排序方式: 共有18条查询结果,搜索用时 15 毫秒
1.
2.
Two-wavelength method for full-field automated photoelasticity 总被引:4,自引:0,他引:4
A new method for the whole-field determination of the isoclinic angle α and the isochromatic parameter ϕ is presented. The
problems appearing during the calculation of these two parameters are solved with the use of two different wavelengths. Indeed,
when a monochromatic light is used as an incident light, α is not measurable at the points where ϕ is equal to 2kπ. In this method, each monochromatic light can compensate for the influence of ϕ to obtain the isoclinic angle for the entire
model. Also, most of the methods calculate the fractional fringe order that is unwrapped afterward to obtain the isochromatic
parameter. This unwrapping process needs an initialization, which cannot be automatic with only one isochromatic fringe pattern.
The use of two wavelengths permits a complete automatic unwrapping of the isochromatic parameter, even for the initialization
of the process. 相似文献
3.
4.
安里千 《应用数学和力学(英文版)》1991,12(6):601-604
A new method of fringe multiplication is presented in this paper.The method is simpleand applicable.Only one polarizer and one quarter-wave plate are adopted to get fringemultiplication by reflection. 相似文献
5.
聂国华 《应用数学和力学(英文版)》1994,15(6):525-535
NON-LINEARVIBRATIONOFRECTANGULARRETICULATEDSHALLOWSHELLSTRUCTURESNieGuo-hua(聂国华)(DepartmentofEngineeringMechanics,TongjiUnive... 相似文献
6.
7.
T. Y. Chen 《Experimental Mechanics》2000,40(3):256-260
A new and simple approach to the digital determination of a photoelastic fringe order using two different loads is proposed. The relationships between the intensity values of light and the isochromatic fringe orders generated from two different loads are derived. The scheme used for the automated determination of the total fringe orders of a full-field photoelastic fringe pattern is described. The usefulness of this method is demonstrated using two isochromatic fringe patterns under two different loads. Extra filters are not needed in the proposed method as in the case of the two-wavelength method. 相似文献
8.
9.
对于三维光弹模型,次主应力及其方向沿入射光连续变化,根据光学等效的原理,可以将三维光弹模型等效为一个包含线性相位延迟器和旋光器的光学模型。在集成光弹法中,对于每一个测量点,研究者必需通过实验获取三个特征参数。提出了一种用于确定集成光弹中全场特征相位差的五步相移法,给出了偏振光场中元器件的设置方法,并运用Jones算子推导出相移法得出的光强公式。最后使用斜射法对径向受压圆盘进行实验,验证了方法的有效性。 相似文献
10.
以裂尖弹性应力场的多参数模型为基础,研究I型、II型以及I/II混合型裂纹参数对光弹性条纹的影响. T应力的存在和符号影响着等色线条纹环的半径大小和旋转方向,对于纯I型或II型裂纹而言,条纹环的旋转角度只与T应力有关;而对于I/II混合型裂纹,条纹环旋转角度与K_{\rm I}, K_{\rm II}和T应力有关. T应力的存在使得I型裂纹在裂尖±π/3方向上出现2个各向同性点(T应力为正时),使得II型裂纹在裂尖后的裂纹面上出现1个各向同性点. 对于I/II混合型裂纹而言,当T应力为正时等倾线出现距裂尖半径不等的3个各向同性点;反之, T应力为负时在裂尖后只存在1个各向同性点,这些各向同性点分别与I型和II型裂纹情况具有相同的规律. 相似文献