Numerical Analysis of Three-Dimensional Unsteady Hot Streak Migration and Shock Interaction in a Turbine Stage

Abstract

A three-dimensional unsteady flow computation has been performed for a transonic first turbine stage under the influence of streaks of hot gas exiting the combustion chamber. Realistic flow conditions are obtained by using an unequal stator-to-rotor pitch, a single-streak/multistator channel configuration, and periodic boundary conditions. The resulting unsteady shock wave system and the hot streak migration as well as the shock wave/streak interaction are presented and discussed. In addition, the time average of the periodic unsteady solution is analyzed and compared with a steady-state computation. The steady-state solution is analyzed and compared with a steady-state computation. The steady-state solution matches the time-averaged one in terms of the pressure field and the maximum stagnation temperature on the rotor blade surface. However, the rotor blade temperature patterns are different with a stronger radial secondary flow present in the time-averaged solution due to the retention of the circumferential streak variations at the stator/rotor interface.