高温熟料非稳态非热平衡渗流换热模型

回转窑卸入篦冷机的高温水泥熟料为红热半透明的多孔介质,其复杂的气固换热机理给篦冷机的工艺改进带来较大难度。针对这一问题,将高温红热颗粒等效为光学厚介质,推导了一种高温熟料颗粒间传导与辐射综合换热系数,基于渗流力学与传热学理论,建立了考虑高温熟料颗粒间热辐射效应的水泥熟料非稳态非热平衡渗流换热模型。通过对所建模型进行求解,得到了料层内熟料温度与气体温度的分布规律,比较了不同区域冷却速率的差异,获得了辐射传热因素对料层温度分布的影响。

Seepage Heat Transfer Model with Thermal Non-equilibrium of High Temperature Clinker

The high temperature cement clinker can be regarded as glowing red and translucent porous media when it is discharged from rotary kiln to grate cooler. It brings greater difficulty to technology improvement of grate cooler since the gas-solid heat transfer mechanism is complex. According to the problem, the glowing red particle can be equivalent to optically thick medium, then an integrated heat transfer coefficient is derived for high temperature clinker particle when heat conducting and thermal radiating. Based on the seepage mechanics and heat transfer theory, an unsteady seepage heat transfer model with thermal non-equilibrium of cement clinker is built which considering the heat radiation effect between the high temperature clinker particle. By solving the model, the distribution of clinker temperature and gas temperature inside the material layer are obtained, at the same time, the difference of cooling rates in different regions are compared to gain the impact of radiation heat transfer factor on the material layer temperature distribution.