Reshaping Capillary Rise


Shaping to Bounce


Leidenfrost effect on textured surfaces


The spontaneous displacement of one fluid by another has been studied for centuries owing to its importance in a variety of applications ranging from oil recovery to paper-based microfluidics. When a gas is spontaneously displaced by a liquid, the dynamics follow the Lucas–Washburn law, which is initially independent of gravitational effects (top image). Our article demonstrates, with theory and experiment, how the early stages of spontaneous capillary rise are reshaped by both viscous and gravitational effects when the displaced phase is no longer negligible (middle and bottom images). The results may find applications ranging from rapid measurements of wettability and porosity to carbon sequestration and the migration of groundwater contaminants. 

Cover Issue: Langmuir Volume 32, Issue 21

We investigate how surface texture can modify the shape of a drop as it impacts a nonwetting surface. In particular, we demonstrate that certain macrotextures can lead to a phenomenon in which the center of the drop assists in the recoil. When these textures are incorporated on non-wetting surfaces, they can significantly reduce the time that the drop is in contact with the surface, effectively keeping the surface drier. 

Press Coverage: New York Times, Boston Globe, Phys Org.

We are interested in the effects of surface texture on how hot a surface must be to float a drop on the it’s own vapor.Press Coverage: Newswise
Rupturing bubbles and thin films

Drop Impact and splashing

Electrocoalescence of conical drops

Small bubbles are important in health, the environment, and in industry in part because the rupture of these bubbles can transfer small droplets into the atmosphere. We are researching how the rupture of large bubbles can create a ring of these smaller bubbles – a phenomenon that can be easily observed in the kitchen sink. Our results have linked these smaller, daughter bubbles to the shape of the larger bubble as it collapses. Movies
Related Publications
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NPR, New York Times, BBC, Boston Globe,
Highlighted in Physics Today/Backscatter
Drops falling on to inclined or moving surface experience a tangential velocity at impact. The tangetial velocity of the surface relative to the drop can trigger or inhibit a splash. In addition to describing asymmetries from tangential velocity, our study provides more general insight into the fundamental mechanisms responsible for splashing on dry, smooth substrates.Related Publications Oppositely charged liquid drops deform into cones as they contact. We are interested in their deformation, as well as the subsequenct behavior after contact. These conical drops fail to coalesce above a critical cone angle, a phenomenon we believe is due to mainly to local geometery. MovieRelated Publications

Press Coverage:
HarvardScience, New Scientist, Physics World

Publication List

Please note: Electronic versions of these papers are provided for academic purposes only. Please do not repost without appropriate permission.

