针对微机电系统多物理场耦合效应有限元解析所遇到的难题,应用元胞自动机的思想来解析其热-力耦合场.以典型微结构中的平板结构为研究对象,根据应变能守恒,将连续性单元转化为米字形桁架结构,并建立元胞空间;从简单的二力杆热力分析出发,推导热应力的局部规则,建立了该平板结构的元胞自动机模型,对热弹性力学中的平面应力问题进行了分析.从实例解析出发,对热应力产生的不同情况进行了模拟分析,验证了所建热-力耦合解析方法的可行性和算法的效率.该解析算法也适用于力载荷或位移载荷,为微结构多物理场耦合解析提供了有效的解析方向.
To resolve impacts on microelectromechanicl devices and systems (MEMS) multiple-physical coupling effects via finite-element analytic methods, the cellular automata is applied to analyze thermomechanical coupling fields. Pertaining to the strain energy conservation, a typical MEMS plate is employed as a cellular space to transfer continuum elements into joist truss structures. By analyzing thermal stresses on a dual-force rod, a local rule is deduced in terms of the plate cellular automata. In this process, the plain stress is analyzed using thermoelastic mechanics. To verify the feasibility and algorithmic efficiency of thermomechanical-coupling analytic method, thermal stresses are experimentally simulated. Eventually, it is found that this algorithm can be adapted to force and displacement loadings for analyzing the MEMS multiple-physical coupling.