查询词典 strain tensor

To establish the constitutive equation of material, the metric tensor for stress , strain and their transformation equations between different configurations are derived, and basic theory of finite deformation as well as elasto-plastic deformation criterion are studied. By analyzing the applicability of different element models, four-node quadrilateral degenerated Mindlin isoparametric element is adopted because of its good versatility, and the element stiffness matrix is derived. The static implicit elasto-plastic finite element equation for complex skin stretch-forming is put forward based on Updated Langrange formulation.

本文首先系统地阐述了有限变形的相关基本理论，针对板料成形建立了应力应变度量张量及其相应的转换关系；介绍了材料的屈服准则、塑性变形强化规律、塑性流动规律以及加、卸载准则，并在此基础上建立了有限变形各向异性弹塑性本构方程；对板料成形的单元模型进行了分析，针对飞机蒙皮零件特点，采用通用性强的四节点四边形退化Mindlin等参壳单元进行成形模拟，并导出其单元刚度矩阵的具体形式；基于以上研究，以逐级更新Langrange描述的持续虚功率原理为基础，建立了率形式的复杂蒙皮拉形过程静态隐式弹塑性有限元方程。

In this thesis, we provide myocardial fiber architecture and mechanical function non-invasively and in vivo by using cardiac diffusion tensor imaging and strain rate magnetic resonance imaging in beating heart.

本研究的重点是利用扩散张量与应变速率磁振造影技术於活的且跳动的心脏上，提供了非侵犯性（non-invasive）、活体上分析心脏的心肌纤维结构与功能的影像技术。

The results show that the delay angle between stress deviation and strain increment tensor firstly exhibits a large variation range, and then drop to saturation as the plastic deformation processes.

结果表明：应力矢量和应变增量矢量之间的滞迟角在循环变形初期表现为较大的变化幅度，随着塑性变形的进行，变化幅度逐渐减小，并趋于稳定。

One foot sensor, being a tensometer membrane, was fixed to the rubber, spherical end of the leg, and the other, a trunk tensor, being strain gauge bridge (Fig. 4), was placed between a leg and the trunk.

一个脚的传感器，作为拉伸应变片，被固定在橡皮上贴在腿的球状端；另外，躯干的张量应变片做成应变桥（图4），贴在腿和躯干之间。

MSG and SG theory are generalized to compressible material based on a new decomposition of strain gradient tensor, because the original MSG and SG theories are only suitable for incompressible materials.

因为原先的MSG和SG理论只能适用于不可压缩材料，所以在重新分解应变梯度张量的基础上，本文把MSG和SG理论拓展到可压缩材料。

MSG and SG theory are generalized to compressible material based on a newdecomposition of strain gradient tensor,because the original MSG and SG theoriesare only suitable for incompressible materials.

因为原先的MSG和SG理论只能适用于不可压缩材料，所以在重新分解应变梯度张量的基础上，本文把MSG和SG理论拓展到可压缩材料。

It is proved that frame indifference of strain energy founctions Wof a hyperelastic materical implies symmetry of Cauchy stress tensor T,and that frame indifference of T implies symmetry of T.

证明了应变能函数的客观性意味着 Cauchy 应力张量的对称性，以及 Cauchy 应力张量的客观性将包含应变能函数的客观性，从而也导致 Cauchy 应力张量的对称性。

With the help of tensor analysis theory, the velocity field and the strain rate field during the tri-walled tube forming process are deduced, and the energy rate and the needed driving force are determined.

运用数学物理方法，遵循能量守恒定律对卷焊管电阻直热式钎焊过程进行了稳态分析，求得了焊接区上的温度分布及钎焊各工艺参数间的关系，并进一步探讨了钎焊温度波动控制策略及方法。

In the nonlinear theory the deformation tensor can be expressed as the product of two tensors, one corresponding to a rotation and the other to strain, applied sequentially.

非线性理论中，形变张量表示为与旋转相对应的张量及与应变相对应的张量的乘积。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。