图书馆订购 Guest

ISSN Online: 2379-1748

ISBN Flash Drive: 978-1-56700-518-9

5th Thermal and Fluids Engineering Conference (TFEC)
April, 5-8, 2020, New Orleans, LA, USA

FLUID PROPERTY VARIATION ANALYSIS IN A HEAT EXCHANGER USING SUPERCRITICAL FLUIDS

Get access (open in a new tab) pages 391-400
DOI: 10.1615/TFEC2020.hex.032151

摘要

A Supercritical fluid is a fluid held at or above its critical temperature and critical pressure, where distinct liquid and gaseous phases do not exist. Carbon dioxide behaves as a supercritical fluid above its critical temperature (304.25 K) and critical pressure (72.9 atm). The thermophysical properties of CO2 change significantly with temperature and pressure in the supercritical region. At a considered pressure value, the thermal conductivity, dynamic viscosity and density increases with the increase in temperature. This paper aims to investigate the performance of a two-fluid co-current and counter co-current flow heat exchanger, with one of the interacting fluids as supercritical carbon dioxide. The governing equations are written for one dimensional flow of the fluids. For simplicity, only the variation of the isobaric heat capacity of supercritical CO2 with temperature along the heat exchanger length is considered. The equations are solved by finite element method using MATLAB software. The performance of the heat exchanger is analyzed using temperature plots and effectiveness-NTU method. The performance of heat exchanger is found to be enhanced with the use of supercritical fluids when compared with that of a regular fluid (water).