电子器件振动特性有限元模型参数的等效计算方法

 基于自由度缩聚技术和模态叠加原理,提出两种电子器件振动特性有限元模型参数的等效计算方法:范数极小值等效法和约束基频等效法.两种方法依据器件质量、约束基频、内部布局等特性,将具有非均匀质量和刚度分布的器件等效为均质长方形质量块,使电子器件的网格划分和数值计算大为简化.通过印制板固有特性和响应结果的对比分析,验证了等效方法的有效性和实用性.

Equivalent Computational Methods of Finite Element Model's Parameters for Vibration Analysis of Electronic Module

Based on the DOF condensation technique and the theory of mode superposition,two equivalent computational methods,the minimum norm equivalent method and constrained natural frequency equivalent method,of finite element model’s parameters for vibration analysis of electronic module are presented.The methods utilize the mass,constrained natural frequency and inner distribution of module to compute the equivalent parameters for dynamic analysis,so that an electronic module with non-uniform mass and stiffness distribution can be transformed to a block with uniform distributed mass,which greatly simplifies the meshing and solving process for numerical calculation of electronic modules’ characteristics.The validity and effectiveness of the methods are verified by comparative analysis of the inherent characteristics and dynamic response results of the whole printed circuit board.