CFD code is used to obtain velocity and temperature distributions inside the tank. Three dimensional unsteady solutions are taken by using implicit method in segregated solver. The discretization is achieved by using standard method for pressure and by using first upwind method for momentum, energy, turbulent kinetic energy and turbulent dissipation rate equations. The SIMPLE (semi-implicit method for pressure-linked equations) algorithm was used for flow calculations [10].

Te under-relaxation factors are assumed as 0.3, 0.7, 1, 0.8, 0.8 and 1 for pressure, momentum, energy equations, turbulent kinetic energy (k), turbulent dissipation rate (s) and turbulent viscosity (pt) as, respectively. This factor has assumed as 1 for body force and density.

The convergence factors are used as 10-3 for continuity, momentum, turbulent kinetic energy and turbulent dissipation rate equations. This value is taken 10-6 for energy equations [10].