Study of Hot Streak Effects in a Counter-Rotating Turbine

Abstract

Based on its convection nature, some influences of the hot streak on a 1+1 (with inter-blade vane) counter-rotating turbine are studied by using a three-dimensional (3D) unsteady Euler solver. Emphasis is laid on the hot streak effect to the blade heat load and the clocking effects between hot streak and blade rows. One temperature distortion magnitude, two spanwise and four tangential positions, four clocking locations between vanes of first and second stage are examined. Results show that the effect of the hot streak on a counter-rotating turbine is nearly the same as a conventional turbine. However, clocking between the hot streak and the vane of the high pressure turbine (HPT) exerts significant influences on the heat load of the whole HPT stage. Also, clocking between the HPT vane and the vane of the low pressure turbine (LPT) affects the heat load of the LPT greatly. These effects cannot be captured with the steady flow assumption. So time accurate simulation about the hot streak/blade interaction must be used as a basis for the turbine design and optimization.