Vapor and Liquid (p- ρ- T- x) Measurements of Binary Refrigerant Blends Containing R-32, R-152a, R-227ea, R-1234yf, and R-1234ze(E)

Abstract

The pressure-density-temperature-composition ( $p-\rho -T-x$ ) data of binary refrigerant mixtures containing R-32 (difluoromethane), R-152a (1,1-difluoroethane), R-227ea (1,1,1,2,3,3,3-heptafluoropropane), R-1234yf (2,3,3,3-tetrafluoropropene), and R-1234ze(E) (trans-1,3,3,3-tetrafluoropropene) were measured in both the vapor and liquid phases using a two-sinker, magnetic-suspension densimeter. The specific samples in this study comprised two compositions of approximately (0.3/0.7) and (0.7/0.3) mole fraction for each of the following four binary refrigerant blends: R-32 + R-1234yf, R-32 + R-1234ze(E), R-1234yf + R-152a, and R-1234ze(E) + R-227ea. Single-phase vapor densities were measured over a temperature range of approximately (253 to 293) K and pressures from (0.05 to 0.98) MPa. Single-phase liquid and supercritical densities were measured over a temperature range of approximately (230 to 400) K and pressures up to 22 MPa; for refrigerant blends containing R-1234yf the maximum pressure was limited to 14 MPa. Overall relative combined, expanded (k = 2) uncertainties in density ranged from 0.025% to 0.191%, with an average uncertainty of approximately 0.05%. Here, we present measurement results, along with comparisons to available literature data and to default equations of state and mixture models included in REFPROP.

Keywords: Density; hydrofluorocarbons; hydrofluoroolefins; refrigerant blends.

Figure 1.

Molecular representations of refrigerants used in the binary mixtures studied in this work: R-32, R-152a, R-227ea, R-1234yf, and R-1234ze(E). Carbon atoms are black, hydrogen atoms are grey, and fluorine atoms are blue. Diagrams were constructed using Avogadro.

Figure 2.

Measured ($p$, $\rho$, $T$, $x$) state points for blends containing R-1234yf plotted as density vs temperature. On top are data for two compositions of R-32 + R-1234yf with $x_1=0.33681$ mole fraction shown in (a) and $x_1=0.67205$ mole fraction shown in (b). On bottom are data for two compositions of R-1234yf + R-152a with $x_1=0.33342$ mole fraction shown in (c) and $x_1=0.66526$ mole fraction shown in (d). For all graphs: ◯, measured points; —, phase boundary; ✳, critical point. The phase boundaries and critical points were calculated using the default mixture models included in REFPROP (Version 10.0).

Figure 3.

Measured ($p$, $\rho$, $T$, $x$) state points for blends containing R-1234ze(E) plotted as density vs temperature. On top are data for two compositions of R-32 + R-1234ze(E) with $x_1=0.33512$ mole fraction shown in (a) and $x_1=0.66665$ mole fraction shown in (b). On bottom are data for two compositions of R-1234ze(E) + R-227ea with $x_1=0.33265$ mole fraction shown in (c) and $x_1=0.66803$ mole fraction shown in (d). For all graphs: ◯, measured points; —, phase boundary; ✳, critical point. The phase boundaries and critical points were calculated using the default mixture models included in REFPROP (Version 10.0).

Figure 4.

Relative deviations of the experimental ($p$, $\rho$, $T$, $x$) data for R-32 + R-1234yf from values calculated with REFPROP plotted as a function of (a) temperature, (b) pressure, and (c) density. For all graphs, ◯ represent data for the $x_1=0.33681$ mole fraction blend, while ◻ represent data for the $x_1=0.67205$ mole fraction blend. Additionally, black symbols represent vapor-phase data, red symbols represent liquid-phase data, and blue symbols represent data above the critical temperature ($T_c$) with $T_c=359.842$ K for the $x_1=0.33681$ mole fraction blend and $T_c=352.635$ K for the $x_1=0.67205$ mole fraction blend. Dashed lines are smoothed representations of the overall combined, expanded uncertainty for this binary mixture. Insets show vapor-phase data in greater detail.

Figure 5.

