68th Annual Meeting of the APS Division of Fluid Dynamics (November 22, 2015 — November 24, 2015)

V0024: Numerical simulation of 3d gravity current moving down a uniform slope

Authors

• Reuben Chiew, University of Melbourne, Australia
• Nan Yi, University of Melbourne, Australia
• Quan Wen, University of Melbourne, Australia
• Chong Shen Ng, University of Melbourne, Australia
• Shuang Jie Zhu, University of Melbourne, Australia
• Sivaramakrishnan Balachandar, University of Florida, USA
• Nadim Zgheib, University of Florida, USA
• Andrew Seng Hock Ooi, University of Melbourne, Australia

DOI: https://doi.org/10.1103/APS.DFD.2015.GFM.V0024

Gravity currents occur when fluids of different density are brought together. They are relevant in many engineering applications such as the dispersion of hazardous gas cloud, spillage heavy chemicals from marine vehicles and avalanche. Most of the studies on gravity current tend to assume that they travel on a horizontal surface. However, there are many applications where gravity currents travel down a slope. In such a situation, buoyancy effects may become more important which changes the physical dynamics of the gravity currents. The formation and evolution of gravity current under such a condition is not well understood. Theoretical investigations have found that the gravity current will assume a "self-similar" circular wedge shape. This contradicts experimental observation that the gravity current takes on a shape that is more akin to a triangular wedge. In our present simulation, we present data from full three-dimensional direct numerical simulation that agrees with experimental observation. The physical mechanisms leading to formation of this triangular shape and the entrainment properties of such a structure is investigated.