摘要
以声学超表面为研究对象,采用线性稳定性理论,研究了声学超表面导纳幅值与相位对超声速边界层内第一模态的影响。研究结果表明,当导纳相位θ接近0.5π时,第一模态趋于稳定;与此同时,在一定范围内导纳幅值的增大能够增强第一模态的稳定性,但超出该范围后幅值的增大会激发第一模态。在此基础上,采用反向设计的思想,通过对声学超表面微结构的几何尺寸进行优化设计,实现其在马赫数为4的平板边界层流动中抑制第一模态的目标。
Taking the acoustic metasurfaces as the research object,the influence of the admittance amplitude and phase on the first mode in a high-speed boundary layer are analyzed using linear stability theory.It showns that the first mode is damped when the admittance phaseθtends to 0.5π.Meanwhile,the increase of amplitude in a certain range can enhance the stability of the first mode,while amplitude out of the range may amplify the first mode.Based on the requirements of the admittance phase and amplitude for the suppression of the first mode,the reverse design strategy is used for the structural design of the acoustic metasurfaces to satisfy the target which stabilizes the first mode on the flat plate boundary layer with the freestream Mach number 4.
作者
赵瑞
严昊
席柯
温志湧
Zhao Rui;Yan Hao;Xi Ke;Wen Zhiyong(Beijing Institute of Technology,Beijing 100081,China;Research Institute of Navigation and Control Technology,Beijing 100089,China;The Hong Kong Polytechnic University,Kowloon 999077,China)
出处
《航空科学技术》
2020年第11期104-112,共9页
Aeronautical Science & Technology
基金
国家自然科学基金(11872116,11991030,11991033)。
关键词
声学超表面
第一模态
线性稳定性分析
边界层转捩
超声速流动
acoustic metasurfaces
first mode
linear stability analysis
boundary-layer transition
supersonic flow
