Process Equipment and Plant Design

In the case of a shell and tube heat exchanger, the logarithmic mean temperature difference ______________________?

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In the case of a shell and tube heat exchanger, the logarithmic mean temperature difference ______________________?

A. Is always less than arithmetic average value
B. Is always more than arithmetic mean value and the geometric mean value
C. Is always less than arithmetic mean value, but more than geometric mean value
D. May be either more or less than geometric mean and arithmetic mean value depending upon
whether the flow of stream is co-current or counter-current

For a cylindrical internally pressurised vessel, which of the following closure types would withstand highest pressure, if each closure is of the same material and thickness ?

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For a cylindrical internally pressurised vessel, which of the following closure types would withstand highest pressure, if each closure is of the same material and thickness ?

A. Hemispherical
B. Ellipsoidal (2 : 1)
C. Conical
D. Flat plate