Modeling the surface tension of refrigerant mixtures with linear gradient theory

Using a New Proposed Influence Parameter of Gradient Theory for CH4/n-alkane Binary Systems: What Advances Can Be Achieved?

“…(21); therefore, the new proposed influence is more accurate than the one in Eq. (20) suggested in previous investigations [11][12][13][14][15][16]. For C 1 /nC 6 binary system, the performance of these two influence parameters is approximately the same.…”

“…In previous investigations [11][12][13][14][15][16], the following form of influence parameter was used as a function of liquid and vapor densities.…”

“…In recent years, three groups of empirical expressions have been used to determine the influence parameter of the gradient theory: (1) constant influence parameter [6][7][8]; (2) temperature dependent influence parameter [9,10]; (3) the influence parameter based on the densities of the vapor and liquid phases [11][12][13][14][15][16]. The first group makes the theory easer.…”

“…On the other hand, it was concluded that the second group lead to a significant improvement, but it has some limitations, for example, the temperature dependent influence parameter used by Zuo and [9,17,18] is not possible to be applied under supercritical conditions so that the reduced temperature should be set to a single value. In recent years, the third group of influence parameter of the gradient theory [11][12][13][14][15][16] has been successfully applied to refrigerant mixtures and water/gas systems. The third group of influence parameter has shown the potential to overcome the limitations of the first and second groups.…”

“…Furthermore, a new correlation based on the densities of the vapor and liquid phases have been proposed. The performance of new suggested influence parameter has been also compared with the previous proposed influence parameter in [11][12][13][14][15][16]. Furthermore, the performance of suggested influence parameter has been discussed.…”