Pipeline water hammer is triggered by____________________?
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Answer: B. Rapid pressure change due to a rapid change in the rate of flow
Explanation
Water hammer is a hydraulic shock wave phenomenon triggered by sudden velocity changes within a closed pipeline. When a valve closes rapidly, kinetic energy from the moving water column converts into intense elastic pressure waves. These rapid pressure transients travel back and forth through the piping network, creating violent mechanical vibrations. Fluid inertia and pipe wall elasticity combine to determine the intensity and speed of generated water hammer shock waves. The Joukowsky equation calculates the maximum pressure surge magnitude based on fluid density, acoustic wave speed, and velocity change. Preventing water hammer requires installing surge suppressors, air chambers, or implementing slow-closing valve actuation schedules.
Bursting of pipelines represents the potential destructive consequence of water hammer rather than the triggering mechanism itself. Stating pressure increase due to closure is incomplete without emphasizing the rapid rate of flow change required. Stating none of these is incorrect because rapid pressure change from rapid flow alteration triggers water hammer.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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