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[Kasimbi]

I have been reading several publications and articles that describe Surge analysis or water hammer analysis.I manage to get the formular for calcuting the pressure waves velocity(celerity), as well as the magnitude of surge pressure, but never the formular to calculate the change in velocity, which occurs.Anybody who can assits me on this please
Kasimbi

[fahood]

This is an interesting question but the answer is not simple at all. If you want to calculate the change in velocity and the subsquent pressure rise then you have to solve multiple differential equations which cannot be done analytically but there is well known computational method called the characterstic method which you need to program matlab code. However, you can get good estimate by simply taking total change in velocity. For example, you have initial velocity of 2 m/s for water pipe with wave speed of 1000 m/s, take the velocity goes to zero due to valve closure then the pressure rise can be found by

Dp=density * wave speed* velocity

Pressure rise in this case is 20 bar

Hope this helps