In a counter-flow heat exchanger, water is heated at the rate of 1.5 kg/s from 40 C to 80 C by an oil entering at 120 C and leaving at 60 C. The specific heats of water and oil are 4.2 kJ/ kgK and 2 kJ/kgK, respectively. The overall heat transfer coefficient is 400 W/m2K. The required heat transfer surface area (in m2) is

In a counter-flow heat exchanger, water is heated at the rate of 1.5 k

1.	In a counter-flow heat exchanger, water is heated at the rate of 1.5 kg/s from 40 C to 80 C by an oil entering at 120 C and leaving at 60 C. The specific heats of water and oil are 4.2 kJ/ kgK and 2 kJ/kgK, respectively. The overall heat transfer coefficient is 400 W/m2K. The required heat transfer surface area (in m2) is
A.	0.104
B.	0.022
C.	10.4
D.	21.84
Answer» E.

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