Simultaneous optimization of saturation equations for two hydrocarbons and four hydrofluoroolefins refrigerants

Abstract

Abstract This research exhibits a different simultaneous optimization for saturation equations of six pure refrigerants from Hydrocarbon (HCs) and Hydrofluoroolefins (HFOs). The study objective is to model two different group of saturation equations in accordance with the same structural forms, one for n-butane (R600) and isobutane (R600a), and other for 2,3,3,3-tetrafluoropropan (R1234yf), trans-1,3,3,3-tetrafuoropropene (R1234ze(E)), cis-1,3,3,3-tetrafuoropropene (R1234ze(Z)), and trans-1-chloro-3,3,3-trifluoropropene (R1233zd(E)) refrigerants. Genetic algorithm with weighted least square regression was assigned to carry out the research objectives. The modeling equations for both groups are valid from triple points up to temperature nearby the critical points. The uncertainties respecting to each equation of R600, R600a, R1234yf, R1234ze(E), R1234ze(Z), and R1233zd(E) refrigerants are estimated to be 0.05%, 0.75%, 0.10%, 0.35%, 0.57%, and 0.22% in saturated liquid density; 0.30%, 2.68%, 0.86%, 1.48%, 4.13%, and 1.23% in saturated vapor density; and 0.73%, 2.15%, 0.08%, 0.47%, 0.97%, and 2.85% in vapor-pressures, respectively. The new ancillary equations can be used to calculate the saturation properties for engineering interests.