| In the history of the development process of the turbine, compared to the reaction turbines, Pelton turbines operate in higher head,and its related tech. nology of design and operation is more difficult, so its development generally lags behind the reaction turbines. In the Pelton turbine, the flow process is very complex, including the pressure loss, secondary flow, jet, sheet flow, spray, instability and complex interaction of the various components. In the actual operation, the flow contains sand particles of different concentrations and different sizes, so there are many abrasion factors in Pelton turbines, including fatigue abrasion, sand abrasion and cavitation abrasion and so on. Therefore, this paper dedicates to analyzing and studying the flow conditions of sand particles inside the sink, in order to explore the impact of sand abrasion inside the sink and put forward specific ideas and suggestions to reduce the sand abrasion.Firstly, this paper introduces the basic theory of jet, the basic situation of the jet in and out the sink, the force analysis of sand particles movement in the flow field and the collision theory of sand particles and solid. And then, build the Pelton model by UG, use the software of ANSYS ICEM to divide mesh, and finally use the software of Fluent for numerical simulation analysis.At last get the flow conditions of sand particles inside the sink.The erosion of Pelton turbine bucket wall mainly bases on three factors of particle sizes, particle velocity and particle concentration. When conducting numerical simulation analysis, we set up two variables of sand particle sizes and particle velocity, and calculate two situations:(1) at the same particle velocity and particle concentration, change the particle size,(2) at the same particle size and particle concentration, change the particle velocity, Finally get the influence of two factors of sand particle size and particle velocity on the state of the particle movement. |
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