Numerical simulation of six jet Pelton turbine model

Hydraulic turbines are designed for the given values of head, discharge and speed but mostly operate at off designed head and discharge values. Due to variation in head, operating parameters like speed and discharge coefficients are changed affecting the flow and efficiency characteristics of turbine. This makes customary to assess the turbine performance at different operating parameters. Pelton turbine is the most commonly used impulse turbine for high head power plants. The computational fluid dynamics is a cost effective tool to assess the turbine performance in terms of local and global design and operating parameter of turbine. In the present work, multiphase flow analysis in Pelton turbine using water and air as working fluid is carried out to estimate the efficiency, blade loading, velocity and water distribution over the bucket at different operating regimes of the turbine. The effect of mesh size, turbulence model and time step is also studied for transient multiphase flow simulation.