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Compressed liquid density and speed of sound measurements and correlation of the binary mixture Carbon dioxide (CO2) + 1,1-difluoroethene (R1132a)} at temperatures from 220 K to 350 K
Published
Author(s)
Davide Menegazzo, Aaron Rowane, Laura Fedele, Sergio Bobbo, Giulia Lombardo, Mark O. McLinden
Abstract
The blend of carbon dioxide and R1132a has been suggested as feasible alternative to R23 in low-temperature devices. In this work, we present a new set of experimental data for compressed-liquid density, vapour density and compressed-liquid speed of sound for the binary system CO2 + R1132a by means of a two-sinker densimeter and a pulse-echo-type instrument, respectively. The measurements have been performed over the temperature range of 220 K to 350 K with pressures to 30 MPa for density; the speed of sound measurements cover the range 230 K to 350 K with pressures to 55 MPa; for both properties two mixture compositions were measured. Finally, we present an Equation of State (EoS) correlation for the experimental data based on a Helmholtz free energy model, which shows a good agreement with the measurements. The mixture strongly absorbed the sound pulse, and the usual dual-path analysis was not possible. Thus, we developed a method using only the short-path signal.
Menegazzo, D.
, Rowane, A.
, Fedele, L.
, Bobbo, S.
, Lombardo, G.
and McLinden, M.
(2023),
Compressed liquid density and speed of sound measurements and correlation of the binary mixture {Carbon dioxide (CO2) + 1,1-difluoroethene (R1132a)} at temperatures from 220 K to 350 K, 26th International Congress of Refrigeration, Paris, FR, [online], https://doi.org/10.18462/iir.icr.2023.0173, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=936175
(Accessed October 2, 2025)