Water hammer phenomenon: analysis and solutions

Abstract EN

Water hammer (hydraulic transient) is a complex phenomenon.

The cause of a hydraulic transient is the rapid change in the velocity of the flow in a closed pipe due to sudden power failure or sudden valve closure which generates high and low pressure waves transmit through the pipe line with a speed of sound.

The generated waves can cause serious problems in the pipeline system such as pipe burst, pumps and valves failure.

The aim of the study is to analyze experientially, theoretically and computationally to find out a solution for this phenomenon.

This was done through applying some practical methods techniques of water hammer control devices used in irrigation pumping systems.

In Salhia Agriculture Project site, Ismailia 33551 feddan were selected to carry out the water hammer investigation.

The steady state calculation was first executed to measure the flow rate and the head, unsteady state flow calculation was carried out to identify the maximum and minimum pressure during the sudden pump trips.

The results showed that the control devices such as the air vessels or surge tanks would mitigate the pressure rise and prevent the formation of negative pressure.

Water hammer analysis using AFT impulse program is an effective and reliable tool to choose the required surge protection device.

Installation of surge control device in the system such as one air vessel 50 m3 air volumes provides an acceptable level of protection to the irrigation pumping systems, as there are no cavitations at the pipeline and the maximum pressure reduces from 11 bars to 6 bars.

A good a agreement among the experimental, theoretical and computational associated results was found.