2D Cascade CFD Validation of an Axial Hydraulic Turbine's Guide Vane and Runner Blade

Project Overview

This project focused on a two-dimensional cascade Computational Fluid Dynamics (CFD) validation of the guide vane and runner blade profiles for an axial hydraulic turbine. The objective was to verify the consistency of design tool predictions with resolved viscous flow solutions before committing to more complex 3D simulations or physical prototyping. Steady incompressible Reynolds-averaged Navier-Stokes (RANS) simulations, employing the k-omega SST turbulence model, were conducted on single-passage cascades across six radial stations for both blade rows. Rigorous grid convergence studies ensured solution accuracy. The guide vanes demonstrated significant over-turning, delivering up to 6.5 degrees more swirl than designed. Conversely, runner blade simulations showed excellent agreement between integrated forces and momentum balance, and exit angles matched design within two degrees. However, the design tool was found to overestimate spanwise loading towards the runner blade tip.