Pressure surges - experimental investigations and calculations with software codes

Within this paper an overview about six recently performed experimental pressure surge scenarios is given. Two scenarios are discussed in more detail. Three models of different physical depth are used to calculate cavitation hammer (first and second model) and the maximum length of the vapor bubble downstream a closing valve (third model), respectively. For the calculation of cavitation hammer two models are used, the full concentrate vapor cavity model and a three phase model. Moreover an innovative pipework modification to prevent high cavitation hammer is presented. This method requires the knowledge of the maximum length of a vapor bubble downstream a closing valve. In case of a simple pipe geometry this can be achieved by solving the momentum equation for the downstream water column (third model). In combination with the Joukowsky equation one can give a quite good estimation of the first cavitational hammer pressure peak without a software code necessary.