Application of Computational Flow Dynamics Analysis for Surge Inception and Propagation for Low Head Hydropower Projects
Application of CFD for Surge in Hydropower Project
Keywords:
Surge, FLOW-3D, numerical model, Taunsa, RANSEAbstract
Determination of maximum elevation of a flowing fluid due to sudden rejection of load in a hydropower facility is of great interest to hydraulic engineers to ensure safety of the hydraulic structures. Several mathematical models exist that employ one-dimensional modeling for the determination of surge but none of these perfectly simulate real-time circumstances. The paper envisages investigation, inception and propagation of surge for a Low-Head Hydropower project using Computational Fluid Dynamics (CFD) analysis in FLOW-3D software. The fluid dynamic model utilizes Reynolds’ Averaged Navier-Stokes Equations (RANSE) for surge analysis. The CFD model is designed for a case study at Taunsa Hydropower Project in Pakistan which has been run for various scenarios keeping in view the upstream boundary conditions. The prototype results were compared with the results of physical model and proved quite accurate and coherent. It is concluded that CFD Model gives an insight of the phenomenon which are not apparent in physical model and shall be adopted in future for the similar low head projects. Its application will be helpful in limiting delays and cost incurred in the physical model testing.
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