内轴颈高铁车轴结构设计与强度分析方法

针对高速列车的轻量化设计需求，分析了内轴颈高铁车轴独特的内支承结构与承载特点，建立了内轴颈高铁车轴受力状态和结构强度理论分析模型，提出了内轴颈高铁车轴设计极限载荷和疲劳强度的解析计算方法；在此基础上，制定了基于理论分析、有限元方法和车辆系统动力学的内轴颈高铁车轴结构设计方法，并以17 t轴重的内轴颈高铁车轴为例开展了应用研究；基于内轴颈高铁车轴受力状态的理论分析结果，确定了车轴的临界安全截面和详细尺寸方案；建立了内轴颈高铁车轴的有限元模型，评估并校核了车轴的疲劳强度；建立了轴箱内置式高速动车的刚-柔耦合系统动力学仿真分析模型，验证了车辆的动力学性能和车轴的动荷载。分析结果表明：17 t轴重的新型内轴颈高铁车轴的质量为273.6 kg，比同轴重传统外轴颈高铁车轴的质量低约30%；内轴颈高铁车轴各截面疲劳强度的安全系数均大于1.66，临界安全截面转移至轴颈与轮座之间的卸荷槽及轴颈与轴身之间的过渡圆弧区域；采用内轴颈车轴的高速动车能够以350 km·h^-1的速度稳定通过半径为5.5 km的曲线线路，主要动力学性能指标优良；在选定曲线通过工况下车轴所承受的动载荷均能被设计极限载荷包络，据此开展的车轴结构设计和强度分析是稳健的。可见，内轴颈高铁车轴在实现高速列车轻量化设计方面有显著的技术优势，且高速适应性较好，在高速列车领域的发展和应用潜力巨大。

Structural design and strength analysis method for inner journal high-speed railway axles

To achieve the lightweight design of high-speed trains, the unique inner supporting structures and load-bearing characteristics of inner journal high-speed railway axles were analyzed, and a theoretical model to study both the load-bearing status and structural strength was established for the inner journal high-speed railway axle. An analytical calculation method was proposed to calculate the design limit load and fatigue strength for the inner journal high-speed railway axle. Based on the presented methods, theoretical analysis, finite element method, and vehicle system dynamics, a structural design method was developed for inner journal high-speed railway axles. Further, an inner journal high-speed railway axle with a 17-t axle load was used as a case study to carry out the application research. The critical safety section and detailed dimension scheme of the axle were determined using the theoretical load-bearing analysis results of the inner journal high-speed railway axle. A finite element model for the inner journal high-speed railway axle was established, and the fatigue strength of the axle was evaluated and verified. A rigid-flexible coupled system dynamics simulation analysis model for the high-speed electric multiple unit (EMU) with inner journal axles was constructed. The dynamics properties of the vehicle and the dynamic loads of the axle were obtained and verified. Analysis results reveal that the weight of newly developed inner journal high-speed railway axle with a 17-t axle load is 273.6 kg, about 30% less than that of the traditional outer journal high-speed railway axle. The safety factor of fatigue strength for each section of inner journal high-speed railway axle is larger than 1.66. The critical safety sections are transferred to the bottom of relief groove between the journal and the wheel seat as well as to the arc-shaped transition zone between the journal and the axle body. The high-speed EMU with inner journal axles can stably pass through a curved route with a radius of 5.5 km at a speed of 350 km·h-1, and its main dynamics property indices are excellent. The dynamic loads borne by the axles under the selected curve passing conditions fall within the design limit loads. Therefore, it is robust enough to carry out the structural design and strength analysis for the axles. Thus, the inner journal high-speed railway axle shows significant technical advantages in achieving the lightweight design of high-speed trains with excellent high-speed adaptability. It has immense development and application potential in the field of high-speed trains. 2 tabs, 10 figs, 32 refs.