基于W305液力变矩器的系列化设计

以W305液力变矩器为基型,通过试验研究和统计资料,确定了液力变矩器的系列化型谱;利用CFD数值分析软件对W305变矩器内部流场进行分析计算,基于计算结果进行W305液力变矩器的系列化设计;对于有效直径不同的液力变矩器,介绍了与基型变矩器相似设计的方法。     

液力变矩器计算机辅助设计与制造

本文简述了液力变矩器设计与制造的研究和发展，以及计算机在液力变矩器设计与制造行业的应用，指出了存在的问题；建立了液力变矩器计算机辅助设计与制造的一体化系统；实现了液力变矩器性能预估、叶形判断与叶栅系统入，出口参数计算的有机统一。     

CAD／CAM一体化技术在液力变矩器研制中的应用

液力变矩器是一种以液体为介质的叶片机械，它能将发动机的机械能平稳地传到车轮，使车辆实现无级传动。介绍了如何在液力变矩器的研制中运用ＣＡＤ／ＣＡＭ一体化技术。由于新技术的采用，保证了液力变矩器的制造精度。     

浅析自动变速器液力变矩器的故障诊断

本文介绍了液力变矩器的基本检查,提出了一些检修液力变矩器的方法,重点分析了导致液力变矩器故障的原因以及故障诊断思路。     

乘用车液力变矩器优化设计研究综述

综述了液力变矩器优化设计过程中各个阶段的研究进展和现状。从液力变矩器设计与参数化方法、设计参数对性能影响、性能预测模型和优化设计方法这4个方面的研究进行论述,并对液力变矩器应用新技术进行了概述。总结每个阶段的研究成果,最后展望了下一步的研究方向。     

液力变矩器叶片设计和特性计算的通用程序及其应用

给出了液力变矩器叶片设计和特性计算的通用程序,提出了在计算机上实现加厚叶片设计和数学模型建立的方法.所给通用程序不仅具有计算和绘图能力,而且可进行多方案比较.介绍了利用该程序对DFZFB-323型变矩器进行的多方案叶片设计和特性计算,并与试验结果作了对比.     

发动机与液力变矩器的匹配分析

本文首先介绍了机械动力传动系统及其匹配方法,然后介绍了动力系统匹配流程,最后以一款机械设备为例,通过发动机与液力变矩器的优化,详细的说明了发动机与液力变矩器的应用匹配情况。     

轿车液力变矩器的改进设计方法研究

由于工作介质流动状况复杂，难以形成准确、可靠的轿车液力变矩器设计方法，本文建立了液力变矩器内流场的计算模型，得到了正确，可信的轿车液力变矩器内流场计算结果，在分析后，本文认为泵轮流道入口处的径向扩张影响了液力变矩器的性能，依此，本文成功地改进了该液力变矩器。     

基于CFD的泵轮叶栅关键参数对液力变矩器的性能影响预测

基于计算流体力学理论,利用Pro/E建立某型液力变矩器叶栅系统全流道模型。借助多重参考系技术,采用FLUENT软件对液力变矩器内流场进行数值模拟,并与原结构的试验结果对比,验证了该模型的合理性。在此基础上,研究了泵轮叶片进口角和出口角等关键参数对液力变矩器性能的影响。结果表明,增大叶片进口角或减小叶片出口角,可降低失速变矩比、K因子和改善高速比下液力变矩器的传动效率。     

具有双离合器的液力变矩器的结构设计

将液力变矩器与机械式自动变速器合理匹配可组成一种新型自动变速系统，其性能接近自动变速器，但成本降低。为该系统设计了具有双离合器(闭锁离合器，换档离合器)的液力变矩器。阐述了该液力变矩器的结构、工作原理及特点。试验结果表明，所设计液力变矩器可支持新型自动变速系统成为现实。     

Hydraulic retarders for heavy vehicles: Analysis of fluid mechanics and computational fluid dynamics on braking torque and temperature rise

