基于FEM-DMF的耦合损耗因子预示精度分析  

Analysis on predictive accuracy of coupling loss factor based on FEM-DMF

作　　者：王攀 陈强 戴元伦[3] 费庆国 张鹏[1,2] 李彦斌[2,4] 

机构地区：[1]东南大学土木工程学院,南京210096 [2]东南大学空天机械动力学研究所,南京211189 [3]中国船舶重工集团公司第701研究所,武汉430064 [4]东南大学机械工程学院,南京211189

出　　处：《东南大学学报（自然科学版）》2018年第1期125-131,共7页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金资助项目(11572086,11402052); 江苏省自然科学基金资助项目(BK20170656,BK20170022); 江苏省研究生科研与实践创新计划资助项目(KYCX17_0054)

摘　　要：基于有限元-双模态方程法(FEM-DMF)开展结构耦合损耗因子的预示精度研究.以典型L型耦合板为研究对象,通过与有限元-功率输入法(FEM-PIM)对比,深入研究了分析频带、子系统刚度比和结构阻尼对FEM-DMF方法预示耦合损耗因子精度的影响.以L型耦合加筋板为研究对象,验证FEM-DMF方法在复杂结构中的适用性.结果表明:在满足模态能量均一化假设的频带内,随着L型耦合板的子系统刚度比和结构阻尼的增大,FEM-DMF方法的预示精度不断提高;且随着结构阻尼的增大,满足耦合损耗因子预示精度的临界刚度比逐渐减小;对于L型耦合加筋板,在满足模态能量均一化假设的频带内,基于FEM-DMF方法预示的耦合损耗因子误差小于1 d B;而与FEM-PIM相比,FEM-DM F方法的计算效率提高了87.5%,从而说明FEM-DM F方法在其适用范围内能够准确高效地预示复杂结构的耦合损耗因子.The predictive accuracy of a structural coupling loss factor is investigated based on the finite element-dual modal formulation（ FEM-DM F） method. Taking the typical L-shaped plate as a research object,compared w ith the finite element-pow er injection method（ FEM-PIM）,the effects of frequency band,subsystem stiffness ratio and structural damping on the predictive accuracy of the coupling loss factor of FEM-DM F method are studied. A L-shaped stiffened plate is used to verify the applicability of FEM-DM F method on the complex structure. Results show that in the frequency band satisfying the assumption of modal energy homogenization,the accuracy of FEM-DM F method for the prediction of the coupling loss factor is improved with the increase of the stiffness ratio and the structural damping of L-shaped plate subsystems. The critical stiffness ratio of subsystems satisfying the accuracy of the coupling loss factor decreases with the increase of structural damping. For L-shaped stiffened plates,the error of the coupling loss factor predicted by the FEM-DM F method is less than 1 d B in the frequency band satisfying the assumption of modal energy homogenization. Compared with FEM-PIM,the computational efficiency of FEM-DM F method is increased by 87. 5%,indicating that FEM-DM F method can predict the coupling loss factor of complex structure accurately and efficiently in the applicable scope.

关 键 词：耦合损耗因子 刚度比 结构阻尼 双模态方程 加筋板 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3