Accuracy and parameter estimation of elastic and viscoelastic models of the water hammer

The water hammer problem is considered, one of the most important questions of unsteady flows in pipelines. Although first mentioned in the scientific literature more than a hundred years ago and widely analyzed since in many research centers, the problem is not fully recognized yet. It may be considered on two levels: practical and theoretical. In both cases, several difficulties arise rendering the results less than fully satisfactory. The most important difficulties are the proper mathematical description of the phenomenon, the choice of the solution method, estimation of the model parameters and numerical aspects of solving the equations governing the phenomenon’s run. They are presented in the paper and typical approaches to their solution are discussed. Numerical solutions are compared with experimental results.