摘要
应用全局弱式无网格方法求解消声器的横向模态,使用径向基函数点插值法离散本征方程,使用伽辽金加权残数法进行数值积分。分别应用全局弱式无网格方法计算了圆形截面,不规则截面以及含有穿孔截面的本征值和本征向量,计算结果与解析方法和二维有限元方法计算结果吻合较好,并且与二维有限元方法相比,全局弱式无网格方法比较节省计算时间。进而分析了支持域的尺寸以及径向基函数中形状参数对计算精度的影响。
The transverse modes of silencers are extracted by using the global weak-form mesh-free method(MFM).The radial base-function point interpolation method is used for dispersing the eigenvalue equations and the Galerkin method is used for numerical integration. Utilizing the global weak-form mesh-free method, the eigenvalues and eigenvectors of the model with circular section, irregular section and perforated section are calculated respectively. Results of computation are in good agreement with those of analytical solution and 2 D finite element solution. Compared with 2 D finite element method,the global weak-form mesh-free method has less computer-time consuming. Additionally, the effects of size of support domain and shape parameters of the radial basis functions on the calculation accuracy are evaluated.
引文
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