流化床辐射换热机理研究

On the Mechanism of the Radiation Heat Transfer in Fluidized Beds

本文通过对高温流化床内辐射传热特点进行分析,提出了颗粒堆积多层反射模型.径与劣质煤流化床锅炉的实验结果相比较,证明该机理模型能有效地计算大颗粒流化床中的辐射分量.

A new model of mechanism for calculating the radiation neat transfer between the immersed surfaces and high temperature fluidized beds is proposed. The particle packet with multi-layer reflection is adopted and the influence of temperature reduction of the particles adjacent to the walls has been considered in the model. With given voidage of the particle packet and particle emissivity, the equivalent radiation properties of the fluidizet bed can be obtained. This model can be used in combination with the convection and conduction models proposed by the authors to calculate the heat transfer coefficients in large particle fluidized beds and to predict the influences of the temperatures of bed and immersed surfaces.