Experimental study of turbulent mixing in the presence of double-diffusive convection and a brief view of its effect on the melting rate in Antarctica

The study of turbulent mixing in the presence of double-diffusive convection is an important area of research in oceanography. Double diffusive convection (DDC) occurs when two fluids with different diffusion coefficients are brought into contact, leading to complex mixing patterns. The laboratory experiments depict the relation between salt finger convection and intermittent turbulence in the oceanic thermocline. The entrainment of a stably stratified layer into a turbulent mixed layer in a confined region was studied in the laboratory for different Richardson numbers. Here we present the results of some laboratory experiments on the role of double-diffusive convection (DDC) on turbulence entrainment near a density interface. It appears that DDC has little effect on turbulence entrainment when turbulence intensity is large. Through an analysis of density interface variations and depth across density differences (Δρ = ۵, ۱۰, ۱۵, and ۲۰ g/l). The ۲۰ g/l density difference perfectly mirrors real ocean conditions, and it is clear that the time for density interference to diminish in depth is significantly longer than for the lower densities. The Ue/U values convincingly range from ۰.۰۰۰۱ to ۵, while the Richardson number spans from under ۰.۰۰۱ to approximately ۵ for density differences of ۵, ۱۰, and ۱۵ g/l. Notably, for ۲۰ g/l, the measurements are more and more precise, with Ue/U falling between ۰.۱ and ۵, and Ri ranging from ۰.۰۰۱ to ۱.۰. Also, in these experiments, entrainments at a density interface seems not to be effected much by double diffusion.

کلیدواژه ها:

turbulence ، double-diffusive convection ، laboratory experiments ، ocean ، melting rate