浅层单管气-固流化床内对流换热的数值模拟  

Numerical Simulation of Convective Heat Transfer in Shallow Single Tube Gas-Solid Fluidized Bed

作　　者：李伟栋[1] 李菊香[1] 

机构地区：[1]南京工业大学能源学院,江苏南京211816

出　　处：《工业炉》2013年第5期49-52,58,共5页Industrial Furnace

摘　　要：应用欧拉双流体模型对内埋单支换热管的浅层气-固(空气-石英砂颗粒)流化床进行了数值模拟,在换热管周围建立了4个观测点,得出了沿换热管圆周方向流动状况和局部瞬时换热系数的变化。结果显示:在换热管中心水平面的左右两侧壁面处颗粒更新速度较快,并有气泡上升,局部换热系数的变化也较强烈;在管壁下部颗粒运动相对平稳,并有颗粒在此滞留,局部换热系数变化相对较缓;在管壁上部颗粒有堆积,这使得颗粒体积分数在此处变化较小,局部换热系数变化也较为平缓。The Eulerian-Eulerian two-fluid model is applied to simulate a shallow gas- solid （air and silica sand particles） fluidized bed with a single tube. Four monitoring points are created at four different locations the tube, and the changes of the flow and local instantaneous heat transfer coefficient along the circumferential direction of the heat exchange tube are obtained. The results show that the particle update rate is fast with rising bubbles and the local heat transfer is stronger at the left and right sides around the heat exchange tube center horizontal. The particles motion is relatively steady with particle retention and the local heat transfer coefficient change is relatively slow at the bottom of the tube wall. The particle volume fraction changes small with particle accumulation at the top of the tube wall and the local heat transfer coefficient changes gently, too.

关 键 词：浅层气固流化床 欧拉双流体模型 对流换热 数值模拟 

分 类 号：TK124[动力工程及工程热物理—工程热物理]