Dynamic performance characterization of air valves
Proceedings of the 9th International Conference on Pressure Surge Analysis for Design and Operation
Kruisbrink A.C.H., Francisco Arregui de la Cruz, Carlos M., Bergant A.
Publish year
Ideas are presented on the dynamic performance characterisation of air valves. For this purpose the dynamics of air valve (float type), air pocket and pipe system are considered. From a parameter study and dimensional analysis, (dimensionless) dynamic air valve characteristics are developed. Results are presented for a vacuum breaking valve and combined vacuum breaking/air release valve, as obtained from large scale experiments at WL | Delft Hydraulics. The tests reveal that after valve closure always some residual air remains entrapped in the system, which is responsible for high pressure peaks. The (dimensionless) dynamic characteristics may be used in the estimation of the pressure surges due to the air valve closure, either by quick estimates or in numerical models, and enable the scaling to other valve sizes.