三种脂肪酸甲酯音速测量与相关热物理性质推算

摘要

脂肪酸甲酯(FAMEs)是生物燃料的重要成分，为了获取它们的热物理性质数据，利用布里渊散射法测量了3种脂肪酸甲酯常压下的音速，测量温度范围为293.15～423.15 K(己酸甲酯)、293.15～443.15 K(庚酸甲酯)、463.15 K(辛酸甲酯)。为方便工程应用，将文献数据和本文实验数据拟合成温度的关联式，实验值与关联式计算值的相对偏差绝对平均值为：0.29%(己酸甲酯)、0.24%(庚酸甲酯)、0.27%(辛酸甲酯)。应用音速实验数据，分别结合Wada模型和Auerbach模型估算3种脂肪酸甲酯的密度和表面张力。结果表明，Wada模型可以很好地用来估算密度，而Auerbach模型对表面张力的估算结果与文献值偏差较大。%Fatty acid methyl esters (FAMEs) are the main components of biodiesels. In order to obtain their thermophysical properties data, the sound speeds of three FAMEs were measured using Brillouin light scattering method (BLS) at the temperature from 293.15 to 463.15 K and pressure of 0.1 MPa. The correlations for the sound speed of FAMEs in literature and this paper were also fitted as the function of temperature to satisfy the usage in engineering areas. The AADs were 0.29% for methyl caproate, 0.24% for methyl heptanoate and 0.27% for methyl caprylate, respectively. And the experimental data were also used to predict the density and the surface tension by Wada’s model and Auerbach’s model, respectively. It showed that the predictive ability of Wada’s model for the density was good, while Auerbach’s model did not perform well in the prediction of the surface tension.