癸酸甲酯、月桂酸甲酯和肉豆蔻酸甲酯的液相声速测量

Measurement of sound speed in methyl caprate,methyl laurate and methyl myristate

癸酸甲酯、月桂酸甲酯和肉豆蔻酸甲酯3种脂肪酸甲酯是生物柴油的主要成分,其声速是喷油系统优化设计和等熵压缩因子计算中所必需的参数之一。针对癸酸甲酯、月桂酸甲脂和肉豆蔻酸甲脂3种物质声速实验数据缺乏的现状,利用布里渊光散射法,沿0.1、2.5、5.5和8.5 MPa 4条等压线,在288.15~498.15 K温度范围内,分别测量了癸酸甲酯、月桂酸甲酯和肉豆蔻酸甲酯的液相声速;分析了声速随温度、压力的变化规律;依据实验数据,给出了在本文p-T热力学区域内,3种物质液相声速与温度和压力的关联式;关联式计算值与实验数据的相对偏差绝对平均值分别为:0.17%(癸酸甲酯)、0.10%(月桂酸甲酯)和0.15%(肉豆蔻酸甲酯),满足工程应用需求。

Methyl caprate,methyl laurate and methyl myristate were considered as the main components of biodiesel.The sound speed in fatty acid methyl esters（FAMEs） is one of the necessary parameter for optimizing the injection process and calculating the isoentropic compressibility.Nevertheless,the sound speed in methyl caprate,methyl laurate and methyl myristate are scarce in the literature.The sound speeds in the three FAMEs were measured by employing Brillouin light scattering method.The measurements were carried out at temperature ranging from 288.15 to 498.15 K along 4 isobaric lines 0.1,2.5,5.5 and 8.5 MPa.The change regularities of sound speed in methyl caprate,methyl laurate and methyl myristate with temperatures and pressures were analyzed,respectively.A rational function as function of pressure and temperature was used to correlate the experimental sound speed in the measured p-T region.Comparing the experimental sound speed with the correlation results,the absolute average deviations（AADs） are 0.17% for methyl caprate,0.10% for methyl caprate and 0.15% for methyl myristate.