A Study of Silt Erosion on Inner Buckets of Pelton Turbines

Abstract

A 3-D model of pelton turbine bucket was built to investigate the motion characteristics of sediment particles in pelton turbines and the erosion caused by the movement. With the assistance of fluid analysis software FLUENT, A continuous phase turbulence model was estimated by the Euler equation which achieved convergence and the selected coupled calculation for solid-liquid two-phase flow with DPM model was built. It can be draw from the numerical analysis that, with the same size and sediment concentration, the inner bucket wall would suffer from the greater erosion by the relatively greater flow velocity; under the same condition of flow velocity and sediment concentration, the more serious erosion was caused by the bigger sized sediments; and the greater sediment concentration led to greater erosion, given the same flow velocity and sediment size. Based on the study, it showed that the erosion of inner wall of buckets was mainly affected by sediment size and concentration, as well as flow velocity.

A Comprehensive Review on Investigation of Sediment Erosion of Pelton Wheel Turbine

“…The enhancement rate in erosive wear for jet velocity fluctuates for different materials [17]. The silt erosion of the inner bucket increases with increasing jet velocity [20]. Jet velocity variations affect the torque significantly.…”

“…However, due to plastic deformation and plowing, erosive wear occurred along the bucket's depth [19]. Suwei (2015) performed a numerical investigation on erosive wear of the bucket of the hydro turbine using ANSYS Fluent. DPM, Grand, and Tabakoff models were used for erosion prediction.…”

“…It was found that erosion increased with velocity, silt concentration, and particle size. It was concluded that the silt size, concentration, and jet velocity influence erosive wear of the inner bucket of the turbine [20]. Alomar et al (2022) found that efficiency depends inversely on nozzle diameter.…”

“…The influence of silt particle concentration on erosion is more significant than silt particle size [23]. The silt concentration mainly influences the erosive wear of inner buckets [20]. The addition of sediment particles to the flow leads to a reduction in hydraulic efficiency [23].…”

“…This reduction in efficiency leads to a decrease in the power generation of the power plant. Erosion may also cause premature failure of major turbine parts, thus imposing a huge capital and maintenance cost on power plants [11].…”