基于近场声全息的载荷识别技术及试验验证

Analysis and Verification of Load Identification Technology based on Near-field Acoustic Holography

提出1种通过辐射声测量来识别激励源的基于近场声全息的载荷识别技术。针对所研究的圆筒结构,通过测量激励产生的辐射声场,使用近场声全息的声场理论建立内部声等效源,进而用基于等效源的近场声全息方法重构结构表面振速。将振速换算成法向加速度对激励进行识别,并与由力传感器直接测得的力谱进行比较,结果显示主要峰值频率处激励力的辨识误差均在5 d B以下,满足工程应用要求。

A load recognition technique based on near-field acoustic holography was proposed to identify the excitation source through the radiation acoustic measurement. For a cylinder structure, the radiation acoustic field generated by excitation was measured and the internal acoustic equivalent source was constructed by the sound field theory of the nearfield acoustical holography. Then, the surface vibration velocity was reconstructed based on the equivalent source of the nearfield acoustic holography. By translating the surface velocity to normal acceleration, the excitation force was identified.Compared with the results measured by the force sensor, the identification error of the excitation force at the main peak frequency is found to be below 5 d B, which meets the engineering application requirements.