Measurement of the Speed of Sound in Methyl Caprylate from 298.22 to 608.38 K and up to 10 MPa

Methyl caprylate is expected to be one of the main components of biodiesel due to its high cetane number and good oxidation stability. Details of the experimental speeds of sound in methyl caprylate are very scarce, especially in high-temperature regions. Therefore, the speed of sound in liquid methyl caprylate was measured by the Brillouin light scattering method in the temperature range of 298.22-608.38 K and at pressures of up to 10 MPa. The relative expanded uncertainty of the speed of sound is estimated to be less than 1.32% (coverage factor k = 2). The variation of the speed of sound with the temperature and pressure was analyzed. Besides, the correlation for the speed of sound as a function of temperature and pressure is presented based on the experimental data. The absolute average of relative deviation between the experimental data and the calculated results is 0.29%.