基于非线性分析的高速磁浮牵引拉杆结构稳定性研究

Structural stability study of draw-bar for high-speed maglev trains based on the nonlinear analysis method

为适应高速磁浮列车在600 km/h速度下高速运行,需要优化牵引拉杆结构,提升牵引拉杆在力传递过程中的可靠性和稳定性。以600 km/h高速磁浮列车牵引拉杆为研究对象,根据稳定性分析原理,采用欧拉公式法、特征值屈曲分析方法,结合有限元法的结构稳定性原理,考虑材料非线性因素和加工误差的影响,以临界失稳载荷为指标,研究牵引拉杆轻量化材料、加工误差等因素对600 km/h高速磁浮列车拉杆结构稳定性的影响,并以此说明拉杆轻量化设计对结构稳定性的影响。通过仿真分析得出相关结论:材料力学性能对牵引拉杆临界失稳载荷影响显著,传统42CrMo合金钢拉杆的临界失稳载荷是轻质6082铝合金拉杆的3倍;加工误差影响结构稳定性,当6082铝合金拉杆存在3 mm轴向偏心误差时,临界失稳载荷由40.46 kN下降到35.45 kN,降低了12.4%,建议在设计阶段严格控制加工精度;在考虑加工误差时,非线性屈曲分析方法更适合轻量化拉杆结构稳定性分析。

It is imperative to optimize the structure and improve the reliability and stability in the force transmission process of draw-bar for the application on the high speed maglev trains in the 600 km/h operation.Taking the draw-bar used on the 600 km/h highspeed maglev trains as the research object,this paper explored the impacts of lightweight materials and machining errors on their structural stability with the critical bucking load as the index,according to the stability analysis principle,using the Euler’s formula,the eigenvalue buckling analysis method and the finite element method,and in consideration of the material nonlinear factors and machining errors,and accordingly reveals the influence of the lightweight design of the draw-bar on their structural stability.The relevant conclusions were drawn from the simulative analysis as the following.The mechanical properties of materials have a significant effect on the critical bucking load of the draw-bar,and the critical bucking load of the traditional draw-bar made of 42CrMo alloy steel is triple that of the draw-bar made of 6082 aluminum alloy.Machining errors also affect the structural stability,and the critical bucking load decreases from 40.46 kN to 35.45 kN(down 12.4%)for the draw-bar made of 6082 aluminum alloy subject to a machining error of 3 mm.Therefore,the machining precision should be strictly controlled in the design stage;the non-linear buckling analysis method is more suitable for structural stability analysis of the lightweight draw-bar.