高超声速边界层中粗糙元强制转捩的机理

项目名称： 高超声速边界层中粗糙元强制转捩的机理

项目编号： No.11472189

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 董明

作者单位： 天津大学

项目金额： 86万元

中文摘要： 由大粗糙元引起的高超声速边界层强制转捩问题，是当前航天领域，特别是高超声速吸气式发动机研制者高度关注的流体力学问题。本项目以实验数据为参照，对扰动在粗糙元尾迹流场中增长并触发转捩的整个过程进行数值模拟，并借助前期对bypass转捩的研究成果，从稳定性观点出发，分析粗糙元强制转捩的breakdown过程的关键机理。成果除了有科学价值外，对高超声速吸气式发动机进气道的粗糙带设计也有直接的帮助。

中文关键词： 线性稳定性理论；直接数值模拟；高超声速；边界层转捩；二维全局不稳定性

英文摘要： Roughness-induced transition in hypersonic boundary layer is a problem of fluid mechanics highly concerned by people in aero-space industry, especially by those who are working on hypersonic scramjet engine. In this program, based on the experimental data, the whole process of disturbances growing in the wake flow of the roughness elements and further triggering transition is studied by numerical simulation, and from the previous study on bypass transition, by using stability theory, the key mechanism of the breakdown process on roughness-induced transition is analyzed. The results would have not only scientific value, but can also by directly applied to the research and development of hypersonic scramjet engine.

英文关键词： linear stability theory;direct numerical simulation;hypersonic;boundary layer transition;bi-global instability