【摘要】 结合多孔介质模型和RNG k-ε紊流模型,建立密集烤烟用洁净型煤反向燃烧热风炉炉内空气流动数值计算模型。应用单因素仿真优化方法,研究炉内空气流动分布和空气利用率随煤床高度、静压区侧壁清灰口高度及上下层型煤蜂窝孔对准程度的变化规律,归纳其操作特性。研究表明:空气利用率是空气速度的3次函数,煤床高度的3次函数,清灰口高度的2次函数和多孔介质区内部阻力系数的2次函数;反烧炉燃烧供热调控精准性与多孔介质区粘性阻力系数无关;预装适量型煤、孔对孔堆置型煤和封闭清灰口是反烧炉燃烧供热调控精准前提条件。该研究为反烧炉设计优化提供理论依据。更多还原

【Abstract】 Combined with porous media model and RNG k-epsilon turbulent flow model,numerical model for air flow in hot air furnace of clean coal reverse combustion for dense flue-cured tobacco had been established. Variation of air flow distribution and air utilization rate in furnace with height of coal bed,height of clean ash on side wall of static pressure area and degree of alignment of honeycomb holes of upper and lower briquettes were studied by using single factor simulation optimization method. Results showed that air utilization ratio was cubic function of air velocity,cubic function of coal bed height,quadratic function of clean ash mouth height and quadratic function of resistance coefficient in porous media area. Precision of controlling heat supply of reverse combustion furnace was independent of viscous resistance coefficient of porous media. Preloading proper amount of briquetting coal,pile-to-hole stacking briquettes and closed ash cleaning nozzles were some preconditions for accurate heating control of reverse combustion furnace. This study provided a theoretical basis for design optimization of reverse combustion furnace.更多还原