Consider a parallel-flow heat exchanger with area Ap and a counter-flow heat exchanger with area Ac. In both the heat exchangers, the hot stream flowing at 1 kg/s cools from 80 C to 50 C. For the cold stream in both the heat exchangers, the flow rate and the inlet temperature are 2 kg/s and 10 C, respectively. The hot and cold streams in both the heat exchangers are of the same fluid. Also, both the heat exchangers have the same overall heat transfer coefficient. The ratio Ac /Ap is _____.

Consider a parallel-flow heat exchanger with area Ap and a counter-flo

1.	Consider a parallel-flow heat exchanger with area A_p and a counter-flow heat exchanger with area A_c. In both the heat exchangers, the hot stream flowing at 1 kg/s cools from 80 C to 50 C. For the cold stream in both the heat exchangers, the flow rate and the inlet temperature are 2 kg/s and 10 C, respectively. The hot and cold streams in both the heat exchangers are of the same fluid. Also, both the heat exchangers have the same overall heat transfer coefficient. The ratio A_c /A_p is _____.
A.	0.927
B.	0.244
C.	0.945
D.	0.955
Answer» B. 0.244

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