A presentation method of the thermophysical properties of matter in the form of spreadsheets

Abstract

Abstract The research of methods to reduce CO2 emissions into the atmosphere has led to formation of new thermodynamic cycles in which oxygen is separated from the air before combustion. Fuel, pure oxygen and some recirculating substances, from which it is easy to separate CO2 formed during the combustion, are fed into the combustion chamber. Usually, CO2, H2O or a mixture of thereof are used in the form of recirculated flue gas. The parameters in such cycles are chosen at different points in the cycle, where the working fluid can be in liquid, gaseous or supercritical states. The computational study of such cycles requires a convenient presentation of the thermophysical properties of different substances that can be part of the working fluid in a wide range of parameters. The aim of this work is to develop a data array and a computational module (spreadsheet) considering the dependence of the basic thermophysical properties of various substances. A conversion method of variables that allowed the formation of a compact interpolation grid with minimal loss of accuracy during subsequent interpolation was proposed, where the use of integers for the nodal values of the independent variables saved computational resources during interpolation significantly.