The crucial role of air vacuum valve vertical position on producing secondary transient pressures

This paper studies how the importance of properly sizing AVVs on the basis of transient conditions varies with AVV location, This is performed by application of a variance based sensitivity analysis (ie., Sobol's method) In this study, a pump-pipe-reservoir system with a high point in the middle is considcred And a sudden pump failure is assumed The elevation of the high point is altered and the sensitivity analysis is performed for each resulting configuration. The results show that the severity of secondary transient pressure due to improper sizing of the AVV depends on thc vertical position of the AVV relative to the dosistream boundary In particular, results highlight the importance of designing AVVs based on transient response of the system at specific locations The results explored by this sensitivity study can be deemed as warnings even for more realistic water pipelines.