A fluid is flowing inside the inner tube of a double pipe heat exchanger

with diameter 'd'. For a fixed mass flow rate, the tube side heat transfer co￾efficient for turbulent flow conditions is proportional to

(A) d

0.8

(B) d

-0.2

(C) d

-1

(D) d

-1.8

1 Answer

Answer :

(B) d

-0.2

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