【作者】 王雷；

【导师】 刘堂红； 沙淼；

【作者基本信息】 中南大学 ， 交通运输（专业学位）， 2024， 博士

【摘要】 我国现有高速铁路最高设计速度为350 km/h,为满足繁忙干线大运能需求,我国正在加紧研发400 km/h高速列车。运行速度从350 km/h提升到400 km/h,列车各项气动性能激化,如明线运行气动阻力增加近30%,隧道内交变压力激化危及车体结构安全与人体舒适性变差等。因此,为满足既有350 km/h高速铁路线路运行400km/h高速列车,亟待开展列车400 km/h运行气动性能边界,即气动载荷阈值与标准研究,并开展参数匹配设计以满足节能、安全、舒适运行要求。本文采用数值计算、风洞试验与动模型试验相结合的方法,开展了以下主要工作:(1)建立了既有铁路边界约束条件下更高速度列车气动性能数值仿真模型,剖析了列车以400 km/h高速运行时气动阻力、倾覆力矩以及车隧交变压力等气动载荷变化规律,确定了不同运行场景下列车从350 km/h提速到400 km/h运行时的气动阈值。研究结果表明:高速列车以400 km/h运行时明线气动阻力比350 km/h增加31%;高速列车在最不利隧道长度内交会时,负压极值超车体承载指标约4.7 k Pa,超幅达78.2%;大风环境下,最高运行速度对应的临界倾覆风速由15 m/s降至12 m/s。(2)构建了400 km/h高速列车头尾协同车体界面平顺化的综合气动减阻设计方法,提出了高速列车头部整体构型-局部调控的头型优化设计模型,揭示了气动外形全局参数影响下的转向架、受电弓等关键区域流动抑控作用机理。研究结果表明:仅头尾车流线型头部及断面优化,实现八车编组列车气动减阻6.51%;提出的转向架裙板与头尾车底板包覆耦合方案,实现气动减阻11.91%;提出的新型受电弓设计方案可减阻3.74%;综合头型优化、转向架包覆以及受电弓优化方案,最终实现八车编组列车气动减阻21.56%。(3)开展了400 km/h高速列车通过隧道气动性能及参数匹配研究,确定了外形优化列车与原型车单车过隧道和隧道内交会时的气动特性差异,提出了基于既有线路参数下的外形优化列车气密性和车体结构疲劳强度载荷阈值。研究结果表明:单车过隧道时,外形优化列车相较于原型车车体壁面压力峰峰值降低9.04%,距隧道出口20 m和50 m处微气压波幅值分别减小10.96%和10.88%;确定了列车通过最不利隧道和交会时的车体临界动态气密指数为τ=44.34s;提出了循环次数为100万次和1000万次对应的车体结构疲劳载荷阈值分别为±4.6 k Pa和±2.1 k Pa。(4)建立了400 km/h高速列车动力学参数与线路边界匹配设计方法,提出了列车转向架悬挂参数优化方案,构建了风环境下400km/h高速列车安全运行风速-车速阈值。研究结果表明:当列车速度为400 km/h时,优化后临界倾覆风速达到15 m/s,与既有高速列车对应的12 m/s相比提高25%。本研究成果可为既有350 km/h等级高速铁路开行400 km/h高速列车提供支撑。图141幅,表56个,参考文献142篇更多还原

【Abstract】 In order to meet the soaring demand for high-capacity transportation on busy railway mainlines,it is imperative to further increase the operating speed of high-speed trains in China from 350 km/h to 400 km/h.However,such an increase in speed will lead to intensified aerodynamic effects on various aspects of the train,such as an approximately 30%increase in aerodynamic drag during the train’s open-air operations and an exacerbated pressure change inside tunnels posing risks to the structural safety of the train and passenger comfort.Therefore,in order to operate 400 km/h high-speed trains on existing 350 km/h high-speed railway lines,it is urgent to research the aerodynamic performance boundaries of the trains running at 400 km/h,that is,clarify the aerodynamic load thresholds and relevant standards,and conduct parameter-matching design to meet the requirements of energy saving,safety and comfortable operation.This thesis adopted numerical simulations,wind tunnel tests,and moving model experiments to carry out the following main tasks.(1)A numerical simulation model of the aerodynamic performance of higher-speed trains was established under the constraints of existing railways,sensitive areas of aerodynamic loads such as aerodynamic drag,overturning moment,and tunnel-train interaction pressure were analyzed when the train operates at 400 km/h,and the aerodynamic thresholds for high-speed trains accelerating from 350 km/h to 400 km/h were determined under different operating scenarios.The research results show that:when the high-speed train operates at 400 km/h in the open air,the aerodynamic drag exceeds the requirement by 31%;when the high-speed train passes through the most adverse tunnel length,the maximum negative pressure exceeds the train body’s bearing standard by 78.2%with approximately 4.7 k Pa;in strong-wind environments,the critical overturning wind speed decreases from 15 m/s to 12 m/s.(2)A comprehensive aerodynamic drag reduction method was developed for the coordinated smoothing of the head and tail interfaces of400 km/h high-speed trains.The study proposed an optimization design model for the overall configuration and local adjustment of the train’s head and analyzed the flow control mechanism of key areas such as the bogie and pantograph under the influence of global aerodynamic shape parameters.The research results show that:optimizing the streamlined shape of the train head and tail can achieve an aerodynamic drag reduction of 6.51%for an eight-car train;the proposed scheme of coupling the fairings of the bogies with the bottom plates of the head and tail cars can achieve an 11.91%aerodynamic drag reduction;the proposed new pantograph design scheme can reduce drag by 3.74%;combining head shape optimization,bogie covering,and pantograph optimization can achieve a 21.56%aerodynamic drag reduction for an eight-car train.(3)A study was conducted on the aerodynamic thresholds of 400km/h high-speed trains passing through tunnels and the parameter matching design to existing railway lines.The research analyzed the differences in aerodynamic characteristics between the shape-optimized and prototype trains in two typical scenarios,namely a single train passes through a tunnel and two trains intersect in a tunnel,and determined the airtightness and structural fatigue load thresholds for the shape-optimized trains based on existing railway line parameters.The research results show that:compared to the prototype train,the peak-to-peak pressure on the surface of the optimized train is reduced by 9.04%when a train passes through the tunnel,and the micro-pressure wave amplitude at distances of20 m and 50 m from the tunnel exit is reduced by 10.96%and 10.88%,respectively.The critical airtightness index for the train passing through the most adverse tunnel in the intersection scenario is determined to beτ=44.34 s;a fatigue load threshold of±4.6 k Pa corresponding to a circulation of 1 million times is proposed.(4)A method for matching the dynamic parameters of 400 km/h high-speed trains with the limitations of railway lines was established.The study proposed an optimization scheme for the suspension parameters of the train’s bogies and constructed a speed limitation for the safe operation of400 km/h high-speed trains in wind environments.The research results show that:the crtical overturning wind speed for the optimized trains increases to 15 m/s under the operation speed of 400 km/h,which is 25%higher than the current standard of 12 m/s corresponding to the existing trains at the same operation speed.The research findings support the operation of 400 km/h high-speed trains on existing 350 km/h high-speed railway lines.更多还原