EFFECT OF DIVERGENT RATIO ON PERFORMANCE OF VANELESS COUNTER-ROTATING TURBINE HIGH PRESSURE ROTOR

The redesign of a vaneless counter-rotating turbine(VCRT) is carried out after taking into account the circumferential and radial divergence of the high pressure rotor flowpath to select an adequate divergent ratio by using theoretical and numerical methods.The results show that the convergent ratio has great influence on the performance of the VCRT convergent-divergent high pressure rotor.Inner-extending shock waves from the high pressure rotor trailing edge are weaken or even eliminated by redesigning the high pressure rotor with an adequate divergent ratio,and the performance of the high pressure turbine improves.