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Chin. Phys. B, 2021, Vol. 30(5): 054703    DOI: 10.1088/1674-1056/abd7dd
ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS Prev   Next  

Numerical simulation on partial coalescence of a droplet with different impact velocities

Can Peng(彭灿), Xianghua Xu(徐向华), and Xingang Liang(梁新刚)
Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, School of Aerospace Engineering, Tsinghua University, Beijing 100084, China
Abstract  Partial coalescence is a complicated flow phenomenon. In the present study, the coalescence process is simulated with the volume of fluid (VOF) method. The numerical results reveal that a downward high-velocity region plays a significant role in partial coalescence. The high-velocity region pulls the droplet downward continuously which is an important factor for the droplet turning into a prolate shape and the final pinch-off. The shift from partial coalescence to full coalescence is explained based on the droplet shape before the pinch-off. With the droplet impact velocity increasing, the droplet shape will get close to a sphere before the pinch-off. When the shape gets close enough to a sphere, the partial coalescence shifts to full coalescence. The effect of film thickness on the coalescence process is also investigated. With large film thickness, partial coalescence happens, while with small film thickness, full coalescence happens. In addition, the results indicate that the critical droplet impact velocity increases with the increase of surface tension coefficient but decreases with the increase of viscosity and initial droplet diameter. And there is a maximum critical Weber number with the increase of surface tension coefficient and initial droplet diameter.
Keywords:  droplet impact      partial coalescence      volume of fluid (VOF) method  
Received:  30 July 2020      Revised:  27 November 2020      Accepted manuscript online:  04 January 2021
PACS:  47.61.Jd (Multiphase flows)  
  47.55.df (Breakup and coalescence)  
  47.55.Ca (Gas/liquid flows)  
Fund: Project supported by the National Natural Science Foundation of China (Grant No. 51876102) and the Science Fund for Creative Research Groups of the National Natural Science Foundation of China (Grant No. 51621062).
Corresponding Authors:  Xianghua Xu     E-mail:  xxh@tsinghua.edu.cn

Cite this article: 

Can Peng(彭灿), Xianghua Xu(徐向华), and Xingang Liang(梁新刚) Numerical simulation on partial coalescence of a droplet with different impact velocities 2021 Chin. Phys. B 30 054703

[1] Ikegawa M and Azuma H 2004 International Journal Series B Fluids and Thermal Engineering 47 490
[2] Panão M R O and Moreira A L N 2005 Exp. Fluids 39 364
[3] Aziz S D and Chandra S 2000 Int. J. Heat Mass Transf. 43 2841
[4] Kim J 2007 Int. J. Heat Fluid Flow 28 753
[5] Cheng W L, Zhang W W, Chen H and Hu L 2016 Renew. Sust. Energ. Rev. 55 614
[6] Zhou Z F, Chen B, Wang R, Bai F L and Wang G X 2016 Exp. Therm. Fluid Sci. 70 96
[7] Cossali G E, Marengo M, Coghe A and Zhdanov S 2004 Exp. Fluids 36 888
[8] Guo J H, Dai S Q and Dai Q 2010 Acta Phys. Sin. 59 2601 (in Chinese)
[9] Liang G T and Mudawar I 2016 Int. J. Heat Mass Transf. 101 577
[10] Ray B, Biswas G and Sharma A 2015 J. Fluid Mech. 768 492
[11] Charles G E and Mason S G 1960 J. Colloid Sci. 15 105
[12] Schotland R M 1960 Discuss. Faraday Soc. 30 72
[13] Chen X, Mandre S and Feng J J 2006 Phys. Fluids 18 051705
[14] Blanchette F and Bigioni T P 2006 Nat. Phys. 2 254
[15] Aryafar H and Kavehpour H P 2006 Phys. Fluids 18 072105
[16] Yue P, Zhou C and Feng J J 2006 Phys. Fluids 18 102102
[17] Thoroddsen S T and Takehara K 2000 Phys. Fluids 12 1265
[18] Chen X, Mandre S and Feng J J 2006 Phys. Fluids 18 092103
[19] Gilet T, Mulleners K, Lecomte J P, Vandewalle N and Dorbolo S 2007 Phy. Rev. E 75 036303
[20] Ray B, Biswas G and Sharma A 2010 J. Fluid Mech. 655 72
[21] Mohamed-Kassim Z and Longmire E K 2004 Phys. Fluids 16 2170
[22] Hirt C W and Nichols B D 1981 J. Comput. Phys. 39 201
[23] Brackbill J U, Kothe D B and Zemach C 1992 J. Comput. Phys. 100 335
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