Toward design optimization of a Pelton turbine runner

Christian Vessaz (1) , Loïc Andolfatto (1) , François Avellan (1) , Christophe Tournier (2)

1 LMH - Laboratoire de Machines Hydrauliques
2 LURPA - Laboratoire Universitaire de Recherche en Production Automatisée

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. A cubic multivariate adaptive regression spline surrogate model is built according to the simulated performance of these runners. Moreover, an original clustering approach is proposed to decompose the design problem into four sub-problems of smaller dimensions that can be addressed with more conventional optimization techniques.

Mots clés: Pelton turbine; Bucket shape parameterization; Design optimization; High-dimension; Finite volume particle method

Domaines: Mécanique des fluides [physics.class-ph]; Génie mécanique [physics.class-ph]

Christian Vessaz, Loïc Andolfatto, François Avellan, Christophe Tournier. Toward design optimization of a Pelton turbine runner. Structural and Multidisciplinary Optimization, 2017, ⟨10.1007/s00158-016-1465-7⟩. ⟨hal-01521737⟩