Micro-organic dust combustion considering particles thermal resistance
来源期刊：中南大学学报(英文版)2015年第7期
论文作者：Mohammadamin Soltaninejad Farzad Faraji Dizaji Hossein Beidaghy Dizaji Mehdi Bidabadi
文章页码：2833 - 2840
Key words：micro-organic dust; biot number; particles thermal resistance; flame temperature; burning velocity
Abstract: Organic dust flames deal with a field of science in which many complicated phenomena like pyrolysis or devolatization of solid particles and combustion of volatile particles take place. One-dimensional flame propagation in cloud of fuel mixture is analyzed in which flame structure is divided into three zones. The first zone is preheat zone in which rate of the chemical reaction is small and transfer phenomena play significant role in temperature and mass distributions. In this model, it is assumed that particles pyrolyze first to yield a gaseous fuel mixture. The second zone is reaction zone where convection and vaporization rates of the particles are small. The third zone is convection zone where diffusive terms are negligible in comparison of other terms. non-zero Biot number is used in order to study effect of particles thermal resistance on flame characteristics. Also, effect of particle size on combustion of micro organic dust is investigated. According to obtained results, it is understood that both flame temperature and burning velocity decrease with rise in the Biot number and particle size.
Mohammadamin Soltaninejad1, Farzad Faraji Dizaji2, Hossein Beidaghy Dizaji3, Mehdi Bidabadi1
(1. School of Mechanical Engineering Department of Energy Conversion, Combustion Research Laboratory,
Iran university of Science and Technology, Narmak, Tehran 16887, Iran;
2. School of Engineering, The University of Vermont, 33 Colchester Avenue, Burlington, Vermont 05405, USA;
3. Young Researchers and Elite Club, Tabriz Branch, Islamic Azad University, Tabriz, Iran)
Abstract:Organic dust flames deal with a field of science in which many complicated phenomena like pyrolysis or devolatization of solid particles and combustion of volatile particles take place. One-dimensional flame propagation in cloud of fuel mixture is analyzed in which flame structure is divided into three zones. The first zone is preheat zone in which rate of the chemical reaction is small and transfer phenomena play significant role in temperature and mass distributions. In this model, it is assumed that particles pyrolyze first to yield a gaseous fuel mixture. The second zone is reaction zone where convection and vaporization rates of the particles are small. The third zone is convection zone where diffusive terms are negligible in comparison of other terms. non-zero Biot number is used in order to study effect of particles thermal resistance on flame characteristics. Also, effect of particle size on combustion of micro organic dust is investigated. According to obtained results, it is understood that both flame temperature and burning velocity decrease with rise in the Biot number and particle size.
Key words:micro-organic dust; biot number; particles thermal resistance; flame temperature; burning velocity
