中文摘要：

目前有关烃类流体相态的研究已较为成熟，能为油气田的高效开发提供相应的理论指导和技术支持。但研究成果大多忽略多孔介质对流体相态的影响。为此，在充分考虑流体与多孔介质相互作用的基础上，开展多孔介质内流体相态特征的研究十分必要。随着研究的不断深入，超声波探测技术不受压力温度限制、不改变流体成分、检测成本低、对人体无害等优点逐渐得到重视，并在多孔介质内相态研究领域逐渐得到了应用。在参考国内外相关文献资料的基础上，简述了超声波的探测机理，重点综述了超声波探测在多孔介质内天然气水合物、凝析油气相态特征研究的应用进展，并指出了目前存在的主要问题及今后的研究重点。

英文摘要：

So far, the study of the phase behavior of hydrocarbon fluids has been relatively mature. It could supply correspond- ing theoretical guidance and technical support for the efficient development of the oil and gas reservoirs. However, the effect of porous media on phase behavior mostly is ignored. Therefore, it is crucial to study the phase behavior of fluids in porous media with due consideration of the interactions of the fluids and porous media. With the further development in this field, advantages of the ultrasonic detection such as no limit of pressure and temperature, no effect on fluid compositions, low cost and no harm to human beings have received increasingly attention and the technique is gradually being used in phase behavior of fluids in porous media. In this paper, with reference to abundant literature at home and abroad, detection mechanism of the ultrasonic wave is described briefly and research advances of the ultrasonic detection in phase behavior of gas hydrates and condensate gas system is summarized emphatically. And, the existing problems and future research of this technique are also identified.