Numerical Prediction of the Cavitation in Pumps

This paper presents a comparison between a coupled and a non-coupled approach for the prediction of the cavitation development in pumps. The coupling is defined here as the influence of the development of the cavitation on the main flow. Commercial CFD (computational fluid dynamic) software having a cavitation module and in-house developed code are used for this comparison. The intention of the authors is to evaluate these methods and their capabilities in predicting cavitating performance of pumps from an industrial point of view. In a first part, the two methods used are introduced and developed. In a second part, the results of these two approaches are compared for two impellers of the same specific speed having small geometrical differences leading to significant differences in the cavitation development. The ability and the benefits of the use of these different cavitation prediction approaches in the design process of a pump are finally discussed.