边倒圆型气膜孔流动换热特性研究

In order to get higher film cooling performance, a new structure called radiusing-type hole was proposed based on cylinder hole and the interaction between mainstream and jet of film cooling. Medication of radiusing was used near the leading edge of film cooling hole. Experiments and numerical simulations were conducted to figure out the flow and heat transfer performance of radiusing-type hole. Film cooling characteristics downstream of the hole and discharge coefficient were studied. Results show that flow structure within the radiusing-type hole is more uniform than cylindrical hole which leads to weaker kidney vortex pairs in main flow. Normal momentum of jet is weaker and lateral momentum is stronger because of the expanding effect of radiusing-type hole, these two factors improve film cooling performance. For radiusing-type hole, the film attach on the wall better and cover wider area. In the region downstream the exit of radiusing-type hole, heat transfer coefficient is high, along the stream wise direction heat transfer coefficient is sharply decreased. The discharge coefficient of radiusing-type hole is 5% higher than cylindrical hole. In general, radiusing-type hole has better flow and heat transfer characteristics.