增强机织物拉伸过程中的应力集中有限元分析

Finite element analysis of stress concentration in tensile process of reinforced woven fabric

机织物增强层是可扁平输送软管的承压骨架材料,机织物拉伸过程中,纱线力学效率会由于经纬纱在交叉点出现应力集中而降低,从而导致可扁平输送软管承压强度下降。因此,本文首先使用有限元拉伸模拟和拉伸试验研究环编斜纹织物的拉伸性能,然后针对机织物拉伸过程中交叉点处的应力集中问题,通过有限元仿真模拟不同经纱间距和不同纬纱细度斜纹织物的拉伸过程,计算交叉点处纱线横截面的应力分布和应力集中因数。结果表明:有限元拉伸模拟的结果与拉伸试验基本相符;增加经纱间距、减小纬纱细度和纬纱卷曲率可以降低纬向拉伸过程中交叉点处的应力集中程度,而经纱间距、纬纱细度、纬纱卷曲率对经向拉伸过程中交叉点处的应力集中程度没有明显影响。

Woven fabric reinforcing layer is the pressure bearing framework material of lay-flat hose.During the stretching process of woven fabric,the mechanical efficiency of yarn will be reduced due to the stress concentration of warp and weft yarn at the intersection,resulting in the decrease of pressure bearing strength of lay-flat hose.Therefore,in this paper,firstly,the tensile properties of ring knitted twill fabric are studied by finite element tensile simulation and tensile test.Then,aiming at the problem of stress concentration at the intersection in the tensile process of woven fabric,the tensile process of twill fabric with different warp spacing and weft fineness is simulated by finite element simulation,and the stress distribution and stress concentration factor of yarn cross section at the intersection are calculated.The results show that the results of finite element tensile simulation are basically consistent with those of tensile test.Increasing the warp spacing,reducing the weft fineness and weft curl curvature can reduce the stress concentration at the intersection in the process of weft stretching,while the warp spacing,weft fineness and weft curl have no significant effect on the stress concentration at the intersection in the process of weft stretching.