Water hammer occurs when flowing water is abruptly stopped by valve closure. The resulting pressure surge magnitude depends on___________________?
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Answer: D. All A., B. and C.
Explanation
The Joukowsky equation proves that water hammer pressure surge magnitude depends directly on fluid velocity and acoustic wave speed. Valve closure time determines whether the transient is classified as rapid or gradual, directly scaling the resulting pressure spike. Longer pipelines store more moving fluid mass, amplifying the total kinetic energy converted into destructive pressure waves. Pipeline length dictates the reflection time of pressure waves traveling back and forth between the closed valve and reservoir. Initial fluid velocity determines the total kinetic energy that must be arrested during the sudden valve closure event. Pipe wall elasticity and material stiffness dictate acoustic wave propagation speeds, influencing overall surge pressure intensity.
Isolating pipe length ignores the equally critical roles played by fluid velocity and valve closure timing parameters. Focusing solely on fluid velocity neglects how pipe elasticity and closure time alter the final pressure surge magnitude. Restricting the answer to valve closure time ignores the direct proportionality to pipe length and initial fluid velocity.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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