制动胶管纤维编织层的三维模型构建及其等效力学性能研究

Construction of 3-Dimensional Model and Prediction of Effective Mechanical Properties of the Reinforced Fibrous Braid Layer of Brake Hose

以汽车用制动胶管的纤维编织骨架层为研究对象,在有限元分析的前处理模块中构建纤维编织层三维几何模型,详细介绍了模型截面尺寸的确定、经纬线间和单丝纤维间相互作用的建立、协同性边界条件的施加以及规整网格的划分。将纤维编织层当作正交各向异性材料处理,通过有限元分析方法求解其等效力学性能,利用叠加原理求解其等效杨氏模量和泊松比,利用有限元分析编织层简单剪切变形,求得编织层等效剪切模量。同时探索编织层经纬线间摩擦系数对其应力的影响。结果表明,编织层的径向杨氏模量最大,周向杨氏模量次之,轴向杨氏模量最小;对于剪切模量而言,径向最大,周向和轴向在数值上相近;摩擦系数对剪切应力τxz影响较正应力δx和剪切应力τxy大。

Take the fabric braided layer of brake hose as an example,the method and process of constructing 3-dimensional model of the braided layer were introduced,mainly including the determination of cross section of fiber model,the creation of interaction in fibers/fibers and wraps/fills,the application of synergistic boundary conditions and the creation of regular mesh.The braided layer was treated as an orthotropic material,and its effective mechanical properties were predicted by finite element method（FEM）-Young’s modulus and Poisson’s ratio were determined by the superposition principle,shear modulus was also calculated.Meanwhile,the influence of friction coefficient between wraps and fills on the stress of braided layer was explored.The results showed that the Young’s modulus in the radial direction was highest compared with those in the circumferential direction and axial direction,and the Young’s modulus in the axial direction was lowest.Shear modulus in radial direction was also the highest,while the shear moduli in the other two directions were approximately equal;and the influence of friction coefficient on shear stressτxzwas greater than normal stressδxand shear stressτxy.