
第23卷第8期 2015年8月
文章编号
1004-924X(2015)08-2250-08
光学精密工程
Optics and Precision Engineering
模态方法下的悬臂梁/类悬臂梁
弹性构件的动力学建模薛志鹏1,2,厉明1,贾宏光1,泽勇1
(1.中国科学院长春光学精密机械与物理研究所,吉林长春130033;
2.中国科学院大学,北京100039)
Vol.23No.8 Aug.2015
摘要:针对扇簧式起落架这一类悬臂渠弹性结构的弹性变形,提出了一种克服传统模态方法计算精度受限的模态旋转方法。首先,基于有限元理论中的小变形运动学分析推导出变形中旋转部分的表述方法。然后,总结了传统线性模态理论,提出了一种将旋转变形引人到模态坐标下动力学方程的方法,从雨在结构动力学分析中引人旋转变形的影响,使模态方法适用于旋转变形较大的情况。最后,进行了扁簧式起落架静力学仿真及实验的对比验证。结果显示:在设计载荷 100kg范围内,两种模态方法都能保证5%以内的计算精度;但在极限载荷180kg情况下,线性模态方法产生了超过 35%的计算误差,面模态旋转方法仍能够保证10%以内的计算精度。仿真过程中两种模态方法的计算步长均为1ms。结果表明:与传统的模态方法相比,提出的模态旋转方法在相对施转变形较大的情况下有更高的计算精度,同时保留了传统模态方法计算效率高的优点。
关键调:弹性变形;甚臀梁;弹性构件;模态叠加法;有限元法;扁黄式起落架
中图分类号:V279;V215.3
文献标识码:A
doi;10.3788/OPE.20152308.2250
Modalmethodbaseddynamicanalysis ofcantilevertype elastic structures
XUE Zhi-peng'-2, LI Ming', JIA Hong-guang', LUO Ze-yong(1.Changchun Institute of Optics,Fine Mechanics and Physics, ChineseAcademy of Sciences,Changchun130033,China;
2.Universityof ChineseAcademy ofSciences,Beijing100039,China)
Correspondingauthor,E-mail:.ruezhipeng1314@126.com
Abstract: For the elastic deformation of cantilever type elastic structures in a flat spring landing gear, a new modal warp method was proposed to improve the calculation precision of the traditional modal method. Firstly, the description of a rotational component in infinitesimal deformation was deduced based on the finite element theory. Then the general modal method was summarized and how to intro duce the rotational deformation into the dynamic equation in a modal coordinate was proposed. By which, the rotational deformation was introduced into the analysis of structure dynamics, so that the modal method could simulate the large bending and/or twisting deformation. Finally, the static simu-
收稿日期:2014-09-30;修订日期:2014-11-12.
基金项目:中国科学院知识创新工程国防科技创新基金资助项目(No.YYYJ-1122)