流激开孔和空腔结构耦合振动噪声试验研究

摘要

In order to discuss opening and cavity shear flow-induced vibration and structural coupling resonance, experiments of opening and cavity shear flow-induced vibration and structural noise control are carried out. The impact of the opening size, flow velocity and cavity thickness on shear oscillation noise, self-noise in the cavity and radiated noise are analyzed. The results show that the empirical formula of the opening shear oscillation in air is also applicable to the condition underwater, which the shear oscillation and amplitude of modal frequencies are directly proportional to the flow velocity; in case that no coupling resonance occurs, the thickness of the cavity wall will bring slight influence on the amplitude of the shear oscillation, but not on the mode frequencies; also the coupling of shear oscillatory mode and cavity wall mode show dramatic coupling resonance under certain conditions, and leads to self-noise and acoustic radiation. The findings supply useful exploration and technical support concerning the application of opening and cavity structural noise control measures.%[目的]为了研究流激开孔和空腔结构耦合振动噪声,[方法]采用模型试验方法,通过改变孔腔开口大小、来流速度和腔体厚度等,分析其对剪切振荡噪声、腔体自噪声和辐射噪声的影响.[结果]研究表明:空气中的开孔剪切振荡经验公式同样适用于水中情况,剪切振荡频率和剪切振荡量级均与来流速度呈正比;未发生开孔和空腔耦合共振时,腔体壁面刚度仅略微影响剪切振荡量级,而不影响剪切振荡模态频率;在特定的开口和流速下,剪切振荡模态与弹性腔壁模态耦合,产生剧烈的谐频共振以及极大的自噪声与辐射噪声.[结论]研究结果可为潜艇舷外开孔和附近结构设计,以及孔腔结构噪声控制提供有益的探索和技术支撑.