Spectral radiative heat transfer in coal furnaces using a hybrid technique

Abstract

A hybrid technique has been developed to solve three-dimensional spectral radiation transport equations for absorbing, emitting and anisotropically scattering media. An optimal mix of computational speed and accuracy is obtained OlS'fl_ilTIONOFTHISDOCUP4EP/T I$ UNLIIfIITI_ orr=,o_uc, the_

Impacts of Organic Structures and Inherent Minerals of Coal on Soot Formation during Pyrolysis

“…Under electron microscopy, soot is generally chain-shaped and is aggregated by nearly spherical basic soot particles with a diameter of about 20-50 nm [2]. The radiation heat transfer capacity of soot is very strong, which can enhance heat transfer and greatly change the temperature distribution around coal particles [3]. Due to the small particle size, incompletely oxidized soot particles will be discharged with the exhaust gas and become one of the main sources of PM 2.5 in the atmosphere [4,5].…”

FURN3D: A computer code for radiative heat transfer in pulverized coal furnaces

“…The selection proc_ss considers method applicability, accuracy and computational efficiency. The basis of the method is discussed elsewhere [Ahluwalia and lm, 1992].…”

“…A technical report [lm and Ahluwalia, 1990] has been prepared on the radiation properties of coal flames, lt assesses the existing experimental data and the theoretical bases for determining the absorption and scattering coefflcients of products of coal combustion, lt describes the results from a parametric study conducted to elucidate the role of char, soot and ash particulates in determining the radiation properties of coal flames. A technical paper [Park, Ahluwalia and lm, 1992] has been prepared on the numerical techniques for solving the radiation transport equation in three-dimensional absorbing, emitting and scattering media.…”

“…1-2 lt evaluates $4, MDA and PI approximation in terms of the computer memory requirement, CPU time and numerical accuracy. A technical report [Ahluwalia and lm, 1992] is being prepared to present results of a sensitivity study on furnace heat absorption for coals of different ash compositions, ash content (coal cleaning), grind (micronization), and moisture levels (slurries).…”

Thermal radiation in oxy-fuel flames

“…The small size in combination with large numbers makes soot particles important contributors to thermal radiation (Ahluwalia and Im, 1994;Fletcher et al, 1997). There are several papers dealing with the formation of soot in gas-fired flames and how soot formation is affected by for example gaseous additives.…”