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 propagati...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.展开更多
To select drought-resistant and dust-tolerant native species suitable for use in the rehabilitation of major coal bases in northwest China,nine tree species were identified for growth rates,biomass,harm index,and phys...To select drought-resistant and dust-tolerant native species suitable for use in the rehabilitation of major coal bases in northwest China,nine tree species were identified for growth rates,biomass,harm index,and physiological indices under drought and high dust stress conditions.The results showed that,in the dust resistance index system,the order was Caragana korshinskii>Amorpha fruticosa>Sabina vulgaris>Hedysarum scoparium>Tamarix chinensis>Ammopiptanthus mongolicus>Ulmus pumila>C aryopteris mongholica>Elaeagnus angustifolia.In a comprehensive drought and dust resistance index system,14 indices(such as shoot length,stomatal conductance,and peroxidase)had the larger weight indices.The drought and dust resistance order of the tree species was C aragana korshinskii>Ulmus pumila>Amorpha fruticosa>Sabina vulgaris>Caryopteris mongholica>Ammopiptanthus mongolicus>H edysarum scoparium>Tamarix chinensis>Elaeagnus angustifolia.This study provides effective strategies and references for selecting suitable tree species for arid mining sites in China,and also for the revegetation of coal mining sites worldwide.展开更多
文摘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.
基金supported by National Key Research and Development Program of China“Eco-security technology for coal mining bases in the northwestern arid desert regions in China”(2017YFC0504400)its project“Study on vegetation rehabilitation and conservation in abandoned coal mining land”(2017YFC0504402)。
文摘To select drought-resistant and dust-tolerant native species suitable for use in the rehabilitation of major coal bases in northwest China,nine tree species were identified for growth rates,biomass,harm index,and physiological indices under drought and high dust stress conditions.The results showed that,in the dust resistance index system,the order was Caragana korshinskii>Amorpha fruticosa>Sabina vulgaris>Hedysarum scoparium>Tamarix chinensis>Ammopiptanthus mongolicus>Ulmus pumila>C aryopteris mongholica>Elaeagnus angustifolia.In a comprehensive drought and dust resistance index system,14 indices(such as shoot length,stomatal conductance,and peroxidase)had the larger weight indices.The drought and dust resistance order of the tree species was C aragana korshinskii>Ulmus pumila>Amorpha fruticosa>Sabina vulgaris>Caryopteris mongholica>Ammopiptanthus mongolicus>H edysarum scoparium>Tamarix chinensis>Elaeagnus angustifolia.This study provides effective strategies and references for selecting suitable tree species for arid mining sites in China,and also for the revegetation of coal mining sites worldwide.
