In an open heart surgery under hypothermic conditions, the patient’s blood is cooled before the surgery and rewarmed afterwards. It is proposed that a concentric tube counterflow heat exchanger of length 0.5 m is to be used for this purpose, with a thin walled inner tube having a diameter of 55mm. If water at 60 ⁰C and 0.1kg/s is used to heat blood entering heat exchanger at 18 ⁰C and 0.05 kg/s. What is temperature of the blood leaving the heat exchanger? Uo= 500 W/m^2.K, Cpblood=3.5kJ/kg-K, Cpwater=4.183 kJ/kg-K.

In an open heart surgery under hypothermic conditions, the patient’s blood is cooled before the surgery and rewarmed afterwards. It is proposed that a concentric tube counterflow heat exchanger of length 0.5 m is to be used for this purpose, with a thin walled inner tube having a diameter of 55mm. If water at 60 ⁰C and 0.1kg/s is used to heat blood entering heat exchanger at 18 ⁰C and 0.05 kg/s. What is temperature of the blood leaving the heat exchanger? Uo= 500 W/m^2.K, Cpblood=3.5kJ/kg-K, Cpwater=4.183 kJ/kg-K.

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.14P

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