67th Annual Meeting of the APS Division of Fluid Dynamics (November 23, 2014 — November 25, 2014)
V0022: Salt fingers in double diffusive convection bounded by two parallel plates
Authors
Yantao Yang, Physics of Fluids Group, Faculty of Science and Technology, MESA+ Research Institute, and J. M. Burgers Centre for Fluid Dynamics, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
Erwin P. van der Poel, Physics of Fluids Group, Faculty of Science and Technology, MESA+ Research Institute, and J. M. Burgers Centre for Fluid Dynamics, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
Rodolfo Ostilla-Monico, Physics of Fluids Group, Faculty of Science and Technology, MESA+ Research Institute, and J. M. Burgers Centre for Fluid Dynamics, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
Chao Sun, Physics of Fluids Group, Faculty of Science and Technology, MESA+ Research Institute, and J. M. Burgers Centre for Fluid Dynamics, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
Roberto Verzicco, Dipartimento di Ingegneria Industriale, University of Rome “Tor Vergata”, Via del Politecnico 1, Roma 00133, Italy
Detlef Lohse, Physics of Fluids Group, Faculty of Science and Technology, MESA+ Research Institute, and J. M. Burgers Centre for Fluid Dynamics, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
In ocean, the fluid density depends mainly on temperature and salinity. Temperature diffuses much faster than salinity. This causes convection even when the overall stratification is stable, saying light fluid stays on top of heavy fluid. When the condition is favorable, vertically elongated thin structures develop. Such structures are called salt fingers and commonly discovered in ocean. Here we visualise the salt finger structures between two parallel plates, where the top plate is warmer and saltier than the bottom one. We set the diffusivities, which measured by Prandtl numbers, similar to those for seawater. Fresh and salty fingers grow from bottom and top plates, respectively. They extend to the opposite plate and keep their horizontal locations for an extremely long time.