Hydraulic retarders are auxiliary braking devices that reduce the velocity of a vehicle, particularly when a vehicle is driven downhill. Such velocity reduction could reduce the potential risk caused by brake failure caused by the service brake working for a long time and the temperature of the brake shoe becomes extremely high. This paper introduces the construction of the hydraulic retarder and proposes two mathematical models for the hydraulic retarder. The first mathematical model is deduced by using fluid mechanics, which is used to analyze the mechanism of how braking torque is produced and the key factors that can influence the value of the braking torque. The second mathematical model is deduced by using thermodynamics, which is used to quantify the heat produced by the hydraulic retarder. This research emphasizes that the flow rate and the average velocity of the working fluid in the working chamber mainly determine the braking torque of the hydraulic retarder. The flow rate into and out of the working chamber determines the temperature rise of the working fluid. Computational fluid dynamics (CFD) simulations are conducted with the Reynolds-averaged Navier-Stokes (RANS) and Shear Stress Transport (SST) turbulent models. Experiments are carried out to justify the two mathematical models and the CFD simulations. The results show that the mathematical models are capable of describing the force analysis and energy conversion of the hydraulic retarder and SST is more accurate for CFD simulation and the error is within 6 %.     

基于CFD的液压阻尼器低速特性仿真分析

以液压阻尼器结构特点为基础,采用预留液体间隙层方法模拟阻尼器的内部泄漏,建立了具有较高精度的阻尼器流体网格模型,应用计算流体动力学(CFD)数值方法对其进行了仿真分析,获得了阻尼器低速特性以及内流场规律.测试结果验证了CFD仿真分析的准确性.     

Hydraulic control system design for a PHEV considering motor thermal management

In this paper, a design method for a PHEV hydraulic control system was proposed considering motor thermal management. Dynamic models of the target PHEV were developed including the hydraulic system, which consists of one mechanical and one electric oil pump. The required motor cooling flow was designed based on the motor temperature, which was obtained from a one-dimensional thermal equivalent circuit model including the heat source and oil spray cooling. Combining the PHEV powertrain model, hydraulic control system model, and the motor thermal model including the cooling system, an integrated simulator was developed for the target PHEV. Using the integrated simulator, the temperatures of MG1 and MG2 were investigated for various motor cooling flow rates when the PHEV underwent a highway driving cycle. The energy consumption of the hydraulic control system was also evaluated. It was found from the simulation results that a hydraulic control system of the target PHEV could be designed that satisfied the required flow for the motor cooling, lubrication and brake control using the design procedure proposed in this study.     

电喷汽油机进气歧管的CAD/CFD设计

电喷汽油机的进气系统对整个发动机的动力性、经济性和排放特性有很大的影响，其中进气歧管的尺寸和结构形状是主要的影响因素，需要进行优化设计。文中用CAD／CFD对EQ49li电喷汽油机的进气歧管进行优化设计，并用试验对计算机模型进行验证，整个设计过程表明，所用CAD／CFD优化方法是一种有效的和切实可行的发动机进气系统设计方法。     

基于混杂理论的电磁与摩擦集成制动方法

鉴于传统电子液压制动系统连续制动易产生"热衰退"现象，结构缺陷导致的制动响应慢，制动系统与电控系统衔接差等缺点，提出了一种基于混杂自动机模型的电磁与摩擦集成制动方法。首先分析集成制动器制动时的工作特点以及不同情况下对应的工作模式（纯电磁制动、纯摩擦制动以及集成制动），并确定3种制动模式的切换条件，通过逻辑门限算法将其实现。根据制动时车辆既具有连续运动状态又有离散状态的混杂特性，使用MATLAB/Stateflow建立基于制动模式切换系统的推广自动机模型，并根据制动模式切换控制策略，对3种制动模式切换进行试验，验证制动模式切换控制策略的合理性。最后选取车辆制动初速度为28 m·s^-1的直线制动工况，分别在高附着系数（0.85）以及低附着系数（0.3）的路面条件下，通过试验平台对控制算法和制动系统性能进行试验验证。研究结果表明：所提出的汽车混杂理论模型以及优化方法在在低附着系数（0.3）路面条件下，集成制动方法较传统液压制动系统缩短5.12%的制动距离，缩短制动时间0.3 s；在高附着系数（0.85）路面条件下，集成制动方法较传统液压制动系统缩短5.66%的制动距离，缩短制动时间0.2 s，能有效提高制动效能。     

