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建立了不可压缩双重乳液界面行为的理论模型,并可视化实验验证了所建立模型的正确性.基于所建立的理论模型,数值模拟研究了剪切流场中双重乳液的形变机理,探讨了内外液滴半径比及各相工质黏度对其形变特性的影响规律.研究结果表明:在剪切流场中,双重乳液的稳态形变程度随着毛细数的增大而加剧,且内液滴抗形变能力比外液滴更强;随着内外液滴半径比的增大,双重乳液内外液滴间相互作用增强,导致内液滴形变程度增大,同时内液滴抗形变效应逐渐凸显,造成外液滴形变程度减小;双重乳液自身黏性是液滴形变的一种阻力,随着内、外液滴黏度的升高,双重乳液整体形变程度均减小,并且乳液外液滴相黏度变化对双重乳液稳态形变程度的影响更为明显.The manipulation of double emulsion droplet via shear flow field is widely encountered in microfluidic devices. However, the interface evolution and hydrodynamics behavior of double emulsion droplet in shear flow is less understood till now. In this paper, a theoretical model of double emulsion droplet in a Couette flow device is developed and numerically analyzed to characterize the interface behavior of incompressible double emulsion droplet, which is also verified by a visualization experiment. Based on this model, the mechanisms underlying the steady deformation of double emulsion droplet under shear are investigated, and the effects of radius ratio of inner droplet to the outer one and viscosities of working fluids on the steady deformation are discussed. The results indicate that the steady deformation of double emulsion droplet in the shear increases with the rise in capillary number, and the deformation resistance of inner droplet is larger than that of the outer droplet. With increasing the radius ratio of inner droplet to the outer one, the interaction between the inner and outer droplets becomes great and thus the deformation degree of the inner droplet is increased. In addition, the effect of big deformation resistance by the inner droplet tends to be obvious, leading to decreasing the deformation degree of outer droplet. The viscosities of both inner and outer droplets provide a resistance for the deformation of double emulsion droplet. With the rises in viscosities of inner and outer droplets, the deformation degree of integral double emulsion droplet decreases. In addition, the effect of outer droplet viscosity on the steady deformation is more obvious than that of the inner droplet.
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Keywords:
- double emulsion droplet /
- shear flow /
- deformation characteristics /
- visualization
[1] Lee D, Weitz D A 2008 Adv. Mater. 20 3498
[2] Shum H C, Zhao Y J, Kim S H, Weitz D A 2011 Angew. Chem. Int. Ed. 123 1686
[3] Zhao Y J, Zhao X W, Hu J, Xu M, Zhao W J, Sun L G, Zhu C, Xu H, Gu Z Z 2009 Adv. Mater. 21 569
[4] Bychkov V, Modestov M, Law C K 2015 Prog. Energy Combust. Sci. 47 32
[5] Moreau L, Levassort C, Blondel B, de Nonancourt C, Croix C, Thibonnet J, Balland-Longeau A 2009 Laser Part. Beams 27 537
[6] Xu W, Lan Z, Peng B L, Wen R F, Ma X H 2015 Acta Phys. Sin. 64 216801 (in Chinese)[徐威, 兰忠, 彭本利, 温荣福, 马学虎2015物理学报64 216801]
[7] Huang H, Hong N, Liang H, Shi B C, Chai Z H 2016 Acta Phys. Sin. 65 084702 (in Chinese)[黄虎, 洪宁, 梁宏, 施保昌, 柴振华2016物理学报65 084702]
