Both C’s in a parallel-flow heat exchanger are equal to 156 W/K, U = 327 W/ m 2 .K and A = 2 m 2 . The hot fluid enters at 140°C and leaves at 90°C. The cold fluid enters at 40°C. If both C’s are...

Both C’s in a parallel-flow heat exchanger are equal to 156 W/K, U = 327 W/ m².K and A = 2 m². The hot fluid enters at 140°C and leaves at 90°C. The cold fluid enters at 40°C. If both C’s are halved, what will be the exit temperature of the hot fluid ?

Explain local and average value of skin friction coefficient.