Effects of injection on the instability of boundary layers over hypersonic configurations
Effects of injection on the instability of boundary layers over hypersonic configurations
复制标题
注入对高超声速构型边界层不稳定性的影响
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
Jeffery A. White
中科院分区：
文献类型：
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作者：
Fei Li;Meelan Choudhari;Chau;Jeffery A. White
Computations are performed to study the boundary layer instability mechanisms pertaining to hypersonic vehicles with significant ablative effects. The process of laminar-turbulent transition over vehicles with ablative heat shields can be influenced by both the out-gassing associated with surface pyrolysis and the resulting modification of surface geometry including the formation of micro-roughness. To isolate the effects of out-gassing, this paper examines the stability of canonical boundary layer flows over smooth surfaces in the presence of gas injection into the boundary layer, with an emphasis on the case of massive injection that is relevant to previous laboratory experiments. For a slender cone, the effects of strong out-gassing on the predominantly second mode instability are found to be weakly stabilizing. This new, somewhat surprising result is confirmed by computations carried out on a flat plate boundary layer at high Mach numbers. In contrast, for a blunt capsule flow dominated by first mode ...
