摘要
【目的】针对旋转摩擦副在高转速下的油膜空化问题,研究了半球表面织构对空化现象的影响,分析织构边界流场压力与油膜稳定性的关系,以优化润滑性能并减少空化。【方法】结合仿真与试验,分析了表面织构对摩擦润滑特性的影响。首先,建立了多相流模型、湍流模型和空化模型;其次,使用有限元法研究了不同织构率下的空化表现,并进行了空化速度场分析、空化压力场分析和空化质量传递速率分析;最后,搭建了可视化试验平台,使用高速摄像机观察不同转速下有、无织构的对偶片上空化泡发展情况。【结果】仿真和试验结果发现,空化体积分数和织构率并非正相关;空化的发生和溃灭过程极短暂,一旦满足空化条件,在0.015 s内就可产生饱满的空泡;空化区域内气液两相的速度始终保持一致,发现空化发展过程中伴随着气液两相质量传递;验证了空化气体源自于油液的相变,流场中的不平整表面是空化发生的重点诱因;光滑表面不会产生空化,而织构后的摩擦副表面易产生剧烈的空化现象。因此,加工微织构时应优先考虑表面粗糙度及织构分布的位置。
[Objective]This study investigates the effects of hemispherical surface textures on cavitation in high-speed rotating friction pairs,analyzing pressure disturbances at texture boundaries and their impact on oil film stability to enhance lubrication performance and reduce cavitation.[Methods]By combining simulation and test,the influence of surface texture on friction lubrication characteristics was analyzed.Firstly,multiphase flow,turbulence,and cavitation models were established.Then,finite element analysis was conducted to examine cavitation characteristics(velocity field,pressure field,and mass transfer rate)under different texture ratios.Finally,a visualization test platform was built,using high-speed cameras to observe cavitation bubble dynamics on textured and non-textured counterfaces at varying rotational speeds.[Results]Simulation and test results reveal that cavitation volume fraction and texture ratio are not positively correlated.The onset and collapse of cavitation is extremely short,and once the conditions for cavitation are met,full vacuoles can be produced within 0.015 s.The velocities of gas and liquid phases in cavitation region are always the same,and process of occurring cavitation is accompanied by gas-liquid mass transfer.The results verify that the cavitation gas originates from phase transition of liquid;the uneven surface in flow field is the focal trigger for cavitation.Simulation analysis and test results show that smooth surface does not produce cavitation,while the textured surface of the friction sub-surface is prone to intense cavitation.Therefore,surface roughness and location of texture distribution should be given priority when processing microtextures.
作者
文世聪
孙俊雨
石复习
WEN Shicong;SUN Junyu;SHI Fuxi(College of Mechanical and Electronic Engineering,Northwest A&F University,Yangling 712100,China)
出处
《机械传动》
北大核心
2025年第10期113-124,共12页
Journal of Mechanical Transmission
基金
陕西省科技重大专项(2024NC-ZDCYL-05-10)。
关键词
旋转摩擦副
空化
流场
润滑
有限元分析
摩擦
Rotation friction pair
Cavitation
Flow field
Lubrication
Finite element analysis
Friction
