锥形缸体球面配流副润滑特性建模及试验验证

配流副油膜的润滑特性对轴向柱塞泵的可靠运行有重要影响。建立了锥形缸体球面配流副油膜润滑特性仿真模型,并通过试验验证了模型的有效性。对锥形缸体进行受力分析,通过对柱塞滑靴组件运动学和受力的分析,求解得到柱塞滑靴组件对锥形缸体的作用力;通过对球面配流副油膜厚度分布和压力分布的分析,求解得到球面配流副对锥形缸体的油膜支承力;采用有限容积法对油膜进行离散化处理,通过牛顿迭代法数值求解球面配流副油膜润滑特性和锥形缸体运动方程;开展轴向柱塞泵高压稳态试验和轮廓扫描试验,获得不同稳态试验时长的球面配流盘磨损形貌,对比球面配流盘磨损轮廓与仿真得到的油膜厚度分布和压力分布。研究结果表明,仿真得到的油膜厚度较小区域与配流盘主要磨损区域相近,验证了锥形缸体球面配流副油膜润滑模型的有效性。     

油膜破裂条件下柱塞泵配流副摩擦磨损性能研究

为了探究轴向柱塞泵配流副工作过程中油膜破裂时,配流副接触情况和磨损。根据配流副在实际工况建立了配流盘与缸体摩擦副的流-热-力耦合模型和基于退化系数的磨损预测模型。分析边界润滑条件（油膜破裂）下配流副温升、应力、应变及磨损。并分析了温升对应力、应变和磨损的影响。研究结果表明：配流副接触面应力、应变随油液压力呈周期性变化。油膜破裂情况下,缸体旋转360°最大温升为30.560℃。配流盘的最大应力为90.046MPa,相较于不考虑温升应力增大了21.310MPa。且配流盘应力分层,使得配流盘变形分化,变形主要发生在配流盘排油区外密封带。通过磨损模型分析,油膜破裂下缸体旋转360°磨损量为0.0033mg,相较于不考虑温升磨损增加了0.0009mg,说明温度会加剧磨损。     

基于摩擦配副变形的轴向柱塞泵配流副流固热耦合影响因素分析

通过考虑轴向柱塞泵配流盘摩擦配副的缸体和配流盘耦合变形,建立了配流副的热流固多场耦合仿真分析模型。用有限元法求解模型中的柱塞流道压力场和温度场以及配副耦合热变形,其结果能够可视化地实时观测在整泵运动过程中两配副表面不同的温度和变形动态分布过程,从而揭示出多因素对其表面油液润滑特性的影响规律,并指出各因素的影响的权重。结果表明：配流副油液的压力和温度与配副两表面的热弹性变形量的具有耦合交互影响,在轴向柱塞泵的配流副高压压油区,由于压力较大,此区域结构变形和温度分布较大。不同工况条件下,压力和转速的提高,会导致结构的应力变形和温度分布成正相比。压力对变形和温度的影响权重均大于60%,明显大于速度的影响,压力对其起着决定性作用。     

轴向柱塞泵配流副间隙的实验研究

一、前言由缸体和配油盘组成的配流副是轴向柱塞泵的关键部件之一。轴向柱塞泵的故障有相当一部分是由于配流副的磨损失效引起的。为了弄清配流副油膜厚度及其变化规律,笔者实测了B_1-725型斜轴式轴向柱塞泵配流副的油膜厚度,考察了油泵压力、转速、油温及缸体摆角的变化对油膜厚度的影响。     

轴向柱塞泵平面配流副的优化设计模型研究

轴向柱塞泵平面配流副的优化设计模型研究李小宁毕诸明路建萍（南京理工大学制造工程学院２１００９４）１引言轴向柱塞泵平面配流副是指由泵缸体与配流盘组成的转动摩擦副。在工作时，配流副之间的高压液体对缸体产生必要的反推力和反推力矩，以平衡柱塞对缸体产生的压紧...     

