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A Dual-Path Pulse-Echo Instrument for Liquid-Phase Speed of Sound and Measurements on p-Xylene and Four Halogenated-Olefin Refrigerants [R1234yf, R1234ze(E), R1233zd(E), and R1336mzz(Z)]
Published
Author(s)
Mark O. McLinden, Richard A. Perkins
Abstract
We describe an instrument to measure the speed of sound in liquids based on the dual-path, pulse-echo technique; it covers a temperature range of 228.15 K to 423.15 K, with pressures up to 93 MPa. It differs from similar instruments in the method of mounting the quartz-crystal transducer, a path-length ratio of 2.5:1, and automated data-collection protocols. The path-length difference was calibrated with measurements on high-purity propane. The performance of the instrument was verified by comparison with recent literature data on p-xylene. We present new liquid-phase measurements for the halogenated-olefin refrigerants 2,3,3,3-tetrafluoroprop-1-ene [R1234yf], trans-1,3,3,3-tetrafluoroprop-1-ene [R1234ze(E)], trans-1-chloro-3,3,3-trifluoroprop-1-ene [R1233zd(E)], and cis-1,1,1,4,4,4-hexafluorobut-2-ene [R1336mzz(Z)]. These measurements cover a combined temperature range of 230 K to 420 K, with pressures up to 50 MPa; these data are compared to literature data (where available) and multi-property equations of state. The average relative expanded uncertainty in speed of sound ranged from 0.035 % to 0.088 % for the different fluids.
McLinden, M.
and Perkins, R.
(2023),
A Dual-Path Pulse-Echo Instrument for Liquid-Phase Speed of Sound and Measurements on p-Xylene and Four Halogenated-Olefin Refrigerants [R1234yf, R1234ze(E), R1233zd(E), and R1336mzz(Z)], Industrial and Engineering Chemistry Research, [online], https://doi.org/10.1021/acs.iecr.3c01720, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=936691
(Accessed October 20, 2025)