عنوان مقاله [English]
In this paper, the conditions of convergence and thermodynamic consistency of the Kupershtokh model for simulating a 2D droplet are investigated. Hence, the coexistence curve of liquid and vapor phases is divided into four levels according to the constant of potential function, k and the weight coefficient of the inter-molecular forces, A. Accordingly, a range is reported for k at each level. This range for level 1 with the lowest density ratio is kmin= 0.05 to kmax = 0.22 and for the fourth level with the highest density ratio is kmin=0.002 to kmax = 0.01. Also, the appropriate weight coefficient for inter-molecular forces, Afit is obtained for yielding the thermodynamic consistency at levels 1 to 4 equal with 0.25, 0.025, -0.082 and -0.125, respectively. The effect of weight coefficient on the amount and direction of interface forces is also investigated. Results show that the choice of A=0.5 produces symmetric and A=0 causes asymmetric forces in the interface. In other words, the combination of two symmetrical and non-symmetric forces provides conditions for reducing the parasitic velocities and increasing the stability conditions. Finally, the problem of mass conservation in four levels of density ratio is investigated. Results show that Kupeshtokh model has a better behavior in controlling the mass of the droplet in the high density ratios. So, the change in the mass of the droplet at level 1 is more than 20% and at the level of 4 is less than 1%.