Because of the importance of water hummer and it’s big impact in
pumping pipes, an analytical study of water hummer resulting from
the pumping station abruptly stopped working (due to a power
outage on water pipe line that conveys water from groun
d open tank
to three overhead open tanks was conducted, and without means of
protection from water hummer .
maximum and minimum pressure values and the location of each of
them in the network have been identified.
It was found that the pump trip caused a transient state with
negative pressure along the pipe system. The values of maximum
pressure were less than the pressure tube run.
An analytical study was done to explain the
relationship between the performance of gas accumulator, surge
tank and vacuum breaker valve and the profile of the pipe.
The study proved that effectiveness of protection means vary
according to the longitudinal path of pipe.
Analysis study was done to explain the effect of the
longitudinal section on the values of pressure of the water
hammer resulting from the trip of pumps, which results a low
pressure wave often lead to get cavitation, has been shown from
the anal
ytical study of several profiles and compare the results,
that the shape of the profile and the level of the pressure line
after the stopping of pumps determines the type of cavitation
formed , the region in which it occurs and the pressure values
resulting from it, when the profile doesn’t contain bends or the
bends are below the level of line pressure a distributed
cavitation is occurred, In the case of the presence of high points
, the effect of the bend is linked to several factors:
1 - the greater the height of the bend above line pressure increases the possibility for column separation and increases the pressure
forces.
2 –the pressure forces increase whenever the bend closer to the pumps.