  • McRae O, Gaillard A, & Bird JC. (2017). Periodic jetting and monodisperse jet drops from oblique gas injection. Phys. Rev. E, 96,013112. doi:10.1103/PhysRevE.96.013112
  • Walls, P. L., & Bird, J. C. (2017). Enriching particles on a bubble through drainage: Measuring and modeling the concentration of microbial particles in a bubble film at rupture. Elem Sci Anth, 5. [PDF]
  • Shiri, S., & Bird, J. C. (2017). Heat exchange between a bouncing drop and a superhydrophobic substrate. J. Proc. Natl. Acad. Sci., 201700197. [PDF]
  • Patterson, C. J., Shiri, S., & Bird, J. C. (2016). Macrotextured spoked surfaces reduce the residence time of a bouncing Leidenfrost drop. J. Phys. Condens. Matter 29 (6), 064007.
  • Walls, P. L. L., Dequidt, G., & Bird, J. C. (2016). Capillary displacement of viscous liquids. Langmuir 32 (13), 3186–3190.
  • Walls, P. L. L., Henaux, L., & Bird, J. C. (2015). Jet drops from bursting bubbles: How gravity and viscosity couple to inhibit droplet production. Phys. Rev. E, 92(2), 021002. [PDF]
  • Farmer, T. P., & Bird, J. C. (2015). Asymmetric capillary bridges between contacting spheres. J. Colloid Interf. Sci, 454 (April), 192–199. [PDF]
  • Bartlett, C. T., Généro, G. A., & Bird, J. C. (2014). Coalescence and break-up of nearly inviscid conical droplets. J. Fluid Mech., 763, 369–385. [PDF]
  • Walls, P. L. L., Bird, J. C., & Bourouiba, L. (2014). Moving with Bubbles: A Review of the Interactions between Bubbles and the Microorganisms that Surround them. Integrative and Comparative Biology, 1–12. [PDF]
  • J.C. Bird, R. Dhiman, H. Kwon, & K. K. Varanasi (2013). “Reducing contact time of a bouncing drop.” Nature. 503, 385-388. [PDF]
  • H. Kim, J.C. Bird, K. K. Varanasi (2013) “Increasing the Leidenfrost point using micro-nano hierarchical surface textures.” App. Phys. Lett. 103, 201601. [PDF]
  • N. Meskhidze, et al., (2013) “Production mechanisms, number concentration, size distribution, chemical composition and optical properties of sea spray aerosols” Atmos. Sci. Lett. 14 207-213. [PDF]
  • J.C. Bird, R. de Ruiter, L. Courbin, & H.A. Stone (2010) “Daughter bubble cascades produced by folding of ruptured thin films.” Nature. 465, 759-762. [PDF]
  • L. Courbin, J.C. Bird, M. Reyssat, and H.A. Stone (2009). “Dynamics of wetting: From inertial spreading to viscous imbibition.” J. Phys.: Condens. Matter 21 464127. [PDF]
  • A.C. Rowat, J.C. Bird, J.J. Agresti, O.J. Rando, and D.A. Weitz (2009). “Tracking lineages of cells in lines using a microfluidic device.” Proc. Nat. Acad. Sci. U.S.A. 106:18149-18154. [PDF]
  • J.C. Bird, W. D. Ristenpart, A. Belmonte, and H.A. Stone (2009). “Critical angle for electrically driven coalescence of two conical droplets.” Phys. Rev. Lett. 103, 164502. [PDF]
  • W. D. Ristenpart, J.C. Bird, A. Belmonte, F. Dollar, and H.A. Stone (2009). “Non-coalescence of oppositely charged drops” Nature 461, 377-380. [PDF]
  • J.C. Bird, S.S.H. Tsai, and H.A. Stone (2009). “Inclined to splash: Triggering and inhibiting a splash with tangential velocity.” New J. Phys. 11, 063017. [IOP Select] [PDF]
  • L. Courbin, J.C. Bird, A. Belmonte, and H.A. Stone (2008). “”Black hole” nucleation in a splash of milk” Phys. Fluids 20, 091106. [Winning entry, 2008 Gallery of Fluid Motion] [PDF]
  • J.C. Bird, S. Mandre, and H.A. Stone (2008). “Short-time dynamics of partial wetting.” Phys. Rev. Lett. 100, 234501. [PDF]
  • L. Courbin, J.C. Bird, and H.A. Stone (2006). “Splash and anti-splash: Observation and design.” Chaos 16, 041102. [PDF]
  • M.J. Kim, M.J. Kim, J.C. Bird , J. Park, T.R. Powers, & K.S. Breuer (2004). “Particle Image Velocimetry Measurements on a Macro-scale Model for Bacterial Flagellar Bundling.” Exp. Fluids 37: 782-788. [PDF]
  • G. Han, K.J. Westin, J.C. Bird, Z. Cao, & K.S. Breuer (2004). “Infrared Diagonistics for Measuring Fluid and Solid Motion inside Microdevices.” Microscale Therm. Eng. 8: 169-182. [PDF]
  • M.J. Kim, J.C. Bird, A.J. VanParys, K.S. Breuer, & T.R. Powers (2003). “A macroscopic scale model of bacterial flagellar bundling.” Proc. Nat. Acad. Sci. U.S.A. 100: 15481-15485. [PDF]