运用液体声学理论研究超临界二氧化碳的声特性

利用液体声学模型，根据美国国家标准局提供的二氧化碳声速、密度、摩尔体积和绝热压缩系数数据，计算了气态、液态和超临界态二氧化碳在不同温度和压力条件下的摩尔声速、摩尔压缩系数及Van der Waals 常数. 分析发现，在较宽的温度和压力范围内，液体中的声学模型能够很好地运用于超临界态二氧化碳的研究. 并在液体声学模型适用范围内，计算了超临界二氧化碳在不同温度及压力状态下的表面张力、粘度、自扩散系数，为超临界流体技术提供了参考数据，并分析了这些参量的变化规律.关键词：超临界二氧化碳声速摩尔声速摩尔压缩系数

Study of acoustical properties of supercritical carbon dioxide using liquid acoustical theory

Molar sound velocity, molar adiabatic compressibility and Van der Waals constant of gaseons, liquid and supercritical carbon dioxide at different temperature and pressure are calculated using liquid acoustical models and data of sound velocity, density, molar volume and adiabatic compressibility of carbon dioxide provided by National Institute of Standards and Technology, USA. The results show that the liquid acoustical models can be used in study acoustical property of supercritical carbon dioxide in wide ranges of temperature and pressure. The surface tension, conglutination and diffusivity at different temperatures and pressures are calculated. And the mutative rules of these physical quantities are analyzed. The data can provide reference for supercritical liquid technique.