摘要
提出了一种求解结构声辐射问题的Burton-Miller改进型边界积分方程,利用拉普拉斯方程的特性对传统边界积分方程及其法向偏导方程进行处理,转化其中与频率相关的高阶奇异积分项和柯西型积分项分别为弱奇异积分项和不含奇异性的积分项;进一步联立求解结构内外拉普拉斯问题下的边界积分方程,将与频率无关的高阶奇异积分项和柯西型积分项转化为弱奇异积分乘积的形式,以保证计算的精度.以脉动球源和横向振动球源为例,将所得结果与传统边界积分方程相比较,表明该方法不仅可以保证全波数范围内解的唯一性,且具有很高的计算精度.
A modified Burton-Miller improved boundary integral equation for structural acoustic radiation problem was proposed.The traditional boundary integral equations and its normal derivation were dealt with the properties of the Laplace equation,and the high-order singular integration and Cauchy-type integration in the equations associated with frequency were respectively transformed into weak singular integration and non-singular integration.Furthermore,by solving the boundary integral equation in the form of Laplace problem inside and outside the structure,the frequency-independent high-order singular integral terms and the Cauchy integral terms can be transformed into the product of weak-singular integrals to ensure the accuracy.Taking the pulsating sphere source and the lateral vibration sphere as examples,the results show that the method can not only guarantee the uniqueness of solutions in the range of full wave number,but also has high computational accuracy compared with the traditional boundary integral equation.
引文
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