DNS Study of Roughness-Induced Transition at Mach 6
DNS Study of Roughness-Induced Transition at Mach 6
复制标题
6 马赫时粗糙度引起的转变的 DNS 研究
DOI：
10.2514/6.2019-3082
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
N. Sandham
中科院分区：
文献类型：
--
作者：
J. Lefieux;E. Garnier;N. Sandham
例如，在高超音速流动中，能够在进气口上游过渡到湍流是很有用的。在目前的工作中，对以马赫数通过孤立粗糙度单元的流动进行了直接数值模拟。首先，证明了两个求解器计算涉及自由流扰动的层流和过渡流的能力。然后在没有对自由流进行声扰动的情况下进行了一系列模拟。雷诺数从 14,000 增加到 28,000，然后增加到 40,000。前两种情况在计算域内保持层流，而最后一种情况则经历了向湍流的自我维持转变。对扰动脉冲的响应表明在中间雷诺数处存在曲张模式，在最大雷诺数处存在正弦模式。
In hypersonic flows, it is useful to be able to trip the transition to turbulence upstream of air intakes for example. In the present work, direct numerical simulations have been performed of the flow past an isolated roughness element at Mach 6. First, the capability of two solvers to compute laminar and transitional flow involving freestream disturbances was demonstrated. A series of simulations was then carried out without acoustic perturbation of the freestream. The Reynolds number was increased from 14,000, to 28,000 and then to 40,000. The first two cases remain laminar within the computational domain, whereas the last case undergoes a self-sustained transition to turbulence. A response to a perturbation impulse shows the presence of a varicose mode at the intermediate Reynolds number and a sinuous mode at the largest Reynolds number.
影响因子：
2.5
作者：
J. Redford;N. Sandham;G. Roberts
通讯作者：
J. Redford;N. Sandham;G. Roberts