Question

Milk enters a heat exchanger at 20^{0}C and is heated to
75^{0}C using hot water at a temperature of
90^{0}C. 1) If exit temperature of water is
80^{0}C, assume parallel flow and determine the log mean
temperature difference between water and milk.

2) assume countercurrent flow and determine the log mean temperature difference between water and milk.

3)assume countercurrent flow and determine the overall heat
transfer coefficient of heat exchanger (based on inside diameter).
Assume specific heat of water as 4.18 kJ/(kg ^{0}C).

Answer #1

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