**Author details**

temperature difference for realistic values of parameters (*A*=1.25, *Ra* =2.7×10<sup>7</sup>

**Nomenclature**

*A* aspect ratio =*h* / *b b* width of the system m

140 Heat Transfer Studies and Applications

*c* concentration kgm-3

*D* diffusion coefficient m2

*h* height of the system m

*Le* Lewis number = κ/D

*N uave* average Nusselt number

*P* dimensionless pressure Pr Prandtl number =ν/k

*Tcold* temperature on the cold wall K *Thot* temperature on the hot wall K

*U* , *V* , *W* dimensionless velocity

*p* pressure Pa

*T* temperature K

*t* time s

*g* acceleration due to gravity ms-2

*H* dimensionless height of the system

*N* buoyancy ratio =*β*(*c*max −*c*min) /{*α*(*Thot* −*Tcold* )}

*Ra* Rayleigh number = *<sup>g</sup>* <sup>⋅</sup>*α*(*Thot* <sup>−</sup>*Tcold* ) <sup>⋅</sup> *<sup>b</sup>* <sup>3</sup> / (*<sup>κ</sup>* <sup>⋅</sup>*ν*)

*B* dimensionless width of the system

*C* dimensionless concentration =(*c* −*c*min) /(*c*max −*c*min)

s-1

*c*max initial maximum concentration (initial concentration in a linear profile) kgm-3 *c*min initial minimum concentration (initial concentration in a linear profile) kgm-3

Pr=7.15for an NaCl-H2O system). The initial salt concentration linear profile was examined.

Three-dimensional numerical result with a high spatial resolution can capture the fine structures such as salt fingers and traveling plumes. In the linear profile, near the interface, vertical motion is dominant due to salt fingers in each layer. In addition, when the computa‐ tional domain changes, it has a big influence on the behaviour of plume that appears on the diffusive interface. As a result, the mixing state of the entire faction is greatly different.

, *N* =0.882,

#### Hideo Kawahara

Address all correspondence to: kawahara@s.oshima-k.ac.jp

National Institute of technology, Oshima College, Japan

#### **References**

