摘要
在求解热振动耦合问题的时候,由于耦合项的存在,使得温度场不能独立求解,大大增加了问题的复杂性。针对精确求解耦合问题的困难,从有限元法入手,运用功能强大的ANSYS分析软件,以特定板级电路模块为研究对象进行热振动耦合特性分析。在分析过程中考虑了材料参数随温度变化的非线性因素,并和不考虑热效应的振动分析结果进行了比较。通过分析与研究,得到了热应力既可以增大板级电路的固有频率,也可以减小板级电路的固有频率;在温度场的影响下,板级电路的弹性模量会降低,从而使固有频率降低,而其它材料参数对固有频率影响不一;多影响因素的综合作用下,通常会使板级电路的固有频率降低等结论。
Because of existence of coupling items, when solving thermal-vibration problems, temperature field cannot be solved independently and the complexity of problems will be increased. The paper deals with the difficulty of precise solving for coupling problems. Taking certain board level circuit module as example, its thermal-vibration coupling characteristics were analyzed by using ANASYS, software having powerful functions, and finite element methods. In analysis process, non-linear factors of material parameters' changing with temperature were viewed and comparison with the analysis results of vibration without thermal effect was also accomplished. Through analysis and study, we can get that thermal effect can either increase the intrinsic frequency of board level circuit or reduce it; with the effects of temperature field, the modulus of elasticity will be reduced that can reduce intrinsic frequency consequently. While the effects of other material parameters on intrinsic frequency are different ; with integrating effects of multi-factors, the conclusion was got that the intrinsic frequency of board level circuit will be reduced usually.
出处
《电子机械工程》
2007年第6期4-7,共4页
Electro-Mechanical Engineering
关键词
热应力
振动
固有频率
耦合
有限元
thermal effect, vibration, intrinsic frequency, coupling, finite element