基于优化模型的结构声学耦合界面载荷传递算法

An optimization-based algorithm for data exchange on the interface between the structure and the acoustic medium

针对结构声学耦合系统的界面载荷传递问题,提出了一种基于约束最优化模型的局部参数插值算法。耦合界面处结构和流体单元表面坐标通过各自的形状函数进行插值,把界面载荷在互不匹配的网格节点间的传递问题转化为一个点到用自然坐标表示的有限边界曲面的最小距离问题,以便利用成熟稳定的优化算法对其进行高效求解。与已有方法相比,该算法在耦合界面单元为曲面的情况下仍能保持较高的计算精度。本文给出的数值算例验证了本算法的有效性和可靠性。

An algorithm based on parameter interpolation and optimization model is developed for solving the problem of load transformation on the interface of the structural-acoustic coupling system. The element surfaces of the structure and the fluid on the interface are interpolated by shape functions, respec- tively. The key of the proposed approach for load transformation is to handle an optimization problem of minimizing the distance from the grid point of one mesh （e. g. the structural mesh） to the corresponding element surface of another mesh （e. g. the acoustic mesh） on the interface. The model may be solved u- sing the well-developed optimization algorithm in a very efficient manner. In comparison with the previ- ous methods, the proposed method maintains high precision even for the case that the element surfaces of the coupling interface have pronounced curvature. The algorithm is implemented in computer and is veri- fled by numerical examples.