Chemical Engineering - Fluid Mechanics - Discussion

"Bursting of pipelines due to closure by a valve".

Bursting can be a result of water hammer, but not its cause.

"Rapid pressure change due to a rapid change in the rate of flow". This is Exactly correct — this is the definition of water hammer.

"Pressure increase due to closure of a valve resulting in decrease in rate of flow". It's Close, but not as general or accurate as the correct answer.

Also implies a slower change, which would not cause hammer.

Water hammer (or, more generally, fluid hammer) is a pressure surge or wave caused when a fluid (usually a liquid but sometimes also a gas) in motion is forced to stop or change direction suddenly (momentum change). Water hammer commonly occurs when a valve closes suddenly at an end of a pipeline system, and a pressure wave propagates in the pipe. It is also called hydraulic shock.

Here in option B they used "rapid" word, in option C simply closing of valve is mentioned which is general practice in all the industries does not mean that hammering take place. If there is rapid change in pressure then only hammering is occured.

Water hammers occur when in a moving fluid the valve is closed all of a sudden due to which there is a heavy pressure increase. And according to this option[C] becomes the most apt option.

Water hammer means a getting some voice like a hammer from a water pipeline, and it is happening by a rapid change in pressure of water, so option C suits.

Yes more appropriate is C, because when the valve is closed the back pressure increases this gives more hammering of liquid to the wall of pipe.

The most appropriate answer is C as it occurs due to closure in wall specifically, pressure may also changes due to other reasons.

If valve is closed the flow of fluid will occurs rapids so most appropriate answer is B.

The answer is "c" it occurs only when there is sudden close in the pipeline.

What is mean by water hammer? Can anyone please explain this concept?