The objective of the present paper is to perform numerical simulations of a high-speed water jet impinging on rotating Pelton buckets using the finite volume particle method (FVPM), which combines attractive features of smoothed particle hydrodynamics (SPH) and conventional grid-based finite volume. The particles resolution is first validated by a convergence study. Then, the FVPM results are validated with available measurements and volume of fluid (VOF) simulations. It is shown that the pressure field in the buckets inner wall is in good agreement with the experimental and numerical data and the evolution of the flow pattern matches the high-speed visualization.

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The objective of the present paper is to propose a strategy to optimize the performance of a Pelton runner based on a parametric model of the bucket geometry, massive particle based numerical simulations and advanced optimization strategies to reduce the dimension of the design problem. The parametric model of the Pelton bucket is based on four bicubic Bézier patches and the number of free parameters is reduced to 21. The numerical simulations are performed using the finite volume particle method, which benefits from a conservative, consistent, arbitrary Lagrangian Eulerian formulation. The resulting design problem is of High-dimension with Expensive Black-box (HEB) performance function. In order to tackle the HEB problem, a preliminary exploration is performed using 2'000 sampled runners geometry provided by a Halton sequence.

In a conventional design and manufacturing process, turbine blades are modeled based on reverse engineering or on parametric modeling with Computer Fluids Dynamics (CFD) optimization. Then, only raises the question of the manufacturing of the blades. As the design does not take into account machining constraints and especially tool path computation issues in flank milling, the actual performance of the machined blade could not be optimal. In this paper, a new approach is used for the design and manufacture of turbine blades in order to ensure that the simulated machined surface produces the expected hydraulic properties. This consists in the modeling of a continuous tool path based on numerical simulation rather than the blade surface itself. Consequently, this paper aims at defining the steps of the proposed design approach including geometrical modeling, mesh generation, CFD simulation and genetic optimization.The method is applied on an isolated blade profile in a uniform water flow and results are compared to the conventional design process.

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