We have reported unique studies on droplet dynamics by addressing complex electro-physical and interfacial interactions. For instance, we have discovered a non-intuitive and remarkably controllable lateral migration of a drop when a uniform electric field, neither parallel nor orthogonal to an imposed hydrodynamic flow, is applied. We attribute this to a non-linear interplay of charge convection and shape deformation to contribute to this symmetry breaking mechanism. We have further brought out an exclusive mechanism of cross-stream migration of a droplet in a confined passage as mediated by surfactant-induced interactions, despite the application of only stream-wise temperature gradient. We have also shown that such surfactant gradients may also induce an increase in the effective viscosity of a dilute emulsion.

References

• A. Poddar, S. Mandal, A. Bandopadhyay, S. Chakraborty, “Electrical switching of a surfactant coated dropin Poiseuille flow”, Journal of Fluid Mechanics (Accepted for publication)
• S. Santra, D. Sen, S. Das, S. Chakraborty, “Electrohydrodynamic interaction between droplet pairs in a confined shear flow”, Physics of Fluids (Accepted for publication)
• S. Santra, S. Mandal, S. Chakraborty, “Electrohydrodynamics of confined two-dimensional liquid droplets in uniform electric field “, Physics of Fluids, vol. 30, pp. 062003(1-17), 2018
• A. Poddar, S. Mandal, A. Bandopadhyay, S. Chakraborty, “Sedimentation of a surfactant-laden drop under the influence of an electric field”, Journal of Fluid Mechanics, vol. 849, pp. 277-311, 2018
• S. Mandal, S. Sinha, A. Bandopadhyay and S. Chakraborty, “Drop deformation and emulsion rheology under the combined influence of uniform electric field and linear flow”, Journal of Fluid Mechanics, vol. 841, pp. 408-433, 2018
• S. Santra, S. Mandal, S. Chakraborty, “Electrohydrodynamics of confined two-dimensional liquid droplets in uniform electric field “, Physics of Fluids, vol. 30, pp. 062003(1-17), 2018
• S. Mandal, S. Chakraborty, “Effect of uniform electric field on the drop deformation in simple shear flow and emulsion shear rheology”, Physics of Fluids, vol. 29, pp. 072109(1-14), 2017
• S. Mandal, S. Chakraborty, “Uniform electric-field-induced non-Newtonian rheology of a dilute suspension of deformable Newtonian drops”, Physical Review Fluids, vol. 2, pp. 093602, 2017
• S. Das, S. Mandal, S. Chakraborty, “Cross-stream migration of a surfactant-laden deformable droplet in a Poiseuille flow”, Physics of Fluids, vol. 29, 082004 (1-22), 2017
• S. Mandal, S. Chakrabarti, S. Chakraborty, “Effect of nonuniform electric field on the electrohydrodynamic motion of a drop in Poiseuille flow”, Physics of Fluids, vol. 29, pp. 052006 (1-16), 2017
• R. Paul, G. N. Kumar, S. Mandal, N.K. Kishore, S. Pramanik, S. Chakraborty, “An Experimental study of the Electrohydrodynamic characteristics of Sedimenting Drops under Uniform Alternating Electric Fields”, IEEE Transactions on Industrial Applications, vol. 53, pp. 5838 – 5844, 2017
• S. Mandal, A. Bandopadhyay, S. Chakraborty, “The effect of surface charge convection and shape deformation on the settling velocity of drops in nonuniform electric field”, Physics of Fluids, vol. 29, pp 012101 (1-21), 2017
• S. Das, S. Mandal, S. K. Som, S. Chakraborty, “Effect of interfacial slip on the deformation of a viscoelastic drop in uniaxial extensional flow field”, Physics of Fluids, vol. 29, pp. 032105 (1-15), 2017
• S. Das, S. Mandal, S. K. Som, S. Chakraborty, “Migration of a surfactant-laden droplet in non-isothermal Poiseuille flow”, Physics of Fluids, vol. 29, pp. 012002 (1-16), 2017
• S. Mandal, A. Bandopadhyay, S. Chakraborty, “The effect of uniform electric field on the cross-stream migration of a drop in plane Poiseuille flow”, Journal of Fluid Mechanics, vol. 809, pp. 726-774, 2016
• S. Mandal, U. Ghosh, S. Chakraborty, Effect of Surfactant on Motion and Deformation of Compound Droplets in Arbitrary Unbounded Stokes Flows, Journal of Fluid Mechanics, vol. 803, pp. 200-249, 2016
• S. Mandal, A. Bandopadhyay, S. Chakraborty, “Dielectrophoresis of a surfactant-laden viscous drop”, Physics of Fluids, vol. 28, pp. 062006(1-29), 2016
• S. Mandal, A. Bandopadhyay, S. Chakraborty, “Effect of surface charge convection and shape deformation on the dielectrophoretic motion of a liquid drop”, Physical Review E, vol. 93, pp. 043127 (1-21), 2016
• A. Bandopadhyay, S. Mandal, N. K. Kishore, S. Chakraborty, “Uniform electric-field-induced lateral migration of a sedimenting drop”, Journal of Fluid Mechanics, vol. 72, pp. 553-589, 2016
• K. Chaudhury, S. Mandal, S. Chakraborty, “Droplet migration characteristics in confined oscillatory microflows”, Physical Review E, vol. 93, pp. 023106 (1-18), 2016
• S. Mandal, A. Bandopadhyay, S. Chakraborty, “Effect of interfacial slip on the cross-stream migration of a drop in an unbounded Poiseuille flow”, Physical Review E, vol. 92, pp. 023002 (1-16), 2015
• S. Mandal, K. Chaudhury, S. Chakraborty, “Transient dynamics of confined liquid drops in a uniform electric field”, Physical Review E, vol. 89, pp. 053020 (1-17), 2014