摘要
叶片泵对油液的清洁度要求较高,油液中混入的少量固体颗粒会引起泵内部摩擦副磨损而使其间隙增大,影响叶片泵的容积效率。为了探明颗粒在叶片泵配流副油膜内部的分布状态及其对配流副损坏机制,该研究使用理论分析、数值模拟和试验测试的方法,研究油液中的固体颗粒对高压叶片泵配流副油膜特性的影响。应用Fluent内置的两相流模型,分别改变固体颗粒直径(0.5~13μm)和固相体积分数(0.2%~1%)、泵的工作压力和转速,开展子母叶片泵配流副油膜内部的固相体积分数分布与温度分布的数值模拟,并对数值模拟结果进行验证。结果表明,油液中的固体颗粒基本不影响配流副油膜的压力数值及其分布,但会引起排油区的油膜温度降低。随着颗粒直径的增大,吸油区油膜固相体积分数减小,最大变化量为0.25%,排油区油膜固相体积分数增大,最大变化量为0.35%,油膜固相体积分数整体上呈增大趋势变化。叶片泵容积效率随着固体颗粒直径的增大而下降,二者近似线性关系。随着颗粒固相体积分数的增加,油膜固相体积分数整体呈增大的趋势变化,最大变化量为0.72%,引起叶片泵容积效率下降,且颗粒固相体积分数与容积效率之间呈非线性关系。油膜表面的温度随颗粒固相体积分数的增加而减小,吸油区各区域油膜温度变化较小,排油区油膜温度最大变化量为2K。配流副油膜受压差流影响较大的区域内固相体积分数随工作压力升高而减小,最大变化量为0.3%,油膜表面各区域的温度有所上升,核心区域温度变化量为4K。油膜大部分区域的油膜固相体积分数和温度都随着泵转速的增大而增大,影响较大的区域中固相体积分数最大变化量为0.2%,温度最大变化量为3 K。研究结果可为高压叶片泵配流副的设计提供参考。
In order to improve the friction characteristics of the friction pair,find the flow state of particles in the oil film and the temperature distribution of oil film in flow distribution pair,the effects of solid particles in the oil on the oil film characteristics and volumetric efficiency of high-pressure vane pump were studied by means of theoretical analysis,numerical simulation and experimental test in this paper.Firstly,the two-phase flow calculation model was established,and the particle gravity equation and motion resistance equation were established also.Then,the passage model of flow distribution pair was set.The fluid domain of flow distribution pair included the oil port,groove and oil film.The passage model was meshed and the boundary conditions were set.According to the relevant standard of cleanliness requirement of hydraulic fluid system,the solid particle diameter was selected as 0.005,0.010 and 0.013 mm,and the solid-phase volume fraction was selected as 0.2%,0.6%and 1%for calculation.Finally,the influnce of solid particle diameter,solid-phase volume fraction and operating parameters on the flow field characteristics of oil film were analysed by FLUENT software.By changing the diameter and solid-phase volume fraction of solid particles,the working pressure and rotating speed of the pump,the nephogram of solid-phase volume fraction distribution and temperature distribution of the oil film in the flow distribution pair were obtained by numerical simulation and verified by test.The result showed the addition of solid particles in the oil had no effect on the pressure value and distribution of the oil film,but it leaded to the decrease of the oil film temperature in the oil discharge area,and the maximum change of oil film temperaturewas 2 K.The solid-phase volume fraction of oil film in the oil suction area decreased with the increase of particle diameter with the maximum change of 0.25%,while it increased in the oil discharge area with the maximum change of 0.35%.On the whole,the solid-phase volume fraction of oil film changed in the increasing trend,and the maximum change was 0.72%.The volumetric efficiency of vane pump decreased with the increase of solid particle diameter,and the relationship between them was approximately linear.With the increase of the solid-phase volume fraction of solid particles,the solid-phase volume fraction of oil film increased,which resulted in the decrease of volumetric efficiency of vane pump.The relationship between solid-phase volume fraction and volumetric efficiency was nonlinear.The surface temperature of oil film decreased with the increase of solid-phase volume fraction.The position of maximum change of oil film temperature was oil discharge area,and the maximum change was 2K.The solid-phase volume fraction of oil film decreased with the increase of working pressure,and the maximum change was 0.3%.The temperature of all areas on the surface of the oil film was increased,and the temperature change of the core area was 4K.The solid-phase volume fraction and temperature in most areas of oil film increased with the increase of rotating speed.The maximum change of solid-phase volume fraction and temperature of oil film was 0.2%and 3 K respectively in the areas with great effect.This research provides a reference for the flow distribution pair design of the port pair of high-pressure vane pump when the oil contains solid particles.
作者
李少年
张磊
常露丹
王煜
代鹏云
Li Shaonian;Zhang Lei;Chang Ludan;Wang Yu;Dai Pengyun(College of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2020年第19期38-49,共12页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金资助项目(51565026)。
关键词
泵
压力
温度
数值模拟
油膜
固体颗粒
pump
pressure
temperature
numerical simulation
oil film
solid particle