3. A one-shell pass and two-tube passes heat exchanger cools 1.8 L/s of oil (cp = 2.5 kJ/kg-K and density = 720 kg/m3) from 94 C to 48 C. Cooling water enters the tubes at 15 C and leaves at 40 C. The overall coefficient of heat transfer is 450 W/m2-K. Fouling of the tubes occurs, resulting in one-quarter of the tubes being blocked. The conditions remain the same except for the outlet temperatures. Determine the (a) oil exit temperature (1 dp) and (b) water exit temperature (1 dp) under the new condition.

3. A one-shell pass and two-tube passes heat exchanger cools 1.8 L/s of oil (cp = 2.5 kJ/kg-K and density = 720 kg/m3) from 94 C to 48 C. Cooling water enters the tubes at 15 C and leaves at 40 C. The overall coefficient of heat transfer is 450 W/m2-K. Fouling of the tubes occurs, resulting in one-quarter of the tubes being blocked. The conditions remain the same except for the outlet temperatures. Determine the (a) oil exit temperature (1 dp) and (b) water exit temperature (1 dp) under the new condition.

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 10.46P

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