循环流化床锅炉膜式水冷壁管与鳍片上的温度分布

研究了循环流化床锅炉膜式水冷壁管的传热，并通过采用二维传热分析方法，讨论了带有竖直鳍片和横向鳍片的水冷壁管上温度与热流分布。探讨了炉膛侧传热系数、水冷壁管水侧传热系数、水温、床温、水冷壁管材的导热率以及竖直鳍片部最高，然后逐渐下降，但在横向鳍处理的根部又会上升。为了验证传热分析的真实性，在1台6MWth循环流化床锅炉膜式水冷壁管的横裁面内安置了0.8mm的热电偶，测量子水管横截面上的一些点的温度。实际测量值符合得相当好。

Temperature Distributions in A Finned Water Wall Tube of A Circulating Fluidized Bed Boiler

Heat transfer improvement in a water wall tube with fins is investigated in a circulating fluidized bed(CFB). The distributions of temperature in the metal wall and that of heat flux around the outer wall of a tube with a longitudinal and lateral fins are examined by a two dimensional heat conduction analysis. Effects of bed to wall heat transfer coefficient, water to tube inside heat transfer coefficient, bed temperature, water temperature and thermal conductivity of the tube material on the heat flux around the water tube are discussed. The present work also examined the influence of the length of longitudinal fin and the water tube thickness. Heat flux was highest at the tip of the longitudinal fin. It dropped, but increased again near the root of lateral fin. To verify the reliability of the heat conduction analysis, temperature at some discrete points within wall cross section of the tube was measured. 0.8mm thermocouples were buried within the tube cross section in a 6MWth CFB demonstration boiler. Measurements agree well with the predicted results. Figs16, table1 and refs10.