Relative deviations of the experimental ($p$, $\rho$, $T$, $x$) data for R-32 + R-1234ze(E) from values calculated with REFPROP plotted as a function of (a) temperature, (b) pressure, and (c) density. For all graphs, ◯ represent data for the $x_1=0.33512$ mole fraction blend, while ◻ represent data for the $x_1=0.66665$ mole fraction blend. Additionally, black symbols represent vapor-phase data, red symbols represent liquid-phase data, and blue symbols represent data above the critical temperature ($T_c$) with $T_c=377.566$ K for the $x_1=0.33512$ mole fraction blend and $T_c=366.416$ K for the $x_1=0.66665$ mole fraction blend. Dashed lines are smoothed representations of the overall combined, expanded uncertainty for this binary mixture. Insets show vapor-phase data in greater detail.

Figure 6.

Relative deviations of the experimental ($p$, $\rho$, $T$, $x$) data for R-1234yf + R-152a from values calculated with REFPROP plotted as a function of (a) temperature, (b) pressure, and (c) density. For all graphs, ◯ represent data for the $x_1=0.33342$ mole fraction blend, while ◻ represent data for the $x_1=0.66526$ mole fraction blend. Additionally, black symbols represent vapor-phase data, red symbols represent liquid-phase data, and blue symbols represent data above the critical temperature ($T_c$) with $T_c=376.864$ K for the $x_1=0.33342$ mole fraction blend and $T_c=371.043$ K for the $x_1=0.66526$ mole fraction blend. Dashed lines are smoothed representations of the overall combined, expanded uncertainty for this binary mixture. Insets show vapor-phase data in greater detail.

Figure 7.

Relative deviations of the experimental ($p$, $\rho$, $T$, $x$) data for R-1234ze(E) + R-227ea from values calculated with REFPROP plotted as a function of (a) temperature, (b) pressure, and (c) density. For all graphs, ◯ represent data for the $x_1=0.33265$ mole fraction blend, while ◻ represent data for the $x_1=0.66803$ mole fraction blend. Additionally, black symbols represent vapor-phase data, red symbols represent liquid-phase data, and blue symbols represent data above the critical temperature ($T_c$) with $T_c=377.260$ K for the $x_1=0.33265$ mole fraction blend and $T_c=379.890$ K for the $x_1=0.66803$ mole fraction blend. Dashed lines are smoothed representations of the overall combined, expanded uncertainty for this binary mixture. Insets show vapor-phase data in greater detail.

Figure 8.

Relative deviations of experimental density data from values calculated with REFPROP plotted as a function of temperature for (a) R-32 + R-1234yf, (b) R-32 + R-1234ze(E), and (c) R-1234yf + R-152a. For R-32 + R-1234yf: ◯, this work ($x_1=0.33681$ mole fraction); ◻, this work ($x_1=0.67205$ mole fraction); Δ, Cai et al.; ⋈, Dang et al.; ∇, Jia et al.; ✳, Kobayashi et al.; ⧖, Tomassetti et al.; and +, Yang et al.. For R-32 + R-1234ze(E): ◯, this work ($x_1=0.33512$ mole fraction); ◻, this work ($x_1=0.66665$ mole fraction); Δ, Jia et al.; ∇, Kobayashi et al.; ⋈, Tanaka et al.; ✳, Tomassetti et al.; and +, Yamaya et al.. For R-1234yf + R-152a: ◯, this work ($x_1=0.33342$ mole fraction); ◻, this work ($x_1=0.66526$ mole fraction); and Δ, Tomassetti. Additionally, the light orange shaded region shown designates the range of corresponding critical temperatures. Where needed, the graph region covering the majority of data points has been expanded and is shown in the inset for clarity.

Figure 9.

Relative deviations of experimental density data from values calculated with REFPROP plotted as a function of composition for (a) R-32 + R-1234yf, (b) R-32 + R-1234ze(E), and (c) R-1234yf + R-152a. For R-32 + R-1234yf: ◯, this work ($x_1=0.33681$ mole fraction); ◻, this work ($x_1=0.67205$ mole fraction); Δ, Cai et al.; ⋈, Dang et al.; ∇, Jia et al.; ✳, Kobayashi et al.; ⧖, Tomassetti et al.; and +, Yang et al.. For R-32 + R-1234ze(E): ◯, this work ($x_1=0.33512$ mole fraction); ◻, this work ($x_1=0.66665$ mole fraction); Δ, Jia et al.; ∇, Kobayashi et al.; ⋈, Tanaka et al.; ✳, Tomassetti et al.; and +, Yamaya et al.. For R-1234yf + R-152a: ◯, this work ($x_1=0.33342$ mole fraction); ◻, this work ($x_1=0.66526$ mole fraction); and Δ, Tomassetti. Where needed, the graph region covering the majority of data points has been expanded and is shown in the inset for clarity.