摘要
利用线性稳定性理论分析(LST)结合直接数值模拟(DNS)研究高超声速多孔表面边界层流动的失稳特征,分析多孔表面推迟高超声速边界层转捩的机理.在Ma=6,Re=2.0×104(参考长度为入口处边界层位移厚度)条件下获得平板边界层及不同孔隙排列情形下平板边界层的典型流动特征,并采用LST方法分析光滑平板及多孔平板扰动的增长率及累计放大率.研究表明三维顺排及错排多孔表面都可以抑制第二模扰动的发展,推迟高超声速边界层转捩,但顺排多孔表面推迟高超声速边界层转捩能力更强.
Mechanism of transition delay by porous surface in hypersonic boundary layers is investigated. Linear stability theory （LST） is adopted to analyze characteristics of instability and comparisons with direct numerical simulation （DNS） are made. Under conditions Ma =6.0, Re=2.0×10^4（ length scaled by displacement thickness of boundary layer）, typical flow characteristics are obtained for planar boundary layers with and without distributed pores. Disturbing growth rate of smooth and porous boundary layers are computed by LST. N-factor, which is regarded as a symbol of accumulated growing of disturbance, is calculated. It shows that pores prohibit growth of Mack＇s mode and therefore delay transition of hypersonic boundary layer. Sequence-distributed pores stabilize boundary-layer flow more effectively than interlace-distributed pores.
出处
《计算物理》
CSCD
北大核心
2016年第2期163-169,共7页
Chinese Journal of Computational Physics
关键词
多孔表面
直接数值模拟
线性稳定性
高超声速
porous
direct numerical simulation
linear stability analysis
hypersonic
