液压油物性参数对柱塞副润滑特性的影响

孙光明^1,2，孙健³，李国祥^1*，白书战¹，郑亮¹，师广强²

1.山东大学核科学与能源动力学院，山东 济南  250061；

2.内燃机与动力系统全国重点实验室，山东 潍坊  261061；

3.重油高科电控燃油喷射系统（重庆）有限公司，重庆  401329

摘要：为研究液压油物性参数对柱塞泵柱塞副油膜压力、表面弹性变形、黏性摩擦力、液压油泄漏的影响规律，建立轴向柱塞副油膜压力方程和厚度方程，利用交错网格法对油膜进行离散，利用MATLAB和Abaqus软件分别求解油膜压力和厚度、柱塞副表面弹性变形，采用Python编程，进行MATLAB和Abaqus间数据的实时交换，实现柱塞副油膜进行流-固耦合计算；建立柱塞副油液简化刚度模型和Roelands黏温-黏压方程，分析柱塞副油液刚度和黏度对柱塞副油膜润滑特性的影响。结果表明：油膜刚度对柱塞副油膜压力的影响较大，油膜刚度由29 420 N/mm增大至46 667 N/mm，排油区柱塞副油膜平均峰值压力由208.24 MPa增大至259.93 MPa，但油膜刚度对柱塞副表面弹性变形、轴向黏性摩擦力和泄漏的影响较小；液压油黏度对柱塞副油膜压力、黏性摩擦力、泄漏的影响显著，但对柱塞副表面弹性变形影响较小，液压油黏度由0.009 4 Pa·s增大至0.022 5 Pa·s，排油区柱塞副油膜平均峰值压力增大28.4%，吸油区轴向峰值黏性摩擦力增大154.8%，排油区峰值泄漏量降低66.8%。

关键词：润滑特性；轴向柱塞泵；油液刚度；油液黏度

Influence of hydraulic oil physical property parameters on the lubrication characteristics of piston pairs

SUN Guangming^1,2, SUN Jian³, LI Guoxiang^1*, BAI Shuzhan¹, ZHENG Liang¹, SHI Guangqiang²

1.School of Nuclear Science, Energy and Power Engineering, Shandong University, Jinan 250061, China;

2. State Key Laboratory of Engine and Powertrain System, Weifang 261061, China;

3. Chongyou Hi-Tech Electronic Fuel Injection System (Chongqing) Co., Ltd., Chongqing 401329, China

Abstract: To investigate the effects of hydraulic oil physical property parameters on the oil film pressure, surface elastic deformation, viscous friction, and hydraulic oil leakage of the piston pair, an axial piston pair oil film pressure equation and thickness equation are established. The oil film is discretized using the staggered grid method, and the oil film pressure, thickness, and surface elastic deformation of the piston pair are solved using MATLAB and Abaqus software, respectively. Python programming is used for real-time data exchange between MATLAB and Abaqus, achieving fluid solid coupling calculation of the piston pair oil film. A simplified stiffness model and Roelands viscosity temperature viscosity pressure equation for piston pair oil are established, and the influence of piston pair oil stiffness and viscosity on the lubrication characteristics of piston pair oil film are analyzed. The results show that the oil film stiffness has a significant impact on the oil film pressure of the piston pair. The oil film stiffness increases from 29 420 N/mm to 46 667 N/mm, and the average peak pressure of the piston pair oil film in the oil discharge are increases from 208.24 MPa to 259.93 MPa. However, the effect of the oil film stiffness on the surface elastic deformation, axial viscous friction force, and leakage of the piston pair is relatively small. The viscosity of hydraulic oil has a significant impact on the oil film pressure, viscous friction force, and leakage rate of the piston pair, but has little effect on the elastic deformation of the piston pair surface. The viscosity of hydraulic oil increases from 0.009 4 Pa·s to 0.022 5 Pa·s, and the average peak pressure of the piston pair oil film in the oil discharge are increases by 28.4%. The axial peak viscous friction force in the oil suction are increases by 154.8%, and the peak leakage rate in the oil discharge are decreases by 66.8%.

Keywords: lubrication characteristics; axial piston pump; oil stiffness; oil viscosity