超临界二氧化碳物性参数测量方法综述

Review of measurement methods for physical parameters of supercritical carbon dioxide

对于超临界二氧化碳(S-CO_(2))物性参数的获取,一般可从美国国家标准与技术研究院(NIST)直接查询,但SCO_(2)在临界点处物性发生剧烈变化。在实际工业应用中,S-CO_(2)的密度、粘度和热导率这3个方面对与超临界二氧化碳布雷顿循环的研究有着很重要的作用,为了解目前S-CO_(2)物性的测量方法,该文对当前所涉及到的S-CO_(2)基本物性测量方法进行梳理,包括密度测量法中的可变体积法、单双沉浮法、振动管法;导热率测量法中的平板法、双圆筒和热线法;粘度测量中的落球法、粒子沉降法、旋转体法、振动盘法、振动线法。在对物性测量方法的整理后,提出可使用振动梁法测量S-CO_(2)的密度,振动线法测量S-CO_(2)的粘度,平板法测量S-CO_(2)的热导率。

The physical properties of supercritical carbon dioxide(S-CO_(2))change drastically at the critical point.The acquisition of physical properties of S-CO_(2)can generally be directly inquired from the National Institute of Standards and Technology.In practical industrial applications,the three aspects of S-CO_(2)density,viscosity and thermal conductivity play an important role in the research of supercritical carbon dioxide Brayton cycle.In order to understand the current measurement methods of S-CO_(2)physical properties,this article presents the basic physical properties measurement methods of S-CO_(2)involved,introducing variable volume method,single/double sinking densitometer and vibrating tube method to measure density;falling ball method,particle-velocity method,rotating cylinder body method,oscillating-disk viscometer and vibratingwire viscometer;parallel plate method,concentric cylinder and hot wire transient method to measure thermal conductivity.After finishing the physical property measurement methods,it was found that the vibrating cantilevers method can be used to measure the density of S-CO_(2),the vibrating-wire method can be used to measure the viscosity of S-CO_(2)and the parallel plate method to measure the thermal conductivity of S-CO_(2).