Numerical Analysis of Flow Characteristics in a Penstock Using COMSOL Multiphysics

In this analysis, computational fluid dynamics (CFD) analysis of the penstock used in the hydropower plants was performed using the finite element method (FEM) by using COMSOL Multiphysics. The simulation is conducted in order to explore the differences in the flow behaviour, pressure distribution, and velocity profiles along the penstock geometry in the conditions of changing the inlet velocity (1 m/s, 2 m/s, 3 m/s, and 4 m/s). Turbulent Flow, k-epsilon interface is used whereby the trend of high Reynolds number flows are captured in case of hydropower conduits. Penstock model has features such as curvature and inclination to give them correspondences with real-life flow conditions. As demonstrated, variations in velocity gradients and dynamic pressure are much more considerable with appreciating inlet velocity, making it clear that robust structural design is required at greater flow rates. The zones of recirculation and secondary flow, especially close to bends, can be viewed using streamline visualizations that are vital in the evaluation of the loss of energy. The parametric study gives an understanding of how best to design the penstock in order to achieve better hydraulic performance and reliability of renewable systems.