ACTA AERONAUTICAET ASTRONAUTICA SINICA >
State identification and characteristics analysis of oil droplet's oblique impact onto solid wall
Received date: 2014-06-04
Revised date: 2014-06-23
Online published: 2014-07-09
Analysis of oil/air two-phase flow and heat transfer in bearing chamber are important fundamental work for the lubrication and heat transfer design of aeroengine bearing chamber, while state identification and characteristics analysis of oil droplet's oblique impact onto solid wall are the main parts for oil/air two-phase flow and heat transfer study. In this paper, the numerical model of oil droplet's oblique impact onto solid wall is established with volume of fluid (VOF) method and the numerical simulation of oil droplet impingement state is carried out, and then the effects of oil droplet diameter, incident angle, impact velocity on the deposited oil film spreading length, oil film thickness and splashing droplets number are discussed particularly, the criterion used for classify impingement state of oil droplet oblique impingement is proposed, and its rationality is verified by physical testing work of others. The results show that as the incident angle decreases, the deposited oil film spreading length and oil film thickness increase, whereas the number of splashing droplets reduces; as the impact velocity and oil droplet diameter increase, the deposited oil film spreading length and the splashing droplets number increase, but the oil film thickness decreasing trend corresponds to the former and the increasing trend corresponds to the latter.
Key words： aeroengine; bearing chamber; oil droplet; oblique impact; numerical simulation; criterion
LIU Deng , CHEN Guoding , FANG Long , SUN Hengchao . State identification and characteristics analysis of oil droplet's oblique impact onto solid wall[J]. ACTA AERONAUTICAET ASTRONAUTICA SINICA, 2015 , 36(4) : 1359 -1366 . DOI: 10.7527/S1000-6893.2014.0134
[1] Mundo C, Sommerfeld M, Tropea C. Droplet wall collisions: experimental studies of the deformation and breakup process[J]. International Journal of Multiphase Flow, 1995, 2l(2): 151-173.
[2] Rioboo R, Tropea C, Marengo M. Outcomes from a drop impact on solid surfaces[J].Atomization and Sprays, 2001, 11(2): 155-165.
[3] Rioboo R, Marengo M, Tropea C. Time evaluation of liquid drop impact onto solid dry surfaces[J]. Experimental Fluids, 2002, 33(2): 112-121.
[4] Sikalo S, Tropea C, Ganic E N. Impact of droplets onto inclined surfaces[J]. Journal of Colloid and Interface Science, 2005, 286(4): 661-669.
[5] Sikalo S, Ganic E N. Phenomena of droplet-surface interactions[J]. Experimental Thermal and Fluid Science, 2006, 31(1): 97-110.
[6] Hitoshi F, Yu S. Three-dimensional numerical analysis of the deformation state of droplets impinging onto a solid substrate[J]. International Journal of Multiphase Flow, 2007, 33(3): 317-332.
[7] Shen S Q, Cui Y Y, Guo Y L. Numerical simulation of droplet striking on inclined isothermal surface[J]. Journal of Thermal Science and Technology, 2009, 8(3): 194-197 (in Chinese). 沈胜强, 崔艳艳, 郭亚丽. 液滴撞击等温斜面的数值模拟[J]. 热科学与技术, 2009, 8(3): 194-197.
[8] Cui Y Y. Research on dynamical process of droplet impacting on inclined surface[D]. Dalian: Dalian University of Technology, 2010 (in Chinese). 崔艳艳. 液滴撞击倾斜壁面动力学过程研究[D]. 大连: 大连理工大学, 2010.
[9] Lu J J, Chen X L, Cao X K, et al. Characteristic phenomenon and analysis of a single liquid droplet impacting on dry surfaces[J]. Chemical Reaction Engineering and Technology, 2007, 23(6): 505-510 (in Chinese). 陆军军, 陈雪莉, 曹显奎, 等. 液滴撞击平板的铺展特征[J]. 化学反应工程与工艺, 2007, 23(6): 505-510.
[10] Song Y C. Fundamental study on the interface tracking method of gas-liquid two-phase flows and droplet impacting onto the surface[D]. Beijing: Beijing Jiaotong University, 2012 (in Chinese). 宋云超. 气液两相流动相界面追踪方法及液滴撞击壁面运动机制的研究[D]. 北京: 北京交通大学, 2012.
[11] Hirt C W, Nichols B D. Volume of fluid (VOF) method for the dynamics of free boundaries[J]. Journal of Computational Physics, 1981, 39(2): 201-225.
[12] Brackbill J U, Kothe D B, Zemach C. A continuum method for modeling surface-tension[J]. Journal of Computational Physics, 1992, 100(2): 335-354.
[13] Lunkad S F, Buwa V V, Nigam K. Numerical simulations of drop impact and spreading on horizontal and inclined surfaces[J]. Chemical Engineering Science, 2007, 62(4): 7214-7224.
[14] Scheller B L, Bousfield D W. Newtonian drop impact with solid surface[J]. American Institute of Chemical Engineers, 1995, 41(3): 1357-1362.
[15] Zhang X G, Basaran O A. Dynamic surface tension effect in impact of a drop with a solid surface[J]. Colloid Interface Science, 1997, 187(2): 166-175.
[16] Wang J, Chen G D, Liu Y J. Analysis of the oil droplet motion and deposition characteristics in an aero-engine bearing chamber[J]. Tribology, 2010, 30(4): 362-366 (in Chinese). 王军, 陈国定, 刘亚军. 航空发动机轴承腔中油滴运动与沉积的特性分析[J]. 摩擦学学报, 2010, 30(4): 362-366.
[17] Chen B, Chen G D, Wang T. Flow characteristics analysis of wall oil film with consideration of oil droplet deformation and secondary oil droplet deposition in aeroengine bearing chamber[J]. Acta Aeronautica et Astronautica Sinica, 2013, 34(8): 1980-1989 (in Chinese). 陈薄, 陈国定, 王涛. 考虑油滴变形和二次油滴效应的轴承腔壁面油膜流动分析[J].航空学报, 2013, 34(8): 1980-1989.
[18] Pan K L, Tseng K C, Wang C H . Breakup of a droplet at high velocity impacting a solid surface[J]. Experiment Fluids, 2010, 48(2): 143-156.
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