回转窑筒体非稳态传热过程的数值模拟

Numerical Simulation of the Unsteady Heat Transfer in the Rotary Kiln Shell

在对回转窑传热过程进行分析的基础上,以某氧化铝厂4.5×90m的回转窑作为研究对象,建立了关于窑横截面筒体非稳态传热过程的二维数学模型,然后对窑筒体温度沿径向的分布和窑壁内表面温度随时间的变化情况进行了数值模拟计算。模拟计算结果表明,当回转窑操作正常时,窑筒体外表面的散热损失基本不变。若将窑筒体的蓄热、放热周期过程作为整体考虑,则回转窑内的换热过程可以简化为稳态换热,窑筒体径向温度可视为线性分布。

Based on the analyses of rotary kiln heat transfer process, taking φ4.5×90malumina rotary kiln, a twc^di mensional model of the unsteady heat transfer in the kiln shell is established. Then kiln shell radial temperature distribu- tion and the inner wall temperature variation have been simulated, numerically. The computation results show that the heat loss of kiln shell surface remain approximately unchanged when the rotary kiln operation is in the normal state. The heat transfer process of kiln shell can be simplified as a steady process in endothermic period and exothermal period, and the radial temperature profile in kiln shell can be regarded as a linear distribution.