A measurement procedure using a modified two-chamber pulse-echo experimental setup is presented, enabling acoustic absorption and bulk viscosity (volume viscosity) measurements in liquids up to high temperature and pressure. Acoustic absorption measurements are particularly challenging, since other dissipative effects, such as diffraction at the acoustic source and at acoustic reflectors, are typically superimposed to the measurement effect. Acoustic field simulations are performed, allowing to investigate acoustic wave propagation qualitatively. The absorption coefficient is determined by evaluating the signal spectrum’s raw moments and applying a method to identify and correct systematic measurement deviations. Measurement uncertainties are estimated by a Monte Carlo method. In order to validate the present measurement procedure, the acoustic absorption in liquid methanol, n-hexane, n-octane, and n-decane is determined experimentally and compared to literature data. The measurement results for methanol are additionally validated by comparison to bulk viscosity data sampled with molecular dynamics simulation.

介绍了使用改进的两室脉冲回波实验装置的测量程序，可以在高达高温和高压的液体中进行声吸收和体积粘度（体积粘度）测量。声吸收测量尤其具有挑战性，因为其他耗散效应，例如声源和声反射器处的衍射，通常会叠加到测量效应上。执行声场模拟，允许定性地研究声波传播。吸收系数是通过评估信号频谱的原始矩并应用一种方法来识别和纠正系统测量偏差来确定的。测量不确定度是通过蒙特卡罗方法估计的。为了验证当前的测量程序，液体甲醇、正己烷、正辛烷和正癸烷中的声吸收是通过实验确定的，并与文献数据进行比较。通过与使用分子动力学模拟采样的体积粘度数据进行比较，进一步验证了甲醇的测量结果。