A two-stage, ideal cascade refrigeration system shown in Fig. 10.19 uses R134a as the working fluid in both cycles and replaces the ideal single-stage cycle of Problem 10.14. The mass flow rate through the first stage is OS kg/s.

The known properties are:
State 1: 160 kPa
State 7: 608C
Determine:
(i) The cooling load
(ii) The mass flow rate in system #2
(iii) The net compressor power
(iv) The coefficient of performance
(v) The percentage increase in the COP and the percentage decrease in compressor power compared with that of Problem 10.14

Transcribed Image Text:

aut (to surroundings) Condenser Compressor Throttle #2 n. Heat exchanger Throttle #1 Compressor Evaporator in (from cooled space)