轴向柱塞泵配流盘摩擦副材料的磨损实验研究

轴向柱塞泵结构相对紧凑复杂,其可靠性与寿命的长短主要取决于三大摩擦副,缸体-配流盘摩擦副、缸体-柱塞摩擦副和斜盘-滑靴摩擦副,同时与该三对摩擦副的热处理工艺、加工精度以及配对材料相关,其中选用合理摩擦副材料最为重要。该文开展轴向柱塞泵缸体-配流盘摩擦副的磨损实验研究,选用缸体材料为烧结铜、ZQAL9-4,选用配流盘材料为25Cr3MoAl、18CrMnTi以及38CrMoAl,组成三对摩擦副,使用立式万能摩擦磨损试验机进行实验。结果发现以烧结铜、38CrMoAl为配对材料的摩擦副摩擦系数较低,且具有最小的磨损量,可以推荐作为轴向柱塞泵配流副材料选用,实验结果为解决配流盘磨损问题提供一定的参考性依据。     

基于分形理论的柱塞泵/马达配流副润滑特性研究

为研究配流盘表面形貌对配流副润滑特性的影响,采用分形理论模拟配流盘表面形貌,建立轴向柱塞泵配流副润滑模型,使用有限差分法对模型进行求解,探讨分形参数对表面轮廓的影响,并进一步分析分形参数和配流副工况参数对油膜承载力、摩擦力、摩擦转矩和摩擦因数的影响。结果表明：分形维数越大,表面轮廓形貌复杂度越高,且粗糙表面高度随尺度系数减小而降低;随着缸体倾角和转速的增大,油膜承载力提升,但摩擦力、摩擦转矩和摩擦因数也随之升高;配流副润滑性能与分形维数呈现正相关的关系,选取较大的分形维数有利于提升配流副的润滑性能;尺度系数越小其摩擦力越小,但承载力也减小,因此需选择适中的尺度系数。     

柱塞泵倾斜缸体配流副流场特性分析

通过建立柱塞泵倾斜缸体配流副油膜控制方程,并采用有限差分法对其进行了求解。研究分析表明:配流盘一侧通高压油,一侧通低压油,缸体会发生倾斜;当缸体高速运转时,在倾斜缝隙处形成了流体动压效应,提高了油膜负载能力,降低柱塞泵发生烧盘现象的可能性;缸体转速升高,流体动压效应提高明显。     

轴向柱塞泵配流副油膜的实验研究

本文通过实测配流副间的油膜厚度,分别考察了转速,压力和斜盘摆角变化对油膜厚度的影响。根据实测数据综合分析,探讨了轴向柱塞泵配流副早期磨损“烧盘”的机理及其成因,并提出改善配流副工作性能的措施。     

考虑弹性变形的柱塞泵配流副温度特性研究

针对柱塞泵配流副的温度特性问题,建立了柱塞泵配流副的数学模型,在考虑弹性变形情况下,对柱塞泵配流副温度特性进行了研究。运用Fortran和MATLAB软件对数学模型进行了计算仿真,在油膜压力作用下,计算了配流副的弹性变形分布形态,得到了配流副的热弹流分布;对比了不同工况参数下的油膜温度最高值,分析得出了油膜的油液黏度、缸体转速、缸体倾角、初始油膜厚度、密封带宽度等单一参数对油膜温度特性的影响,并与未加入弹性变形的配流副的温度特性进行了比较;最后通过温度测试的实验,验证了该计算结果的正确性。研究结果表明:在两种不同情况下,油液黏度不同时各工况参数对温度的影响趋势保持一致;在考虑弹性变形的情况下,各工况参数对温度的影响程度不同;该结果可对后续柱塞泵配流副热流固耦合这一研究方向提供理论基础和计算依据。     

考虑表面接触力的滑靴副油膜特性分析方法

由于受倾覆力及刚体表面粗糙度影响,液压柱塞泵斜盘-滑靴运动副(滑靴副)在相对运动时处于混合润滑状态。斜盘和滑靴表面接触引起弹性和塑性变形,进而产生表面接触力。接触力与油膜厚度密切相关,在油膜特性分析时不应被忽略。提出一种基于流体动压润滑理论的滑靴副油膜特性(油膜厚度、压力分布、油膜间隙流量)的分析与计算方法,考虑了滑靴副粗糙表面的支撑力影响。在雷诺流体动压润滑方程基础上,考虑滑靴副刚体表面粗糙度水平和油膜厚度,计算液压柱塞泵不同工况下的表面接触支撑力,并将接触力融入运动副的受力方程。提出了基于改进的雷诺流体动压润滑方程的数值计算方法,并进行了仿真分析,通过间接对比滑靴副间隙流量的仿真结果,证实了提出方法的有效性和结果的准确性。     

Experimental and Analytical Investigation of Floating Valve Plate Motion in an Axial Piston Pump

