轴向拉紧的圆弧端齿轴段扭转特性研究

Torsional Characteristics of Axial Fastened Shaft Section with Curvic Couplings

为了研究轴向拉紧的圆弧端齿轴段的扭转特性,提出了圆弧端齿轴段传扭特性的分段线性模型,给出了分段线性转折点处扭矩的估计值,同时建立了轴向预紧圆弧端齿轴段三维有限元模型,采用数值计算对理论分析进行了验证。此外,通过数值计算求得圆弧端齿轴段的双线性扭转刚度,并进一步研究了预应力、摩擦系数等参数对圆弧端齿扭转特性的影响。研究结果表明:圆弧端齿结构具有典型的软弹簧双线性扭转特性,预应力对圆弧端齿的传扭特性有影响且存在预紧饱和现象;预紧饱和后,圆弧端齿双线性刚度基本不受预应力的影响,分段线性转折点扭矩则与预应力成正比;摩擦系数对圆弧端齿双线性刚度的起始段刚度基本无影响,仅对线性特性的第二段刚度有影响,扭转刚度随摩擦系数的增大而增大。研究结果对工程应用中端齿连接的设计及重型燃气轮机转子动力学分析具有参考价值。

To reveal the torsional characteristics of axial fastened shaft with curvic couplings,a piecewise linear torsional deformation model for the shaft section with curvic couplings is proposed,and the torque at the turning point is estimated.Additionally,a 3-D finite element model for the axial pre-tightened shaft section with curvic couplings is created to validate the theoretical analysis.The bilinear torsional stiffness is obtained by numerical analysis,and the effects of prestress and friction coefficient on torsional behaviors are discussed.The results show that the shaft section with curvic couplings has typical bilinear torsional characteristic of soft spring,the prestress affects torsional behaviors,and there exists a preload saturation.In the saturated preload state,the bilinear torsional stiffness has almost no relation with prestress,and the torque at the turning point gets proportional to the prestress. Moreover,the friction coefficient exerts almost no effect on the primary bilinear torsional stiffness,but heightens the secondary one.