CFD: An Effective Tool for Flow Simulation in Hydraulic Reaction Turbines

The reaction turbines have application in very wide range hydro power projects. The turbines are the most important components of any hydro power plant. Its cost varies 15-35% of the total cost of hydropower project. Thus the cost effective design of the turbine is of utmost importance. It is very crucial to understand the flow behavior of the turbine under various operating conditions. The model testing of turbines give overall performance of turbines based on global parameters. This approach is very costly and time consuming. But the detailed analysis of the performance of turbine is important under off-design and overloading conditions. Now-a-days computational fluid dynamics compliments experimental and theoretical approach by providing an alternate cost effective means of simulating real flow as it is much cheaper than experimental testing. In the present paper, the numerical flow simulation in reaction turbines ie, the axial and mixed flow turbines has been carried out to study effect of operating conditions on the local and global parameters of turbine. The simulation results for efficiency and output bear close comparison with experimental results. Key-words; axial flow turbine, CFD, mixed flow turbine, reaction turbines, runner