Eventos Anais de eventos
COBEM 2017
24th ABCM International Congress of Mechanical Engineering
An investigation about the use of a constant absorption cross-section for radiative heat transfer computations in nonuniform CO2 gases.
Submission Author:
Gabriel de Lima Bernardino , RN
Co-Authors:
Andre Maurente, Gabriel de Lima Bernardino
Presenter: Gabriel de Lima Bernardino
doi://10.26678/ABCM.COBEM2017.COB17-1448
Abstract
Processes of heat transfer by radiation are very important in scientific and industrial applications. When these processes involve participating gases at high temperatures that emit and absorb radiation, radiant exchanges can become the main mechanism of heat transfer. The computation of the spectral absorption cross-section of CO2 (which is essential to compute emission and absorption of radiation), requires a discretization of the spectrum in several spectral points. This work presents an analysis of the relation of CO2 concentration with the absorption cross-section. Based on the HITEMP2010 database, the spectral absorption cross-section was calculated considering a uniform media with temperatures of 500 K, 1500 K and 2500 K and four different molar fractions of CO2. An analysis was also accomplished for a non-isothermal medium. The results show that as the absorption cross-section is much less sensible to chemical species concentration than the absorption coefficient, a constant absorption cross section can be used in nonuniform gases composed of CO2 and inert species with acceptable accuracy.
Keywords
Absorption cross-section, Radiation heat transfer, Spectral properties, HITEMP
