Improvement on shaped-hole film cooling effectiveness by integrating upstream sand-dune-shaped ramps

• 来源期刊: 中国航空学报（英文版）
• 年，卷（期）: 2021,（4）
• 页码范围: 42-55
• 页数: 14页
• 语种: 英文

摘要

A numerical investigation and experimental validation is performed to address deeper insights into the combined effect of shaped holes and Sand-Dune-shaped upstream Ramp (SDR)on enhancing the film cooling effectiveness,under a wide blowing ratio range (M =0.25-1.5).Three kinds of holes (Cylindrical Hole (CH),Fan-Shaped Hole (FSH),and Crater-Shaped Hole (CSH)) are taken into consideration.The SDR shows an inherent affecting mechanism on the mutual interaction of jet-in-crossflow.It aggravates the lateral spreading of cooling jet and thus improves the film cooling uniformity significantly,regardless of film-hole shape and blowing ratio.When the blowing ratio is beyond 1.0,the combined effect of shaped holes and SDR on improving film cooling effectiveness behaves more significantly.It is suggested that FSH-SDR is a most favorable film cooling scheme.For FSH-SDR case,the spatially-averaged film cooling effectiveness is increased monotonously with the increase of blowing ratio,among the present bowing ratio range.