任意声场中非规则形状Rayleigh散射体的声辐射力研究
Research on acoustic radiation force of an irregularly shaped Rayleigh scatterer in an arbitrary sound field
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摘要: 为满足声辐射力更广泛的应用,克服传统辐射力理论仅适合简单理想声场及规则形状散射体的局限性,建立丁任意入射声场中非规则形状Rayleigh散射体的声辐射力计算理论。针对任意声场中流体质点沿曲线轨迹振动以及非规则散射体空间姿态随机取向的特点,在散射场计算中同时计入散射体质心平移与姿态转动的影响,得到了更为普适性的散射场速度势函数。在此基础上,推导出适于任意声场中非规则散射体的声辐射力计算公式。实例研究表明,本文方法不仅完全满足简单声场规则散射体的辐射力计算,而且还适合于任意声场非规则散射体辐射力的应用,规则散射体的计算结果与传统方法完全一致,而对于非规则散射体证实了其旋转角速度不为零,且声辐射力随姿态不同而变化。Abstract: For extending the application fields of the acoustic radiation force and breaching the limitations on the type of the incident sound field and the geometrical shape of the scatterer in the existing theories,a generalized theory which is suitable for the calculation of the acoustic radiation force on an irregularly shaped Rayleigh scatterer in an arbitrary sound field is established.By concerning the curvilinear trajectory of the fluid particle's movement and the stochastic orientation of the scatterer's attitude,the typical theory for Rayleigh scattering is extended to account the translation and rotation movement of the scatterer induced by the first order stress of the sound field.Based on the velocity potential for the scattered field,calculating formula of the radiation force on an irregular scatterer in an arbitrary sound field is derived.Case studies show that for a regularly shaped scatterer in a simple type sound field the results using the method in this work are consistent with that in the literature,for irregular scatterers the angular speed is nonzero and the radiation force changes with the variance of the spatial attitude.