共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
3.
4.
5.
6.
过该命题的提出和解答, 展示了定性结构力学的基本概念和运用手法, 有助于学生了解和掌
握定性结构力学的基本原理和方法. 相似文献
7.
8.
连续梁的多结点力矩分配法 总被引:1,自引:1,他引:1
计算了连续梁在结点力偶荷载作用下柔度矩阵的表达式,在此基础上,提出了
多结点力矩分配法. 对于一个承受任意荷载的$N$个结点的连续梁,该方法同时松开多个
结点,通过迭代获得各结点转角值,然后利用杆件的转角位移方程就可获得杆端弯矩的值.
该方法综合了位移法和力矩分配法的优点,较传统力矩分配法可显著减少计算工作量. 相似文献
9.
10.
讨论一般力矩分配法的适用条件. 当研究多种单元和复杂单元,提供必要的分配系
数和传递系数后,结点无侧移条件可适当放宽,成为广义的力矩分配法,但已不是工程
师所需的手算方法. 相似文献
11.
12.
针对移动粒子半隐式法MPS(Moving Particle Semi-implicit Method)基于粒子数密度来判断自由表面会出现将内部粒子误判为自由表面粒子的问题,提出了一种结合几何法和体积法的自由表面粒子判定方法。通过对溃坝问题进行数值模拟,结果表明,全新的自由表面粒子判定方法对流体平稳运动以及剧烈运动两种工况,都能准确地判断出自由表面粒子,解决了基于粒子数密度判断方法因粒子分布稀疏产生误判的问题。[JP2]这种全新的自由表面粒子判定方法对今后采用MPS方法计算两相流问题时,两种介质在界面处的传热传质计算有重要意义。 相似文献
13.
14.
15.
Nano-moire method 总被引:2,自引:0,他引:2
Nano-moiré method presented in this paper is an experimental technique which allows direct measurement of nanoscopic mechanical
parameters, such as displacement, strain and dislocation distribution. The basic idea is the formation of moiré fringes when
a HREM (high resolution electron microscopy) image of crystal material is superimposed with a unidirectional grating. Fourier
filtering technique is used to increase the contrast of fringes and to multiple the fringes. This method has atom-size sensitivity
and spatial resolution, and relatively large range. It provides a new experimental technique with very high sensitivity and
spatial resolution for nanomechanics.
The project supported by the National Natural Science Foundation of China 相似文献
16.
17.
根据投影浸入边界法分步投影求解的特点,同时针对压力泊松方程离散后的大型稀疏线性方程组是非奇异非对称的特点,结合开源函数库UMFPACK,在传递线性方程组的系数矩阵和右端向量时,采用函数库Eigen将系数矩阵的数据结构改写优化,大大降低了存储空间,实现对高维大型稀疏线性方程组的快速求解,同时求解保持良好的稳定性。本文首先利用一具有解析解的数值算例验证了求解泊松方程数值方法的准确性和网格依赖性,进而利用VC++编写投影浸入边界法的数值计算程序,以单圆柱绕流为基准数值算例,通过与其他文献和实验结果的对比,验证了投影浸入边界法数值计算结果的可靠性,并进一步分析了不同雷诺数下圆柱绕流的流场结构特征和尾涡结构的动态演化过程。 相似文献
18.
19.
Formerly, the authors presented one-dimensional strain analysis by a moiré method using a Fourier transform. In the present work, the method is extended to two-dimensional strain analysis. The analysis is completely automated by introducing digital image processing. All of the laborious and subjective procedures required in the classical and conventional moiré method, such as separation of the two gratings, fringe-sign determination, fringe ordering and fringe interpolation, are completely eliminated; and objective, fast and accurate analysis can be made.currently Engineer, Kansai Electric Power Co. Inc.Paper was presented at the 1988 SEM Spring Conference on Experimental Mechanics held on June 5–10 in Portland, OR. 相似文献
20.
A. J. Q. Alkemade F. T. M. Nieuwstadt E. van Groesen 《Flow, Turbulence and Combustion》1993,51(1-2):3-7
After a general introduction to the vorton method, which is a vortex method resembling the 2-D point-vortex method, a set of equations describing dynamics of 3-D vortex singularities (vortons) is derived, avoiding the inconsistency in the derivation of other vorton equations which have been applied. Though inviscid, numerical simulations show reconnection phenomena. 相似文献