Problem 2 A counterflow heat exchanger with both fluids (i.e., water and air) being unmixed. The water has a flow rate of 0.07 kg/s, enters the heat exchanger at 400 K and leaves at 300 K. The water is cooled by air that enters at 0.75 kg/s and 250 K. Cp for the water and air are 4200 J/kg.K and 1007 J/kg K, respectively. 1. Explain how do you calculate the rate of transfer for a heat exchanger. 2. If the overall heat transfer coefficient is 150 W/m² K, Calculate the total heat transfer rate through this heat exchanger? 3. What if you use a parallel flow heat exchanger instead of the counter flow heat exchanger, determine the total heat transfer rate? 4. What are the main differences between parallel and counter flow heat exchangers and which heat exchanger is better for refrigeration and air conditioning application.

Problem 2 A counterflow heat exchanger with both fluids (i.e., water and air) being unmixed. The water has a flow rate of 0.07 kg/s, enters the heat exchanger at 400 K and leaves at 300 K. The water is cooled by air that enters at 0.75 kg/s and 250 K. Cp for the water and air are 4200 J/kg.K and 1007 J/kg K, respectively. 1. Explain how do you calculate the rate of transfer for a heat exchanger. 2. If the overall heat transfer coefficient is 150 W/m² K, Calculate the total heat transfer rate through this heat exchanger? 3. What if you use a parallel flow heat exchanger instead of the counter flow heat exchanger, determine the total heat transfer rate? 4. What are the main differences between parallel and counter flow heat exchangers and which heat exchanger is better for refrigeration and air conditioning application.

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.

Chapter10: Heat Exchangers

Section: Chapter Questions

Problem 10.40P

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