Massively Parallel Simulation of the Unsteady Flow in an Axial Turbine Stage

Abstract

The results from two numerical simulations of the unsteady flow in a 11 stage axial-flow turbine are presented and compared with experimental data to show both the effect of blade count on the solution accuracy and the time-averaged and unsteady flow physics present. TFLO, the three-dimensional, multiblock, massively parallel turbomachinery flow solution procedure is used to simulate the flow through the Aachen 36-vane/41-blade/36-vane 1 ½-stage turbine rig. Comparisons of the time-averaged and unsteady flow solutions of 1-vane/1-blade/1-vane and 6-vane/7-blade/6-vane configurations with the available experimental data are used to show the importance of matching actual blade counts in unsteady flow simulations as closely as possible. In addition, these comparisons are used to quantify the predicted aerodynamic performance differences and highlight the different unsteady flow physics in the two simulations.