Hot water (0.01 m3

/min) enters the tube side of a counter current shell

and tube heat exchanger at 80°C and leaves at 50°C. Cold oil (0.05 m3

/min)

of density 800 kg/m3 and specific heat of 2 kJ/kg.K enters at 20°C. The log

mean temperature difference in °C is approximately

(A) 32

(B) 37

(C) 45

(D) 50

1 Answer

Answer :

(A) 32

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