Abstract:

ESDU 84013 provides a simplified graphical method for predicting maximum pressure changes in liquid filled pipework systems that may be treated as one-line systems. The method applies to pressures induced by partial or total valve closure, covering all common valve types, or pump trips. Data are also given for the estimation of the size of air vessel, situated just downstream of a pump, to protect against excessive upsurge and downsurge pressure changes following pump trip. A Basic program listing is included to analyse transients in one-line systems and does not use the simplifying assumptions necessary for the graphical data. Practical worked examples, illustrating the use of the methods, are included and guidance is given on the data required for a full fluid transients analysis going beyond the scope of ESDU 84013.