基于FEM-PIM计及热效应的统计能量分析  

Statistical energy analysis considering thermal effect based on FEM-PIM

作　　者：陈强[1,2] 张鹏[1,2] 李彦斌[3] 吴邵庆[1,2] 费庆国[1,2] 

机构地区：[1]东南大学土木工程学院工程力学系,南京210096 [2]东南大学江苏省工程力学分析重点实验室,南京210096 [3]东南大学机械工程学院,南京211189

出　　处：《航空动力学报》2017年第6期1366-1374,共9页Journal of Aerospace Power

基　　金：国家自然科学基金(11572086;11402052);教育部新世纪优秀人才支持计划(NCET-11-0086);江苏省自然科学基金(BK20140616)

摘　　要：结合有限元法(FEM)和模态坐标系下计及热效应的功率输入法(PIM),给出一种热环境下适用于复杂结构的统计能量分析方法.以各边简支的L型折板为研究对象,开展雨流载荷作用下的数值模拟验证方法的准确性.开展3种工况条件下热效应对统计能量分析参数的影响研究:(1)仅考虑热效应引起的材料力学性能变化;(2)仅考虑热应力引起的附加刚度效应;(3)同时考虑考虑两者影响.结果表明:温升影响材料力学性能的同时会导致耦合损耗因子减小,但对内损耗因子的影响不大;热应力引起的附加刚度效应对内损耗因子和耦合损耗因子的影响较大,两者均随温度的升高而逐渐减小;同时考虑两者影响时,热应力对统计能量分析参数的影响占主导地位,内损耗因子和耦合损耗因子均随温度的升高而逐渐减小;模态密度与温度的变化趋势基本一致.With the combination of the finite element method （FEM） and the power injection method （PIM） under modal coordinate considering thermal effect,a statistical energy analysis method applicable of vibration analysis of complex structures under thermal environment was presented.A simply supported L-shaped folded plate under rain on the roof excitation was studied and the accuracy of proposed method was verified with numerical examples.The influence of thermal effect on the parameters in statistical energy analysis was investigated under three cases：（1） only the material properties were affected by the thermal effect;（2） only the additional stiffness due to thermal stresses was considered;（3） both （1） and （2） were considered.Results showed that the increasing temperature changed the material properties and decreasd the value of coupling loss factor,but had little influence on internal loss factor.The thermal stresses had great influence on the parameters in statistical energy analysis,the increasing temperature decreasd both internal loss factor and coupling loss factor.When both （1） and （2） were considered,the influence of thermal stresses was dominant,the internal loss factor and the coupling loss factor gradually decreased with the increase of temperature.Similar trend was found between the change of modal density and temperature.

关 键 词：统计能量分析 热效应 功率输入法 内损耗因子 耦合损耗因子 

分 类 号：V414.8[航空宇航科学与技术—航空宇航推进理论与工程] O32[理学—一般力学与力学基础]