Simulation of bursting bubble
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Rupturing bubbles and thin films Bubble bursting plays a role in health, the environment, and in industry. When a free film ruptures, surface tension causes the film to retract. We are interested in the dynamics away from the rim. |
Splashing controlled
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Drop Impact and splashing 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. |
Geometric noncoalescence
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Electrocoalescence of conical drops 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. Movie |
Early spreading of droplets
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The initial dynamics of partial wetting When a liquid drop contacts a wettable surface, the liquid spreads over the solid to minimize the total surface energy. For perfectly wetting systems, the first moments of spreading are inertially dominated. We demonstrate that even in the presence of a contact line, the initial wetting is dominated by inertia rather than viscosity. Additionally, we find that the spreading radius follows a power-law scaling in time where the exponent depends on the equilibrium contact angle. |
Yeast epigentics
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When expression runs in the family Worked wtih Amy Rowat in developing techniques to track yeast epigentics in microfluid channels. Genetically identical cells are known to exhibit phenotypic variation, especially when stressed. Tracking individual cells and their progeny provides a means to attribute some of this variation to non-genetic characteristics, such as age, number of children, and family lineage. |
Coral bleaching
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Before coming to Harvard, I researched coral bleaching with scientists at the Australian Institute of Marine Science and at James Cook University. Our aim was to model the fluid and thermo- dynamics around a reef system in order to gain insights on the spatial variability of coral bleaching. Coral is comprised of several individual coral polyps that rely on a symbiotic relationship with an alga, zooxanthellae. Under extreme stress, corals will purge the inhabiting zooxanthellae and as a result the corals become white, or bleached. If the coral remains stressed so that zooxanthellae can not return, the coral will die. Abnormally high UV radiation, salinity, or chemical concentrations can all contribute to coral bleaching; however the dominant cause for large-scale bleaching is increased water temperature. Water temperature elevated only one degree Celsius above the maximum monthly average is considered to have reached a bleaching threshold. By modeling the water temperature variation throughout the water column, we have found that we can predict which areas are likely to experience severe bleaching episodes. |
