密度比对弯扭导叶扇形孔气膜冷却效率的影响

The influences of density ratio and mass flow ratio on the full coverage film cooling effectiveness of a bowed and twisted high pressure turbine 1st stage vane were studied experimentally in a fan-shaped cascade wind tunnel. The pressure sensitive paint technique was used to measure the film cooling effectiveness of the vane. Results showed that the film cooling effectiveness increased with increasing density ratio and mass flow ratio. When the density ratio increased from 1.0 to 2.0，the spanwise averaged film cooling effectiveness increased by 6% to 32%. The film cooling effectiveness only had a minor increase when the density ratio increased from 1.0 to 1.5. However，it had a great increase when the density ratio increased from 1.5 to 2.0，meaning that the relationship between film cooling effectiveness and density ratio was non-linear.