循环流化床锅炉密相区内颗粒的横向扩散研究

以热粒子作为示踪粒子，用热电偶测量示踪粒子沿径向的变化，在长900mm、宽100mm、高5200mm的循环流化床密相区进行了颗粒的横向扩散的研究。循环流化床密相区内颗粒横向扩散可用一维扩散模型来描述，模型的计算结果与实验数据吻合很好。根据实验数据拟和得到颗粒的横向扩散系数Dsr，实验表明随着流化风速的增大和静止床高的增高，横向扩散系数Dsr增大；随颗粒粒径的增大，横向扩散系数Dsr减小。最后给出了以流化风速、静止床高和颗粒粒径为影响因素的横向扩散系数Dsr的经验式。

A Study of the Transverse Dispersion of Solid Particles in the Dense-phase Zone of a Circulating Fluidized Bed Boiler

With hot particles serving as tracer ones the radial variation of the latter was measured by the use of thermocouples. A study of the particle transverse dispersion has been conducted in the dense phase zone of a circulating fluidized bed, which has the following dimensions: length 900 mm, width 100 mm and height 5200 mm. The particle transverse dispersion in the above cited zone can be described with the help of a one dimensional dispersion model. The model calculation results are in very good agreement with experimental data. Through the experimental data fitting one can obtain the particle transverse dispersion factor Dsr. The tests show that with the increase in fluidizing air speed and stationary bed height there will be an increase in the transverse dispersion factor. The transverse dispersion factor will decrease with the increase in particle diameter. Finally, an empiric formula was given for the transverse dispersion factor with the fluidizing air speed, stationary bed height and particle diameter serving as influencing factors.