声空化条件下传动液中空气析出与溶解过程的研究  

Process of Air Evolution and Dissolution in Transmission Fluid Under Acoustic Cavitation

作　　者：陈益宏 徐刚强 李孝禄 陈源 李运堂 CHEN Yi-hong;XU Gang-qiang;LI Xiao-lu;CHEN Yuan;LI Yun-tang(College of Mechanical and Electrical Engineering,China Jiliang University,Hangzhou,Zhejiang 310018;Key Laboratory of Intelligent Manufacturing Quality Big Data Tracing and Analysis of Zhejiang Province,China Jiliang University,Hangzhou,Zhejiang 310018;Technology Center,Zhejiang Boxing Industry&Trade Co.,Ltd.,Jinhua,Zhejiang 321016)

机构地区：[1]中国计量大学机电工程学院,浙江杭州310018 [2]浙江省智能制造质量大数据溯源与应用重点实验室,浙江杭州310018 [3]浙江博星工贸有限公司技术中心,浙江金华321016

出　　处：《液压与气动》2022年第9期53-62,共10页Chinese Hydraulics & Pneumatics

基　　金：国家自然科学基金(51675498);浙江省自然科学基金(LY14E050023)。

摘　　要：传动液中空气的析出与溶解影响传动系统的控制精度。传动液起到传递动力的作用,本身会溶解少量空气,溶解的空气随着压力的变化产生溶解和析出过程,破坏了液流的连续性,造成传动性能的下降,甚至影响传动系统的使用寿命。为此,基于斜压流模型,引入气体析出与溶解的气泡模型,建立传动管内的气液两相流含气率模型,考虑空气质量分数和体积分数,得到空化流动相关方程式。采用特征线法和一维有限差分法求解,获得了气液两相流主要参数的变化,包括空气析出与溶解时间常数、压力和温度对含气率的影响,并研究了含气率对体积弹性模量的影响。结果表明:传动管内的传动介质压力越大,空化程度越少;空气析出速率越小,含气率越低。传动介质受压引起其温度的变化;在空化区域,温度变化较小。当传动管内压力高于空气分离压时,传动介质的压力和体积弹性模量随含气率增大而减小;当压力低于空气分离压时,发生空化现象,含气率增加较快,但对体积弹性模量影响较小。The evolution and dissolution of air in transmission fluid affect the control precision of the transmission system. Transmission fluid plays the role of transmission power, but it usually dissolves a small amount of air. The dissolved air with the change of pressure dissolution and evolution process destroys the continuity of liquid flow, resulting in the decline of transmission performance, and even affecting the service life of the transmission system. Therefore, based on the baroclinic flow model, the gas-liquid two-phase flow air volume fraction model in the transmission tube was established by introducing the bubble model of gas evolution and dissolution. Considering the air mass fraction and volume fraction, the related equations of cavitation flow were obtained. The characteristic line method and one-dimensional finite difference method were used to obtain the main parameters of gas-liquid two-phase flow, including the effect of air evolution and dissolution time constant, pressure and temperature on the air volume fraction, and the effect of air volume fraction on the bulk elastic modulus was studied. The results show that the higher the pressure of the transmission medium in the transmission tube, the less the degree of cavitation. The lower the air release rate, the lower the air volume fraction. Transmission medium pressure could cause its temperature change. In the cavitation region, the temperature change was little. When the pressure in the transmission tube was higher than the air separation pressure, the pressure and bulk elastic modulus of the transmission medium decreased with the increase of air volume fraction. When the pressure was lower than the air separation pressure, the cavitation occurred and the air volume fraction increased rapidly, but it had little effect on the bulk elastic modulus.

关 键 词：传动液 气液两相流 声空化 含气率 体积弹性模量 

分 类 号：TH137[机械工程—机械制造及自动化]