Influence on film cooling effectiveness of novel holes based on cylindrical configurations

Abstract

In this study, four novel film cooling hole designs, all based on cylindrical holes, are numerically evaluated, and compared with those of a simple cylindrical hole and a laterally-diffused shaped hole. Film cooling effectiveness and surrounding thermal and flow fields are documented for operation with various blowing ratios. It is shown that the two-stage cylindrical hole can improve film cooling effectiveness at higher blowing ratios. The primary hole with two secondary holes can enhance film cooling performance by creating anti-kidney vortex pairs that will weaken jet liftoff caused by the kidney vortex pair that is created by the primary hole. The tri-circular shaped hole provides better film cooling effectiveness values only near the hole, but worse at downstream positions. The two-stage structure for the tri-circular shaped hole provides better film coverage because it changes the flow structure inside the delivery channel and decreases jet penetration into the passage flow.

Acknowledgment

A part of work was carried out using computing resources at the University of Minnesota Supercomputing Institute.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (51676163), by the National 111 Project under Grant no. B18041, by the Fundamental Research Funds of Shenzhen City of China (JCYJ20170306155153048), and by the Fundamental Research Funds of Shaanxi Province (2015KJXX-12). This work is also supported by China Scholarship Council (CSC).