigerant 134a as the working fluid. The cycle maintains a cold region at 40 °F when the ambient temperature is 90 °F. Data at principal states in the cycle are given in the table below. The states are numbered as in Fig. 10.1. Sketch the T-s diagram for the cycle and determine the a. temperatures in the evaporator and condenser, each in °R. b. compressor and turbine work, each in Btu per lb of refrigerant flowing. c. coefficient of performance. d. coefficient of performance for a Carnot cycle operating at the reservoir temperatures. Compare the coefficients of performance determined in (c) and (d), and comment. State 1 2 3 4 p (lbf/in.²) 40 140 140 40 Warm region at Tu Com wwwww Condenser Turbine Compressor Evaporator www Cold region at Te FIG. 10.1 Carnot vapor refrigeration cycle. h (Btu/lb) 104.12 114.95 44.43 42.57 TH Te s (Btu/lb. ºR) 0.2161 0.2161 0.0902 0.0902

Consider a Carnot vapor refrigeration cycle with Refrigerant 134a as the working fluid. The cycle maintains a cold region at 40 °F when the ambient temperature is 90 °F. Data at principal states in the cycle are given in the table below. The states are numbered as in Fig. 10.1. Sketch the T-s diagram for the cycle and determine the a. temperatures in the evaporator and condenser, each in °R. b. compressor and turbine work, each in Btu per lb of refrigerant flowing. c. coefficient of performance. d. coefficient of performance for a Carnot cycle operating at the reservoir temperatures. Compare the coefficients of performance determined in (c) and (d), and comment. State 1 2 3 4 p (lbf/in.²) 40 140 140 40 Warm region at Tu Com wwwww Condenser Turbine Compressor Evaporator www Cold region at Te FIG. 10.1 Carnot vapor refrigeration cycle. h (Btu/lb) 104.12 114.95 44.43 42.57 TH Te s (Btu/lb. ºR) 0.2161 0.2161 0.0902 0.0902

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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