The purpose of this investigation was to experimentally measure the motion of the floating valve plate in an axial piston pump under various operating conditions and to develop a model to determine how the floating valve plate motion affected the lubricating pressures between the valve plate and cylinder block. In order to achieve the objectives, a hydraulic circuit was designed and developed to incorporate and operate a floating valve plate axial piston pump. The hydraulic circuit integrating the axial piston pump (axial piston pump apparatus, APPA) consists of a series of valves, pressure sensors, a charge pump, flow meters, temperature sensors, a heat exchanger, and proximity probes. The floating valve plate axial piston pump housing was modified to incorporate three proximity probes to measure the valve plate position and motion relative to the cylinder block, thus allowing for determination of the film thickness within this contact. The results illustrate that as the pump starts up the valve plate experiences vibrations and begins to lift relative to the cylinder block. Then as the pump reaches steady-state operation the valve plate achieves a fixed position and tilt. The results also demonstrate that under steady-state operation, the valve plate vibrates and this vibration correlates well with the speed and the number of pistons in the pump. The measured film thickness results were then used in a lubrication model to determine the pressures generated between the floating valve plate and the cylinder block. The analytical results highlight how the motion of the valve plate directly correlates to the pressure pulsations seen in the lubricating gap.     

超高压斜盘式轴向柱塞泵柱塞副摩擦界面油膜固液耦合作用特性研究

作为液压传动系统核心动力元件的轴向柱塞泵,超高压化是其必然发展趋势与要求,然而超高压化会造成其中关键的柱塞副摩擦界面油膜形成显著的固液耦合作用,对柱塞副油膜的摩擦润滑与密封承载性能产生规律尚不明确的影响。为此,建立一种基于变形矩阵法的固液耦合作用求解方法,该方法基于有限容积法解算油膜流体润滑方程,基于有限元法实现摩擦界面变形计算节点规则化设置及变形矩阵精准计算,在此基础上建立柱塞副油膜弹性流体动压润滑数值计算模型,针对采用软硬配对的柱塞副63 MPa超高压工况下的摩擦界面油膜固液耦合作用特性进行研究,结果表明：固液耦合作用有助于减小柱塞副处轴向黏性摩擦力和泄漏流量,一个周期内柱塞副总周向黏性摩擦力大小基本不变但分布更为集中,导致产生了更大峰值的瞬时摩擦力;显著的结构变形产生于柱塞副摩擦界面两端局部位置处,因而对泄漏流量不造成影响,在超高压工况下经过软硬配对跑合,固液耦合作用有助于原本标准柱形铜套孔形成类似“喇叭口”的一种微观形貌,增大了柱塞与铜套孔的接触面积,增强了密封超高压油的能力,降低了接触应力。建立的模型及研究结果可为轴向柱塞泵超高压化设计提供指导。     

热流固耦合下柱塞泵配流副参数对摩擦性能的影响

为探讨热流固耦合下柱塞泵配流副参数对摩擦性能的影响,建立配流副的润滑模型,采用有限差分法对雷诺方程、能量方程和弹性变形方程进行求解,考虑黏度-温度、黏度-压力的关系,利用松弛迭代法求得热流固耦合下油膜压力、弹性变形与油膜温度分布的数值解,并运用MATLAB得到油膜压力、弹性变形、油膜温度分布云图;分析配流副参数对油膜承载力、摩擦力、摩擦转矩和摩擦因数的影响。结果表明：缸体倾斜角度和初始油膜厚度对油膜承载力的影响较大,增大缸体倾斜角度和减小初始油膜厚度,可提高油膜承载能力;减小润滑油黏度、增大初始油膜厚度能有效降低润滑摩擦过程中的摩擦力和摩擦因数。     

表面粗糙度对配流副润滑特性的影响

为研究表面粗糙度对轴向液压柱塞泵马达配流副润滑特性的影响,引入Weierstrass-Mandelbort分形函数,对不同幅值的表面粗糙度的表面形貌进行二维和三维模拟,建立考虑表面粗糙度的流固热耦合下的配流副油膜润滑模型,采用中差分形式的有限差分法和松弛迭代法对其进行数值求解,并分析油膜厚度、油膜压力、油膜承载力、摩擦因数等性能参数随着表面粗糙度幅值变化的规律。通过盘-盘形式的配流盘-缸体摩擦磨损试验,得到不同幅值的表面粗糙度下配流副摩擦因数,对所建立的数学模型进行验证。数值计算结果表明,表面粗糙度幅值的增大会引起油膜承载力增大,但也会引起最大油膜压力和摩擦因数的增大,导致摩擦性能下降。摩擦磨损试验发现,表面粗糙度增大,配流盘表面摩擦磨损情况加剧,配流副润滑性能和耐磨性能整体降低。因此在配流盘表面加工处理中,应适当降低其表面粗糙度。     

