Refrigerant-134a enters an adiabatic compressor at -30oC as a saturated vapor at a rate of 0.45 m3 /min and leaves at 900 kPa an

Question

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Refrigerant-134a enters an adiabatic compressor at -30oC as a saturated vapor at a rate of 0.45 m3 /min and leaves at 900 kPa an

d 55oC. Determine (a) the power input to the compressor, (b) the isentropic efficiency of the compressor, and (c) the rate of exergy destruction and the second-law efficiency of the compressor. Take T0

Engineering

1 answer:

saw5 [17] · Answer 1 · 2022-06-01T01:26:49+03:00

Answer:

a) 1.918 kw

b) 86.23%

c) 0.26 kw

Explanation:

Given data:

T1 = -30°C = 243 k , T0 = 27°C

using steam tables

h1 = 232.19 KJ/kg

s1 = 0.9559 Kj/Kgk

T2 = 55°C P2 = 900 kPa

Psat = 1492 kPa, h2 = 289.95 Kj/Kg, s2 = 0.9819 Kj/kgk , m = 0.0332 kg/s

a) Determine the power input to the compressor

power input = 1.918 kw

b) Determine isentropic efficiency of compressor

Isentropic efficiency = 86.23%

c) Determine rate of exergy destruction

rate = 0.26 kw

Attached below is the detailed solution of the given problems