(b) In a shell-and-tube heat exchanger, with one shell pass and four tube passes, water entering at 25°C and volume flowrate is being used to cool oil from 120°C. The mass flow rate of oil has recently been increased to 150 000 kg h-1. There is a total of 780 tubes of 5.0m length and 23.0mm outside diameter and 2 mm thickness. From the previous operation, the overall heat transfer coefficient of the exchanger is known to be 720 W m2K-1. Specific heat capacity of oil is 2100 J kg-1K-1. 175. 514 m3 h-1 (i) Use the &NTU method to find the exit temperature of the oil at the new flow rate. (ii) show, by calculation, how would the outlet oil temperature change if the oil mass flowrate would again increase by 28%, based on the value stated in the question (b).

(b) In a shell-and-tube heat exchanger, with one shell pass and four tube passes, water entering at 25°C and volume flowrate is being used to cool oil from 120°C. The mass flow rate of oil has recently been increased to 150 000 kg h-1. There is a total of 780 tubes of 5.0m length and 23.0mm outside diameter and 2 mm thickness. From the previous operation, the overall heat transfer coefficient of the exchanger is known to be 720 W m2K-1. Specific heat capacity of oil is 2100 J kg-1K-1. 175. 514 m3 h-1 (i) Use the &NTU method to find the exit temperature of the oil at the new flow rate. (ii) show, by calculation, how would the outlet oil temperature change if the oil mass flowrate would again increase by 28%, based on the value stated in the question (b).

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 10.12P

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