During maintenance, a valve in a water supply system needs to be shut. To avoid water hammer, the valve should be:
Closed gradually
In fluid mechanics, a water hammer is a pressure surge or wave caused when a fluid in motion is forced to stop or change direction suddenly. It commonly occurs when a valve is closed abruptly at an end of a pipeline system, and this sudden closure causes a pressure wave to propagate in the pipe.
To avoid water hammer, the valve should be:
- Left open: This option is not feasible as it contradicts the requirement to shut the valve during maintenance.
- Closed halfway: While this might reduce the flow, it does not solve the problem entirely as the valve needs to be completely shut at some point.
- Closed gradually: This is the correct answer. By closing the valve gradually, the change in flow is more controlled, and the pressure build-up is minimized. This gradual transition avoids the rapid pressure changes that lead to water hammer.
- Closed immediately: This action would cause a sudden stoppage of flow, potentially leading to a water hammer effect due to the abrupt change in pressure.
Thus, the valve should be closed gradually to prevent the occurrence of water hammer.
Similar Questions
A water pipe has a smooth interior. Over the time, scaling increases the roughness. What happens to the frictional head loss for the same flow rate?
Pipes of different diameters and lengths connected end to end to form a pipe line are called ________________.
Important Questions from Flow Through Pipes
The velocity of pressure wave in a rigid pipe carrying a fluid of density ‘ρ’, viscosity ‘µ’ varies as
In order to replace a pipe of diameter D by n parallel pipes of diameter d the relation used is
Darcy Weisbach equation is used to find loss of head due to -
To avoid vapourisation, pipe lines are laid over the ridge so that they are not more than _________ above the hydraulic gradient line.
The head of water over the centre of an orifice of diameter 20 mm is 1 m. The actual discharge through the orifice is 0.85 litre/s. Find the coefficient of discharge.
