Surge Analysis and Water Hammer

Pressure surge, water hammer, steam hammer, Joukowski pressure, transient forces, vapour cavity collapse. These are all terms associated with transient fluid flow events in a piping system which may be induced by normal operating events such as pump testing, system start up, system shut down …….

In short, flat systems these transient effects are often readily accommodated within the normal system design without special consideration. However, in longer systems and even short systems where there are significant changes in elevation these transient effects should be considered and designed for. Otherwise the systems may be vulnerable to unacceptable pressures and forces leading to equipment failure, loss of production, safety incidents, leakage, contamination and environmental damage.

System designers often struggle to determine whether specialist pressure surge advice should be obtained and if so at what point in the design process. As with all design the consequences of failure to consider pressure surge increase as a project progresses. A pressure surge screening study is often undertaken at an early stage but usually only considers the acceptability of potential peak pressures in a system due to valve closure. This severely underestimates the potential for transient events to cause problems both with safe design and reliable safe operation. Simple valve closure is rarely the straightforward cause of damage in a system which experiences problems.

At Spectrum we employ our expertise to help clients identify early in a project where the risks of transient events are likely to manifest in system operation and how to reduce risk for design and operation.

Projects include:

  • Cooling water and LNG loading systems, Yemen LNG Co, for Technip
  • Preliminary analysis of rising main, Thetford water treatment works, for AWG
  • Butane Network modifications, Wilton, UK for Huntsman Petrochemicals
  • Water metering system analysis, Nottingham UK, for Smartmeter Ltd
  • Diesel distribution systems, Ipswich, UK for Vopak
  • Debrining system analysis, E.ON Holford Gas Storage, UK
  • Firewater system analysis, Yemen, for Total