A Study on Blade Profile Optimization for Turbine Stages in a Rocket Engine Turbopump

Abstract

This study deals with an attempt to optimize blade profiles of 2-stage axial turbine section for a rocket engine turbopump, where the turbine section was originally designed by JAXA (Japan Aerospace Exploration Agency) in the project called DDT (Dynamic Design Team). An optimization based genetic algoriothm in cooperation with the surrogate-model constructed from RANS (Reynolds-Averaged Navier-Stokes' Eqs) simulations is applied to the blade profile exploration under two-dimensional flow condition to achieve the stage efficiency maximization, along with blade shape morphing. Out of the all calculated combinations of blades profiles for 1R (First Stage Rotor), 2S (Second Stage Stator) and 2R (Second Stage Rotor), top-30 highly efficient combinations are then picked up and three-dimensionalized so that each three-dimensional (3D) stage efficiency is calculated in order to check whether the highly efficient combinations via 2D optimization still perform good in 3D situation.