Author(s): Angelos Kokkinos; Panagiotis Prinos
Linked Author(s): Panagiotis Prinos
Keywords: No Keywords
Abstract: This work presents LES results of two colliding gravity currents in the framework of a lock-release set-up. Gravity currents collision is important in many physical conditions and especially in atmospheric flows such as sea breezes, thunderstorm outflows, katabatic flows, etc. A partial-depth set-up is used a better simulation of the collision in the deep air column of the atmosphere. The numerical model solves the filtered NavierStokes equations in conjunction with a transport equation for the concentration assuming Boussinesq approximation for density. The focus is on the examination of the dynamical features and mixing during collision of gravity currents with varying densities and/or heights. The ratio of the reduced gravities (rg) of the two currents varies from 0.25 to 1.0 and the ratio of the lock heights (rD) varies from 0.25 to 2.5. It is found that the maximum height of the displaced fluid is not affected by the ratios rg and rD. The maximum vertical velocity is detected at the time of collision while intense mixing is detected during collision mainly on the less dense vertically displaced fluid.
Year: 2022