05 - Propulsion
EFFECT OF COMPLEX FLOW PROFILES AT COMBUSTOR EXIT ON TURBINE CHARACTERISTICS
Y.F. Li¹, Z.Z. Na¹, Y. Chen¹, Y.B. Wang¹; ¹AECC, China
The flow profile at the exit of the aero-engine combustor has the characteristics of strong complex swirl, circumferential and radial temperature nonuniformity. With the increase of combustor temperature-rising level and the trends toward short annular and strong jet cooling combustors, the out flow from combustor becomes more nonuniform (represented by Max (OTDF)). After the high-temperature and high-pressure gas produced by the combustor enters the turbine stator blades, the specific and complex flow profile forms under the influences of turbine secondary flow, cooling air and rotor-stator interaction including horseshoe vortex on cascade end wall, corner vortex and passage vortex. rnUnder this background, the studies of the turbine flow characteristics influenced by the hot streaks, NGV clocking and the direction of the swirl is of vital importance in order to explore the turbine design method considering the exit flow profiles of the combustor. In this paper, the above-mentioned studies were carried out through numerical simulation considering computational accuracy and computational costs comprehensively. Numerical analysis method for engineering design and application was discussed. Based on the simplified typical combustor outlet flow profiles, the effects of hot streak, swirl directions and clocking positions on the turbine characteristics were obtained.rnThe research indicates that the hot streaks and swirl directions have little influence on turbine performance, while they have great influences on the temperature distribution of stator blades and rotor blades. At the specific clocking position, the local high temperature region on blade can be avoided, which is significant to improve blade reliability. Based on these studies, the numerical investigation of the local high temperature region of the turbine casing caused by the distortion of the temperature profile at the exit of the combustor wa