增压器涡轮性能试验与CFD计算方法的研究

建立了蜗壳与整周叶轮合并的增压器涡轮整机计算模型,在较少的网格数量下,用CFD方法对涡轮内部的流动进行了模拟,得到了涡轮的运行特性,如流量特性、转速特性、效率等。将计算结果与相同条件下的试验结果进行比较,可以看到计算结果基本符合增压器设计阶段性能考核的要求,具有工程化应用的意义。     

Simulation of an airbag deployment in out-of-position situations

The commonly used 'uniform pressure method' (UP) is a well-tried method to simulate an airbag deployment in accident cases. Nevertheless, this method indicates rather heavy inadequacies at the examination of the airbag deployment in the first milliseconds. A solution is the airbag deployment calculation by using computational fluid dynamics (CFD) methods, wherein the calculated gas flow pressure may be applied 'correctly' to the airbag shell elements.

This CFD simulation is integrated in LS-Dyna with the so-called Arbitrary Lagrangian Eulerian (ALE) method and in this review the result's accuracy will be discussed. According to the FMVSS 208, an OoP model will be built-on and comparisons with simulations and tests are done. Another important detail in this labour is the airbag cover examination and the tear seam modelling, as a trivial FE modelling cannot be done due to the very fine mesh. So two possible solutions for tear seam modelling are introduced and discussed. Furthermore considerations concerning the gas generator combustion will also be revealed and an analysis about the impossibility of the direct comparison between gas generator tank test and airbag deployment will be done. At least some parameters, which take effects in the simulation, are researched and evaluated, so finally an optimised simulation model can be made available for further examinations.     

基于位移与轴力的软土深基坑开挖扰动控制

针对软土地层基坑工程钢支撑体系压力控制液压伺服反馈控制中施工扰动最终位移的不确定性及其环境风险,研究建立了以扰动位移控制为核心、位移与支撑轴力综合优化的钢支撑液压伺服智能控制方法。提出基于容许位移约束的线性位移变化与支撑力综合优化智能控制模式,并建立相应的施工全过程实时调压技术。构建了基于高精度激光测距和液压监测同步的反馈系统,采用形函数的随机数据误差处理方法,有效防范随机误差带来的反馈控制失误和风险。经模型试验,验证了该方法的可靠性和适用性。经上海世博通道工程示范应用,位移控制效果显著。     

比亚迪汉空气动力学开发

汉是比亚迪基于全新纯电动车平台开发的一款车型,为增加续驶里程对整车的风阻系数提出了极高的要求。全新的造型设计风格对风阻开发带来很大挑战,为实现风阻目标搭建了一套适用的空气动力学开发流程,并以 CFD仿真为主要开发工具,分别完成外造型、前舱、车底部、主动进气格栅和低风阻轮辋等附件的空气动力学开发,最后通过实车风洞试验进行验收。对该车型的风洞试验仿真对标发现,采用分离涡模拟（Detached Eddy Simulation,DES）湍流模型可以获得较高的风阻仿真精度。     

CFD的水泵数值分析

CFD模拟可以直观了解产品内的复杂流动现象,对提高设计能力、改进和优化设备具有重要的作用。文章建立了发动机冷却水泵的实际工作模型,对水泵体内部的三维湍流流场进行CFD模拟;研究了水泵内部复杂流场中各个位置上压力分布、速度分布和湍动能情况;分析水泵的水力损失,对发动机水泵的扬程和水力效率性能进行分析和预测,计算结果与试验结果相差不超过8％,表明利用CFD数值模拟分析具有很高的可靠性,能充分反映水泵内部流动的复杂情况,可以为水泵结构设计和性能改进提供理论依据。