Dynamic Buckling of Functionally Graded Cylindrical Shells under Axial Loading
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摘要: 基于Donnell壳体理论和经典板壳理论,利用Hamilton变分原理得到轴向荷载作用下材料属性呈幂律分布的功能梯度材料圆柱壳的动力屈曲控制方程。根据圆柱壳周向连续性设出径向位移的函数表达,利用分离变量法求解得到功能梯度材料圆柱壳在轴向荷载作用下的动力屈曲临界荷载的解析表达式和屈曲解。利用MATLAB软件编程计算,讨论了径厚比、梯度指数、环向模态数、轴向模态数等对功能梯度材料圆柱壳动力屈曲临界荷载的影响。结果表明:圆柱壳的临界荷载随临界长度的增加而减小;冲击端为夹支的临界荷载比冲击端为简支的临界荷载大,说明约束条件对临界荷载有较大影响;圆柱壳的临界荷载随着模态数的增加而增大,说明临界荷载越大,高阶模态越易被激发;屈曲模态图随着模态数的增加而复杂化。
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关键词:
- 功能梯度材料 /
- 屈曲临界荷载 /
- 圆柱壳 /
- Hamilton原理 /
- 模态数
Abstract: Based on the Donnell shell theory and classical shell theory, we established the dynamic buckling governing equation of functionally graded cylindrical shell under axial load using Hamilton principle.According to the expression of the radial displacement based on the circumferential continuity of cylindrical shell, we also obtained the dynamic buckling critical load expression and the buckling solution of functionally graded cylindrical shell under axial loading using the separation variable method.Using MATLAB, we performed the numerical analysis of functionally graded cylindrical shells, and discussed the influence of the diameter-thickness ratio, the gradient index, the number of circumferential mode and axial mode on the critical load of dynamic buckling.The results show that the critical load of cylindrical shells decreases with the increase of the critical length.The constraint conditions have effects on the critical load, and the critical load of the clamped edges is higher than that of the simple support.Moreover, the critical load of cylindrical shells grows as the modal number increases, indicating that the higher the critical load is, the easier the high-stage mode excites.The dynamic buckling modal diagram becomes more complicated as the modal number increases. -
表 1 材料参数
Table 1. Material parameters
Material E/GPa ρ/(g·cm-3) μ Ceramic 385 3.96 0.230 Ti 109 4.54 0.410 Fe 155 7.86 0.291 Cu 119 8.96 0.326 -
[1] KOIZUMI M. The concept of FGM//ZHAI P C, JIANG C R, ZHANG Q J, et al. Ceramic Transactions: Functionally Gradient Materials. Westerville, OH: The American Ceramic Society, 1993, 34: 3-10. [2] LOY C T, LAM K Y, REDDY J N.Vibration of functionally graded cylindrical shells[J].International Journal of Mechanical Sciences, 1999, 41(3):309-324. doi: 10.1016/S0020-7403(98)00054-X [3] SURESH S, MORTENSEN A.Fundamentals of functionally graded materials[M].The Institute of Materials, 1998:18. [4] ELLINAS C P, CROLL J G A.Elastic-plastic buckling design of cylindrical shells subject to combined axial compression and pressure loading[J].International Journal of Solids and Structures, 1986, 22(9):1007-1017. doi: 10.1016/0020-7683(86)90033-8 [5] VAZIRI A, ESTEKANCHI H E.Buckling of cracked cylindrical thin shells under combined internal pressure and axial compression[J].Thin-Walled Structures, 2006, 44(2):141-151. doi: 10.1016/j.tws.2006.02.004 [6] LATIFI M, FARHATNIA F, KADKHODAEI M.Buckling analysis of rectangular functionally graded plates under various edge conditions using Fourier series expansion[J].European