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Doctors Medicines MCQs Q&A

A designer chooses the values of fluid flow rates and specific heats in such a manner that the heat capacities of the two fluids are equal. A hot fluid enters the counter flow heat exchanger at 100°C and leaves at 60°C. A cold fluid enters the heat exchanger at 40°C. The mean temperature difference between the two fluids is

A designer chooses the values of fluid flow rates and specific heats in such a manner that the heat capacities of the two fluids are equal. A hot fluid enters the counter flow heat exchanger at 100°C and leaves at 60°C. A cold fluid enters the heat exchanger at 40°C. The mean temperature difference between the two fluids is Correct Answer 20°C

tm = mean temperature difference between the two fluids for counter flow heat exchanger
tm = th1 - tc2 = th2 - tc1
tm = th2 - tc1 = 60 - 40 = 20.

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