Design Optimization of Micro-Hydro Pelton Turbine: Integration of Static and Modal Analysis Using ANSYS APDL

Hydro energy offers more reliable, efficient and cost-effective solution compared to other form of renewable energy source for the production of electricity. However, issues such as proper choice of site for installation and huge investment for hydro power plant still a huge challenge. Further, operation of water turbine and its maintenance are also major concerns from the hydraulic engineering perspective. For an instance, hydropower turbine such as Pelton wheel turbine continuously operate in adverse conditions that may harm its strength, robustness, and stability for a long span. Further, the structure of turbine is compromised when the resonant frequency coincides with natural frequency of the structure due to dynamics stresses. Hence, in this research, both static structural and modal analyses are performed simultaneously to investigate the influence of dynamic load as well as pressure distribution on the bucket structure of Pelton turbine with the help of ANSYS®. The bucket is made of high strength material such as stainless steel. For both analyses, the identical constraint condition and boundary conditions are employed. Modal analysis is used for finding the vibrational frequencies of each mode using Block Lanczos method. On the other hand, the static structural analysis is performed to predict total distortion, von-Mises stress, and elastic strain distribution within bucket. The numerical model is based on proposed bucket geometry in the simulations. The results show that the bucket material has a maximum stress capacity of 69447 MPa which can readily bear the maximum stress from the maximum applied load. Further, the modal frequencies do not match with natural frequency, hence the resulting structural design is safe for operation at high impact of load.