Pelton Turbines

Introduction.- Working principle of Pelton turbines.- Injector characteristics.- Jet characteristics and measurements.- Interaction between the jet and Pelton wheel.- Fluid mechanics in the rotating bucket.- Water spreading in the rotating bucket.- Exit flow conditions.- Exit flows and hydraulic losses.- Fricton effects and flow friction theorem.- Viscous cross-flow through the bucket.- Viscous longitudinal flow through the bucket.- Friction and windage losses in Pelton wheels.- Power loss due to bearing frictions.- Hydraulic and mechanical efficiency.- Real hydraulic efficiency characteristics.- Runaway speed and acceleration profile.- Hydraulic design of Pelton turbines.- Multi-jet Pelton turbines.- Geometric and hydraulic similarities.- Model turbine tests and efficiency scale-up.- Sand abrasion and particle motion in the bucket flow.- Bucket mechanical strength and similarity laws.- Appendices: Nomenclature.- Definition of derived parameters.- Specific speed and application in Pelton turbines.- Specification of the jet piece for a bucket.- Specification of the bucket positions.- Particle motion along the streamlines in the Pelton Bucket.