Influence of particle and gas radiation in oxy-fuel combustion
Artikel i vetenskaplig tidskrift, 2013

This work investigates thermal radiation in oxy-fired conditions. Both gas and particle radiation is modelled in an axi-symmetric cross section of a cylindrical furnace and differences in the radiative transfer between air- and oxy-firing are investigated. The particle radiative properties are calculated according to the Mie-theory, accounting for the spectral properties. The scattering by the particles is assumed to be isotropic. For the gas radiation, a Statistical-Narrow-Band (SNB) model is applied as reference. The properties of the combustion gas and the particle load are derived from measurements in a lignite flame in Chalmers University's 100 kW test rig. The wall flux and the radiative source term along the cylinder's diameter are compared to evaluate the difference in radiation between air- and oxy-fuel combustion. Special emphasis is put on the influence of load and distribution of particles, both in the flame and at the furnace exit. The results show that the presence of particles suppresses the influence of gas composition and small differences are seen between the different gas mixtures. It is also concluded that variation of temperature and particle load can have a significant impact on the radiative heat transfer. (C) 2013 Elsevier Ltd. All rights reserved.

fly-ash

systems

h2o

heat-transfer

coal

Heat transfer

Radiation

intensity

narrow-band model

high-temperature

Combustion

co2

soot

Oxy-fuel

Particles

Författare

Robert Johansson

Chalmers, Energi och miljö, Energiteknik

Bo G Leckner

Chalmers, Energi och miljö, Energiteknik

Klas Andersson

Chalmers, Energi och miljö, Energiteknik

Filip Johnsson

Chalmers, Energi och miljö, Energiteknik

International Journal of Heat and Mass Transfer

0017-9310 (ISSN)

Vol. 65 143-152

Ämneskategorier

Fysik

DOI

10.1016/j.ijheatmasstransfer.2013.05.073