Speed of sound measurement and prediction of ethyl hexanoate and ethyl octanoate at temperatures from (293.15 to 473.15) K and pressures from (0.1 to 10) MPa

Abstract Fatty acid ethyl esters (FAEEs) are the main components in some biodiesels, which are important alternatives of fossil fuels. In this paper, we carry out the measurements of the speed of sound in two FAEEs at the temperatures from (293.15 to 473.15) K and at the pressures up to 10 MPa, including saturated liquid and compressed liquid. The relative expanded uncertainty in the speed of sound is estimated to be less than 1.0% with coverage factor of k to be 2. The data in saturated liquid and compressed liquid are fitted into polynomials. For saturated liquid, the D AAD is 0.16% for ethyl hexanoate and 0.09% for ethyl octanoate. For compressed liquid, the D AAD is 0.31% for ethyl hexanoate and 0.16% for ethyl octanoate. The data were also used to assess the predictive ability of Wada’s model.