Experimental and Numerical Investigation on the Film Cooling of Cylindrical Holes Embedded in a Trench
Experimental measurement and numerical simulation are carried out to investigate the film cooling character and physics of cylindrical holes embedded in a transverse trench. The design of trench holes reduces significantly the effort of hole manufacturing by coating with thermal barrier coatings (TBC) or just drilling the trench, compared to the effort of manufacturing a shaped hole design. Both him effectiveness (η) and heat transfer coefficient (h) are obtained simultaneously using the transient thermochromic liquid crystal technique. For the purpose of validation and comparison, the case without trench was performed as baseline. There are 5 holes of 10mm diameter (D) on the test plate, and a trench case with 2D width and 0.75D depth. The study is performed at a single mainstream Reynolds number of 10000 based on free-stream velocity and film hole diameter and at four different coolant-tomainstream momentum flux ratios of 0.5, 1.0, 2.0 and 4.0. The results show that film effectiveness is greatly enhanced by the trenching due to improved two dimensional nature of the film and lateral spreading. The detailed film effectiveness and heat transfer coefficient contours provide a clear understanding of the jetmainstream interactions for different hole orientations. CFD simulation using Fluent was also performed to determine the jet mainstream interactions to better understand the surface heat transfer coefficient and film effectiveness distributions.
trench hole transient heat transfer measurement film cooling liquid crystal
ZHANG Zong-wei ZHU Hui-ren WANG Meng-yuan MENG Qmg-kun
School of Power and Energy, Northwestern Polytechnical University, Xian, China
国际会议
4th International Symposium on Jet Propulsion and Power Engineering(第四届喷气推进与动力工程国际会议 ISJPPE2012)
西安
英文
279-284
2012-09-10（万方平台首次上网日期，不代表论文的发表时间）