A heat exchanger as shown in the below figure is used for an air conditioning system through a chilled water. Hot air at bar and 37 °C enters the heat exchanger at a volume flowrate of 1 m3/s leaving at 20 °C. The chilled water enters the heat exchanger at 5 °C and 1.5 bar and leaves as warm water at 12 °C and same pressure. The heat transfer from the outer surface of the heat exchanger is neglected. Similarly, the kinetic and potential energy difference in both the air a water at the inlet and exit is negligible. Assume constant specific heats for water and for air. At steady state operation, determine: (a) The mass flowrate of the water, and (b) The rate of heat transfer between the water and the air in kW.

A heat exchanger as shown in the below figure is used for an air conditioning system through a chilled water. Hot air at bar and 37 °C enters the heat exchanger at a volume flowrate of 1 m3/s leaving at 20 °C. The chilled water enters the heat exchanger at 5 °C and 1.5 bar and leaves as warm water at 12 °C and same pressure. The heat transfer from the outer surface of the heat exchanger is neglected. Similarly, the kinetic and potential energy difference in both the air a water at the inlet and exit is negligible. Assume constant specific heats for water and for air. At steady state operation, determine: (a) The mass flowrate of the water, and (b) The rate of heat transfer between the water and the air in kW.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.12P

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