Mechanisms of Hydro-Abrasive Erosion and Solutions to Countr these Problems

Due to the extensive problems with a high concentration of hard particles in the water going through turbines in India the paper gives an overview over the mechanisms and solutions from the design and the protection point of view. The different damaging mechanisms of particles depending on the size and the location of abrasion on a profiled surface are being described, showing the influence of the boundary layer for the two extremes of quasi-laminar or turbulent condition. After that a short overview of different optimization processes to minimize the wear are given. Here aso examples of design changes are given. The last chapter focuses on the state of the art of coating systems and shows on one example the effectiveness of the coating system of Voith Siemens Hydro.