SUBJECT: THERMODYNAMIC COURSE: II ASSI.LACTURE: NATIQ ABBAS Example 2:- Refrigerant-134a enters the compressor of a refrigerator as superheated vapor at 0.14 MPa and -10°C at a rate of 0.05 kg/s and leaves at 0.8 MPa and 50°C. The refrigerant is cooled in the condenser to 26°C and 0.72 MPa and is throttled to 0.15 MPa. Disregarding any heat trans fer and pressure drops in the connecting lines between the components; determine (a) the rate of heat removal from the refrigerated space and the power input to the compressor, and (b) the coefficient of performance of the refrigerator. Solution: - P 0.14 MPa T--10 C h 246.36 kJ/kg P 0.8 MPa T 50 C h2 = 286.69 %3D AVERSIT P= 0.72 MPa T-26 C- - hg = 87.83 kJ/kg !! h3 =h, =87.83 KJ/kg h4 = h3 (throttling) h4 = 87.83 kJ/kg !! 0.S MPa 50°C 0.72 MPa 26 C 0.15 MPa 0.14 MPa -10°C SAMARRA RING

SUBJECT: THERMODYNAMIC COURSE: II ASSI.LACTURE: NATIQ ABBAS Example 2:- Refrigerant-134a enters the compressor of a refrigerator as superheated vapor at 0.14 MPa and -10°C at a rate of 0.05 kg/s and leaves at 0.8 MPa and 50°C. The refrigerant is cooled in the condenser to 26°C and 0.72 MPa and is throttled to 0.15 MPa. Disregarding any heat trans fer and pressure drops in the connecting lines between the components; determine (a) the rate of heat removal from the refrigerated space and the power input to the compressor, and (b) the coefficient of performance of the refrigerator. Solution: - P 0.14 MPa T--10 C h 246.36 kJ/kg P 0.8 MPa T 50 C h2 = 286.69 %3D AVERSIT P= 0.72 MPa T-26 C- - hg = 87.83 kJ/kg !! h3 =h, =87.83 KJ/kg h4 = h3 (throttling) h4 = 87.83 kJ/kg !! 0.S MPa 50°C 0.72 MPa 26 C 0.15 MPa 0.14 MPa -10°C SAMARRA RING

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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