Journal of Mechanics-A/Solids, 2013, 41(11):16-27. http://linkinghub.elsevier.com/retrieve/pii/S0997753813000107 [7] MANTARI J L, MONGE J C.Buckling, free vibration and bending analysis of functionally graded sandwich plates based on an optimized hyperbolic unified formulation[J].International Journal of Mechanical Sciences, 2016, 119:170-186. doi: 10.1016/j.ijmecsci.2016.10.015 [8] LI S R, BATRA R C.Buckling of axially compressed thin cylindrical shells with functionally graded middle layer[J].Thin-Walled Structures, 2006, 44(10):1039-1047. doi: 10.1016/j.tws.2006.10.006 [9] BENI T Y, MEHRALIAN F, ZEIGHAMPOUR H.The modified couple stress functionally graded cylindrical thin shell formulation[J].Mechanics of Advanced Materials and Structures, 2016, 23(7):791-801. doi: 10.1080/15376494.2015.1029167 [10] KARGARNOVIN M H, HASHEMI M.Buckling analysis of multilayered functionally graded composite cylindrical shells//Applied Mechanics and Materials.Trans Tech Publications, 2012, 108:74-79. http://adsabs.harvard.edu/abs/2011AMM...108...74K [11] SOFIYEV A, DENIZ A, MECITOGLU Z, et al.Buckling of shear deformable functionally graded orthotropic cylindrical shells under a lateral pressure[J].Acta Physica Polonica A, 2015, 127(4):907-909. doi: 10.12693/APhysPolA.127.907 [12] KHAZAEINEJAD P, NAJAFIZADEH M M, JENABI J, et al.On the buckling of functionally graded cylindrical shells under combined external pressure and axial compression[J].Journal of Pressure Vessel Technology, 2010, 132(6):064501. doi: 10.1115/1.4001659 [13] KHALILI S M R, MALEKZADEH K, DAVAR A.Dynamic response of functionally graded circular cylindrical shells//Advanced Materials Research.Trans Tech Publications, 2008, 47:608-611. http://www.scientific.net/AMR.47-50.608 [14] ALASHTI R A, AHMADI S A.Buckling analysis of functionally graded thick cylindrical shells with variable thickness using DQM[J].Arabian Journal for Science and Engineering, 2014, 39(11):8121-8133. doi: 10.1007/s13369-014-1356-4 [15] 沈观林, 胡更开, 刘彬.复合材料力学[M].2版.北京:清华大学出版社, 2013. [16] 孟豪, 韩志军, 路国运.复合材料圆柱壳非轴对称动力屈曲[J].振动与冲击, 2017, 36(11):27-30. http://d.old.wanfangdata.com.cn/Periodical/zdycj201711005MENG H, HAN Z J, LU G Y.Non-axisymmetric dynamic buckling of composite cylindrical shells[J].Journal of Vibration and Shock, 2017, 36(11):27-30. http://d.old.wanfangdata.com.cn/Periodical/zdycj201711005 [17] WANG J Q, HAN Z J, LU G Y.Dynamic buckling of elastic cylindrical shells under axial step load[J].Applied Mechanics & Materials, 2015, 751:182-188. http://www.scientific.net/AMM.751.182 [18] 韩志军.直杆的撞击屈曲及其应力波效应的实验和理论研究.太原:太原理工大学, 2005. [19] YU X H, HAN Z J, KANG Z Y, et al. Computer simulation of cylindrical shell penetrated by rigid projectile//Applied Mechanics and Materials. Trans Tech Publications, 2012, 152: 594-598. [20] 李楠, 韩志军, 路国运.基于里兹法研究复合材料层合板的动力屈曲问题[J].振动与冲击, 2016, 35(10):180-184. http://d.old.wanfangdata.com.cn/Periodical/zdycj201610029LI N, HAN Z J, LU G Y.Dynamic buckling analysis of laminated composite plates by using Ritz method[J].Journal of Vibration and Shock, 2016, 35(10):180-184. http://d.old.wanfangdata.com.cn/Periodical/zdycj201610029