Review of existing and development of a novel mathematical model for supercritical CO₂ cycles working fluid

Institute of Heat Engineering, Warsaw University of Technology, Nowowiejska 21 Street 00-665 Warsaw, Poland

^* Corresponding author: marcin.wolowicz@itc.pw.edu.pl

Abstract

The paper aims to compare the models of working fluids against experimental data for carbon dioxide close to its critical conditions. Fortunately, most of the work is already done and published where the authors compared the models based on the equation of the state (EoS). There are a few other models which were not investigated, thus we would like to add a few new results here and focus only on near-critical properties where the biggest deviation between experimental and calculated properties can be observed. The area of interest was pressure range of 7.39 – 20 MPa and temperature range of 304-340 K just above fluid critical point (7.39 MPa, 304.25 K). Model validation was performed for density and heat capacity as one of the most important parameters in preliminary cycle analysis.