[8] Mei M F, Yu B M, Luo L, Cai J C 2010 Chin. Phys. Lett. 27 076862
[9] Stone H A 1994 Annu. Rev. Fluid Mech. 26 65
[10] Renardy Y 2008 Int. J. Multiphase Flow 34 1185
[11] Guido S 2011 Curr. Opin. Colloid Interface Sci. 16 61
[12] Sibillo V, Pasquariello G, Simeone M, Cristini V, Guido S 2006 Phys. Rev. Lett. 97 054502
[13] Smith K A, Ottino J M, de la Cruz M O 2004 Phys. Rev. Lett. 93 204501
[14] Hua H, Shin J, Kim J 2014 Int. J. Heat Fluid Flow 50 63
[15] Patlazhan S, Vagner S, Kravchenko I 2015 Phys. Rev. E 91 063002
[16] Wang J T, Liu J X, Han J J, Guan J 2013 Phys. Rev. Lett. 110 066001
[17] Gao P, James J F 2011 J. Fluid Mech. 682 415
[18] Brackbill J U, Kothe D B, Zemach C A 1992 J. Comput. Phys. 100 335
[19] Hirt C W, Nichols B D 1981 J. Comput. Phys. 46 201
[20] Renardy Y, Cristini V 2001 Phys. Fluids 13 2161
[21] Taylor G I 1934 Proceedings of the Royal Society of London Series A 146 501
[22] Chen Y P, Wu L Y, Zhang L 2015 Int. J. Heat Mass Transfer 82 42
[23] Stone H A, Leal L G 1990 J. Fluid Mech. 211 123
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[1] Lee D, Weitz D A 2008 Adv. Mater. 20 3498
[2] Shum H C, Zhao Y J, Kim S H, Weitz D A 2011 Angew. Chem. Int. Ed. 123 1686
[3] Zhao Y J, Zhao X W, Hu J, Xu M, Zhao W J, Sun L G, Zhu C, Xu H, Gu Z Z 2009 Adv. Mater. 21 569
[4] Bychkov V, Modestov M, Law C K 2015 Prog. Energy Combust. Sci. 47 32
[5] Moreau L, Levassort C, Blondel B, de Nonancourt C, Croix C, Thibonnet J, Balland-Longeau A 2009 Laser Part. Beams 27 537
[6] Xu W, Lan Z, Peng B L, Wen R F, Ma X H 2015 Acta Phys. Sin. 64 216801 (in Chinese)[徐威, 兰忠, 彭本利, 温荣福, 马学虎2015物理学报64 216801]
[7] Huang H, Hong N, Liang H, Shi B C, Chai Z H 2016 Acta Phys. Sin. 65 084702 (in Chinese)[黄虎, 洪宁, 梁宏, 施保昌, 柴振华2016物理学报65 084702]
[8] Mei M F, Yu B M, Luo L, Cai J C 2010 Chin. Phys. Lett. 27 076862
[9] Stone H A 1994 Annu. Rev. Fluid Mech. 26 65
[10] Renardy Y 2008 Int. J. Multiphase Flow 34 1185
[11] Guido S 2011 Curr. Opin. Colloid Interface Sci. 16 61
[12] Sibillo V, Pasquariello G, Simeone M, Cristini V, Guido S 2006 Phys. Rev. Lett. 97 054502
[13] Smith K A, Ottino J M, de la Cruz M O 2004 Phys. Rev. Lett. 93 204501
[14] Hua H, Shin J, Kim J 2014 Int. J. Heat Fluid Flow 50 63
[15] Patlazhan S, Vagner S, Kravchenko I 2015 Phys. Rev. E 91 063002
[16] Wang J T, Liu J X, Han J J, Guan J 2013 Phys. Rev. Lett. 110 066001
[17] Gao P, James J F 2011 J. Fluid Mech. 682 415
[18] Brackbill J U, Kothe D B, Zemach C A 1992 J. Comput. Phys. 100 335
[19] Hirt C W, Nichols B D 1981 J. Comput. Phys. 46 201
[20] Renardy Y, Cristini V 2001 Phys. Fluids 13 2161
[21] Taylor G I 1934 Proceedings of the Royal Society of London Series A 146 501
[22] Chen Y P, Wu L Y, Zhang L 2015 Int. J. Heat Mass Transfer 82 42
[23] Stone H A, Leal L G 1990 J. Fluid Mech. 211 123
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