Judge direct or indirect water hammer from valve-closure time versus wave travel time, compute the pressure rise, check pipeline safety and advise on slow-closing valves, surge tanks or air valves.
基于水锤波相理论判断直接/间接水锤，计算升压值并给出防护建议
| Item | Formula / Note | Source / Standard |
|---|---|---|
| Joukowsky water hammer formula | ΔH = a · Δv / g, where a is the wave speed and Δv the velocity change | Joukowsky N. (1898), On the hydraulic hammer in water mains |
| Wave speed | a = sqrt( K/rho ) / sqrt( 1 + ( K/E ) · ( D/e ) ), including pipe wall elasticity | Classical water hammer theory; GB/T 50265-2010, Design code for pumping station |
| Direct and indirect water hammer | Closure shorter than 2L/a gives direct water hammer; longer gives indirect | GB/T 50265-2010, Design code for pumping station |
| Protection measures | Common measures include surge tanks, slow-closing check valves and air valves | GB/T 50265-2010, Design code for pumping station |
水锤防护计算工具基于水锤波相理论，通过比较关阀时间与水锤波相时间，判断直接水锤或间接水锤，计算水锤压力升高值，评估危害程度，并给出针对性的防护方案建议，是输水管道与泵站设计的安全校核工具。