Liquid film thickness model formed by atomized droplets during sustainable cryogenic air MQL grinding  

作　　者：Mingzheng LIU Changhe LI Qinglong AN Yanbin ZHANG Min YANG Xin CUI Teng GAO Yusuf Suleiman DAMBATTA Runze LI 

机构地区：[1]Key Laboratory of Industrial Fluid Energy Conservation and Pollution Control(Ministry of Education),Qingdao University of Technology,Qingdao 266520,China [2]Qingdao Jimo Qingli Intelligent Manufacturing Industry Research Institute,Qingdao 266201,China [3]School of Mechanical Engineering,Dalian University of Technology,Dalian 116081,China [4]Mechanical Engineering Department,Ahmadu Bello University,Zaria 810106,Nigeria [5]School of Engineering,Department of Biomedical Engineering,Massachusetts Institute of Technology,Boston 02139,USA

出　　处：《Frontiers of Mechanical Engineering》2025年第1期45-68,共24页机械工程前沿(英文版)

基　　金：financially supported by the National Natural Science Foundation of China(Grant No.52375447);Shandong Provincial Natural Science Foundation of General Program,China(Grant No.ZR2024ME205);the Special Fund of Taishan Scholars Project,China(Grant No.tsqn202408220);Shandong Provincial Natural Science Foundation of Youth Fund,China(Grant No.ZR2021QE116).

摘　　要：Surface thermal damage in a difficult-to-process metal precision grinding workpiece has emerged as a technical bottleneck restricting machining quality.As an alternative to traditional pouring cooling,a green clean minimum-quantity lubrication technology still has defects,such as insufficient heat dissipation.The use of cryogenic air instead of normal temperature air,that is,the supply of low-temperature energized lubricant,can effectively improve oil film heat transfer and lubrication performance in a grinding area.Under the premise of ensuring the effective flow of lubricating oil in a grinding zone,the thickness of a liquid film in the wedge zone of a grinding wheel or workpiece is the key factor for determining its performance.However,the dynamic mechanism of droplet formation and distribution of liquid film thickness are still unclear.Hence,the mechanism by which nozzle orientation influences the effective region of a liquid film was analyzed,and the range of nozzle inclination that helps to atomize droplets and enables them to enter the grinding zone was revealed.Then,the dynamic mechanism of atomized droplet film formation was analyzed,and the influence of normal and tangential momentum sources generated by gas impingement perturbation flow and droplet impingement steady flow on the driving effect of liquid film flow was revealed.The thickness distribution model of a liquid film in the impact zone of gas–liquid two-phase flow under different cryogenic air temperatures was established.The model results under different working conditions were obtained by numerical analysis,and validation experiments were carried out.Results show that the measured values agree with the theoretical values.At 0.4 MPa air pressure,the thickness of the liquid film in the impact zone of the atomized droplets increases with decreasing cryogenic air temperature.At−10 and−50°C,the thickness of the liquid film is 0.92 and 1.26 mm,respectively.Further,on the basis of the surface topography model of cubic boron nitride grinding w

关 键 词：sustainable grinding cryogenic cooling minimum quantity lubrication CAMQL liquid film thickness formation mechanism 

分 类 号：TG1[金属学及工艺—金属学]