A very long, concentric tube heat exchanger is having hot and cold water inlet temperature of 85°C and 150°C. The flow rate of the hot water is twice than that of the cold water. Assuming equivalent...

A very long, concentric tube heat exchanger is having hot and cold water inlet temperature of 85°C and 150°C. The flow rate of the hot water is twice than that of the cold water. Assuming equivalent hot and cold water specific heats, determine the water outlet temperatures and the heat exchanger effectiveness for the following modes of operation: (i) counter-flow, and (ii) parallel-flow.