Experimental Research on the Dynamic Lubricating Performance of Slipper/Swash Plate Interface in Axial Piston Pumps

The interface between the slipper/swash plate is one of the most important frication pairs in axial piston pumps. The test of this interface in a real pump is very challenging. In this paper, a novel pump prototype is designed and a test rig is set up to study the dynamic lubricating performance of the slipper/swash-plate interface in axial piston machines. Such an experimental setup can simulate the operating condition of a real axial piston pump without changing the relative motion relationship of the interfaces. Considering the lubricant oil film thickness as the main measurement parameter, the attitude of the slipper under the conditions of different load pressure, rotation speed and charge pressure are studied experimentally. After the test, the wear state of the swash plate is observed. According to the friction trace on the surface of the swash plate, the prediction for the attitude of the slipper and the zone easy to wear are verified.     

A11VLO190轴向柱塞泵柱塞副泄漏与润滑特性研究

将轴向柱塞泵柱塞副的泄漏看做偏心圆环缝隙的流动,使用Matlab进行仿真,分析得到了柱塞副泄漏量与负载压力、配合间隙、工作转速和斜盘倾角的关系。采用有限差分法求解二维雷诺方程,该文在考虑油膜动压效应和挤压效应的条件下,得到了柱塞在缸体内的倾角、柱塞自转速度、进口压力对柱塞副油膜分布压力的影响,为提高柱塞副的效率、改善润滑、减少摩擦磨损和增加使用寿命提供了一些参考意见。     

斜盘泵滑靴副剧烈磨损过程的油膜润滑特性分析

斜盘泵滑靴副在发生剧烈磨损过程中,滑靴和斜盘将处于边界润滑状态,油膜润滑特性将发生较大的变化。为此,基于弹性流体动力润滑理论,结合滑靴副的实际工况,推导出滑靴副在剧烈磨损过程中的稳态等温线接触混合弹流润滑基本方程,并建立相应的数学模型。对模型进行数值求解,分析得出滑靴和斜盘接触区油膜压力、油膜厚度与泵转速和外载荷的关系。为斜盘泵滑靴磨损故障程度的影响因素分析及液压泵健康状态评估方法的研究奠定理论基础。     

Lubrication characteristics analysis of slipper bearing in axial piston pump considering thermal effect

In this study, the lubrication characteristics of a slipper bearing for axial piston pump considering oil thermal effect have been investigated. A mathematical model is developed to predict the film thickness and temperature on the slipper/swash plate interface under different operating conditions. Based on the mathematical model, a parametric study is conducted to evaluate the slipper lubrication performance. It is found that the slipper is characterised by an unstable behaviour and the behaviour is enhanced by lower pressure and higher rotational speed. As the film temperature increases rapidly due to high shaft speed and piston chamber pressure, the overall result is a rather low decline in the film thickness. The leakage flow rate increases with increasing speed or oil film thickness. The structure parameter can be optimised to obtain satisfactory slipper performance. Copyright © 2015 John Wiley & Sons, Ltd.     

Dynamic Modeling of Floating Valve Plate Motion in an Axial Piston Pump

The objectives of this study were to analytically and experimentally investigate the motion of the floating valve plate in an axial piston pump under various operating conditions. To achieve the objectives of the analytical investigation, the equations of motion for the valve plate were coupled with a time-dependent lubrication model. The balance pistons that support the floating valve plate were represented by equivalent spring and dashpot systems. The system of equations was then solved using the Runge-Kutta and the control volume finite difference methods to determine the pressure, film thickness, and motion of the valve plate for various operating conditions. To achieve the experimental objectives, a previously developed axial piston pump test rig was instrumented with proximity probes to measure the motion of the valve plate. The stiffness and damping of the balance pistons supporting the floating valve plate were determined using the impact and frequency response methods. Using the experimentally determined stiffness and damping coefficients in the coupled dynamic lubrication model, the analytical and experimental results of the valve plate motions were compared. The model was then used to conduct a parametric study to determine the overall system stiffness and damping coefficients during pump operation. Using the stiffness and damping coefficients from the parametric study in the dynamic lubrication model, the pressure, film thickness, and motion of the valve plate were calculated for various operating conditions. The experimental and analytical displacements of the valve plate were then corroborated and found to be in good agreement.