Question

The more rapid the closure of the valve, greater is the water hammer pressure developed.

(a) True

(b) False

The question was posed to me in unit test.

This interesting question is from Pressure Conduites topic in chapter Pressure Conduits, Outlet Works through Dams and Rivers of Irrigation Engineering

Answer 1

Correct answer is (a) True

Easy explanation: When a liquid is flowing in a pipeline is abruptly stopped by the closing of the valve, it destroys the momentum and retards the velocity of water column behind. This exerts a thrust on the valve, an additional pressure on the pipe shell and it may be so high as to cause bursting of the pipe shell. The more rapid is the closure of the valve, the more rapid is the change in momentum and hence, greater hammer pressure is developed.