首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   8篇
  完全免费   1篇
  力学   9篇
  2011年   1篇
  2010年   1篇
  2009年   2篇
  2007年   2篇
  2006年   2篇
  2005年   1篇
排序方式: 共有9条查询结果,搜索用时 968 毫秒
1
1.
柴油机气缸盖多场耦合三维有限元分析   总被引:2,自引:0,他引:2  
气缸盖是柴油机重要的零部件之一,在工作过程中承受着高温与交变的机械载荷,其强度是设计人员非常关心的问题。本文利用有限元分析软件MSC.MARC,对某柴油机气缸盖进行三维非线性有限元分析,在考虑各组件接触关系的基础上,计算了气缸盖在螺钉的预紧力、热载荷、爆发压力多场耦合作用下的应力场和位移场分布情况,为改进设计提供参考。  相似文献
2.
In order to study the multi-field coupling mechanical behavior of the simply-supported conductive rectangular thin plate under the condition of an externally lateral strong impulsive magnetic field, that is the dynamic buckling phenomenon of the thin plates in the effect of the magnetic volume forces produced by the interaction between the eddy current and the magnetic fields, a FEM analysis program is developed to characterize the phenomena of magnetuelastic buckling and instability of the plates. The critical values of magnetic field for the three different initial vibrating modes are obtained, with a detailed discussion made on the effects of the length-thickness ratio a/h of the plate and the length-width ratio a/b as well as the impulse parameterτon the critical value BOcr of the applied magnetic field.  相似文献
3.
Research of air-cushion isolation effects on high arch dam reservoir   总被引:1,自引:0,他引:1  
A three-dimensional (3D) finite element model of air-cushion isolated arch dam is presented with the nonlinear gas-liquid-solid multi-field dynamic coupling effect taken into account.In this model,the displacement formulation in Lagrange method,pressure formulation in Euler method,nonlinear contact model based on Coulomb friction law are applied to the air-cushion,reservoir and contraction joint domain,respectively.The dynamic response of Jinping I arch dam with a height of 305 m is analyzed using the seismic records of the Wenchuan Earthquake in 2008.Numerical results show that the air-cushion isolation reduces significantly the hydrodynamic pressure as well as the opening width for the contraction joints of high arch dam.  相似文献
4.
Liquid crystal elastomer is a kind of anisotropic polymeric material, with complicated micro-structures and thermo-order-mechanical coupling behaviors. In this paper, we propose a method to systematically model these coupling behaviors. We derive the constitutive model in full tensor structure according to the Clausius-Duhem inequality. Two of the constitutive equations represent the mechanical equilibrium and the other two represent the phase equilibrium. Choosing the total free energy as the combination of the neo-classical free energy and the Landau-de Gennes nematic free energy, we obtain the Cauchy stress-deformation gradient relation and the order-mechanical coupling equations. We find the analytical homogeneous solutions of the deformation for the typical mechanical loadings, such as uniaxial stretch, and simple shear in any directions. We also compare the compression behavior of prolate liquid crystal elastomers with the stretch behavior of oblate liquid crystal elastomers. As a result, the stress, strain, temperature, order parameter, biaxiality and the direction of the director of liquid crystal elastomers couple with each other. When the prolate liquid crystal elastomer sample is stretched in the direction parallel to its director, the deviatoric stress makes the mesogens more order and increase the transition temperature. When the sample is sheared or stretched in the direction non-parallel to the director, the director of the liquid crystal elastomer will rotate, and the biaxiality will be induced. Because of the order-mechanical coupling, under infinitesimal deformation, liquid crystal elastomer has anisotropic Young’s modulus and zero shear modulus in the direction parallel or perpendicular to the director. While for the oblate liquid crystal elastomers, the stretch parallel to the director will cause the rotation of the director and induce the biaxiality.  相似文献
5.
孙晋美  郭万林 《力学进展》2006,36(4):536-552
围绕包括扫描探针显微镜在内的各种探针技术下核酸、蛋白质等生物分子及生物材料的生物力学与力-电耦合实验研究,较系统地总结了分子层次或纳米尺度下生物分子和材料的力学性能的扫描探针显微镜、光镊、磁镊等探针技术的实验研究方法和主要进展,进而探讨了在“针尖”这个极小、极特殊环境下的分子生物物理力学研究状况.通过介绍借助探针技术研究相关生物物质的结构、力学、电学等性能以及提出的一些理论模型,指出探针技术在生物分子(包括遗传物质和蛋白质)力学性能、纳米生物材料结构及分子仿生等研究中的广泛意义.提出多场耦合作用下的针尖的生物物理力学研究必定是将来研究的重点;将针尖的分子生物力学的物理实验研究与分子物理力学理论、计算科学相结合,发展分子物理力学虚拟实验技术是本领域的一个重要发展方向.  相似文献
6.
A theoretical model is suggested to mathematically describe the effect of thermal diffusion from a sand-bed on evolution of a wind-blown sand flow.An upward wind field is engendered by the thermal diffusion and the coupling interaction among the horizontal and upward wind flow,saltating grains,and a kind of electrostatic force exerted on the grains are considered in this theoretical model.The numerical results show that the effect of the thermal diffusion on the evolution process of wind-blown grain flow is quite obvious and very similar to the effect of the electrostatic force on the evolution.Not only the time for the entire system to reach a steady state(called the duration time),the transport rate of grains,the mass-flux profiles and the trajectory of saltating grains are affected by the thermal diffusion and the electrostatic force exerted on saltating grains, but also the wind profiles and the temperature profiles at the steady state are affected by the wind-blown sand flow.  相似文献
7.
陈浩然  任明法  赵伟 《力学进展》2007,37(2):233-245
综述了复合材料缠绕壳体结构成型和使用过程的多场分析的国内外近代研究进展,其中包括:缠绕成型工艺,固化工艺,超压工艺,使用过程中的应力分析,低速冲击损伤等相关问题.在此基础上,着重介绍了倍受航天界所关注的含薄壁金属内衬的复合材料缠绕容器的成型工艺和低速冲击损伤一体化研究工作,并提出了该领域今后还需进一步研究的内容.  相似文献
8.
Based on the generalized variational principle of magneto-thermo-elasticity of the ferromagnetic elastic medium, a nonlinear coupling theoretical modeling for a ferromagnetic thin shell is developed. All governing equations and boundary conditions for the ferromagnetic shell are obtained from the variational manipulations on the magnetic scalar potential, temperature and the elastic displacement related to the total energy functional. The multi-field couplings and geometrical nonlinearity of the ferromagnetic thin shell are taken into account in the modeling. The general modeling can be further deduced to existing models of the magneto-elasticity and the thermo-elasticity of a ferromagnetic shell and magneto-thermo-elasticity of a ferromagnetic plate, which axe coincident with the ones in literature.  相似文献
9.
Based on the generalized variational principle of magneto-thermo-elasticity of the ferromagnetic elastic medium,a nonlinear coupling theoretical modeling for a ferromagnetic thin shell is developed.All governing equations and boundary conditions for the ferromagnetic shell are obtained from the variational manipulations on the magnetic scalar potential,temperature and the elastic displacement related to the total energy functional.The multi-field couplings and geometrical nonlinearity of the ferromagnetic t...  相似文献
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号