Double-diffusive lock-exchange gravity currents
نویسندگان
چکیده
The dynamics of double-diffusive gravity currents exhibiting the fingering instability were examined using 2D and 3D simulations of a lock exchange initial configuration. It was found that although the spreading of the currents was governed by a balance of buoyancy and turbulent drag forces, currents with more intense fingering spread faster than those with less intense or no fingering. This was due to an increase in the buoyancy of the currents with stronger fingering, which had a stronger effect than the increased drag. The fingering also affected the thickness of the currents, with more fingering corresponding to thinner currents. We found that in 3D, fluxes were higher than in 2D, so that currents with the same parameters exhibited the effects of stronger fingering in 3D.
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