The radiator in an automobile is a cross-flow heat exchanger (UAs = 10 kW/K) that uses air (cp = 1.00 kJ/kg·K) to cool the engine-coolant fluid (cp = 4.00 kJ/kg·K). The engine fan draws 30°C air through this radiator at a rate of 10 kg/s while the coolant pump circulates the engine coolant at a rate of 5 kg/s. The coolant enters this radiator at 80°C. Under these conditions, the effectiveness of the radiator is 0.4. Determine (a) the outlet temperature of the air and (b) the rate of heat transfer between the two fluids.

The radiator in an automobile is a cross-flow heat exchanger (UAs = 10 kW/K) that uses air (cp = 1.00 kJ/kg·K) to cool the engine-coolant fluid (cp = 4.00 kJ/kg·K). The engine fan draws 30°C air through this radiator at a rate of 10 kg/s while the coolant pump circulates the engine coolant at a rate of 5 kg/s. The coolant enters this radiator at 80°C. Under these conditions, the effectiveness of the radiator is 0.4. Determine (a) the outlet temperature of the air and (b) the rate of heat transfer between the two fluids.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter44: Geothermal Heat Pumps

Section: Chapter Questions

Problem 1RQ: Geothermal heat pumps, or water-source heat pumps, are classified as either _____loop or _____loop...

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