Question

Overall heat transfer co-efficient of a particular tube is U1. If the same tube with some dirt deposited on either side has coefficient U2, then

a.

U1 = U2

b.

U2 > U1

c.

U1 > U2

d.

U1 = dirt factor - U2

Answer: (a).U1 = U2

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Q. Overall heat transfer co-efficient of a particular tube is U1. If the same tube with some dirt deposited on either side has coefficient U2, then

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