Resumo:
This work presents a methodology for the conceptual design of Pelton turbines, where
configurations or dimensions are determined as a function of the nominal load condition. To
determine the energy and hydraulic efficiency of the turbine, losses in terms of specific
energy are introduced, and leakage and mechanical losses are then considered. This
methodology allows obtaining the spatial coordinates that represent the concave surface of the
bucket. The preliminary results of the project are compared with a numerical model in
transient regime (CFD), procedures and methodologies for the simulation are presented in
details, such as the construction of the mesh in the non-inertial domain, represented by five
buckets and sliding mixing interfaces between the inertial and non-inertial domains. The
multiphase, VOF and turbulence k-ω / SST models were selected considering step time values
around 0.000185 s., in order to represent the instantaneous torque resulting from the
interaction between the buckets and the jet. Simulation results were extended to analysis of
hydraulic efficiency, at the design point and at part load.