Surge Analysis

It is essential that hydraulic systems are analysed for potential pressure surge risk; that appropriate pressure surge mitigation is designed; and that design and operations staff have a good understanding of the nature of the pressure surges they are controlling.

Engineering and water companies are often unaware of the severity of the risks associated with pressure surge (water hammer) in their systems. Many consultants have purchased or developed expensive surge analysis software, but surge analyses are often undertaken by relatively inexperienced individuals. This approach can have serious implications as catastrophic pressure surge events are often: missed, not analysed, or misinterpreted.

Peter Glover Consulting Ltd provide a complete surge analysis package to our clients by providing full pressure surge analysis, technical presentations of surge analysis findings, training for hydraulic designers, operators and potential surge modellers. We also review and check pressure surge work done by others, and assist such individuals in developing sound strategies for surge analysis and surge control. 

How can you determine whether pressure surge is going to cause a problem?

This depends on the nature of the transient, and the system on which it acts. An experienced surge (transient) analyst can get a good understanding for whether a system is likely to have a problem or not by doing some simple calculations, and observing the system profiles. It is essential to have a thorough understanding of the physics of pressure surge in order to do this. 

Peter Glover Consulting Ltd offers a one day training course that can enable your experienced hydraulic engineers to consider their designs from a pressure surge perspective. As a result of this course, designers are able to predict whether a full surge analysis is required, and what type of solutions are likely to work, and to undertake preliminary design of potential pressure surge control solutions.For situations in which problems are anticipated, it is necessary to undertake computer modelling of the network. It is important that this is undertaken under expert guidance as a large number of computer modelling results can easily cloak potential pressure surge catastrophes.

What causes a Pressure Surge (Hydraulic Transient)? 

Anything that causes an immediate change in flow velocity, causes a pressure surge. This pressure surge is called a hydraulic transient. 

A hydraulic transient (pressure and flow surge) continues until the system settles down to a new steady state condition ( water flowing steadily or not). Problem transients or pressure surge are often caused by the starting and stopping of pumps, rapid valve closure, air entrainment, check valves, air valves, even surge anticipating valves, guide vane closure, generator load rejection, turbine startup, and a myriad of other causes. 

A transient will typically propagate throughout a system, and at a given position on a network a variety of different transient pressures and velocities can superimpose causing more extreme events.