【摘 要】
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This paper presents the results of a numerical study of the effects of swirling flow in cool-ant jets on film cooling performance.Some combined-hole designs with swirling coolant flow enter-ing the delivery hole are proposed and analyzed.Adiabatic film co
【机 构】
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School of Mechanical Engineering,Northwestern Polytechnical University,Xi’an 710072,China;Research &
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This paper presents the results of a numerical study of the effects of swirling flow in cool-ant jets on film cooling performance.Some combined-hole designs with swirling coolant flow enter-ing the delivery hole are proposed and analyzed.Adiabatic film cooling effectiveness values for cases with various blowing ratios are compared.Detailed flow structures and underlying mecha-nisms are discussed.The results show that film cooling effectiveness is improved with jet swirl at high blowing ratios,and that swirl strength has significant influence on film cooling performance.Combined-hole designs can further improve film cooling performance using swirling jets due to mixing of coolant flows and interaction of vortices.The largest improvements of area-averaged film cooling effectiveness for a single-hole swirl case and a combined-hole swirl case over corresponding non-swirling case results are 157％ and 173％,respectively.
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