摘要
本文主要介绍了燃煤循环流化床燃烧的数学模型.采用本模型可以算出固体颗粒运动轨迹、固体颗粒浓度分布、气体成份分布、燃烧效率、碳浓度分布、温度分布、传热系数和释热率分布等,以及这些参数随运行工况的变化规律.计算结果与实验结果的对比表明本模型可以合理地估计各种不同运行参数对与上述各过程的影响,当然某些参数在定量计算上的准确性尚有待进一步的发展.
A comprehensive mathematical model for circulating fluidized bed combustion process of coal, which has properties of block-removability, validity and preliminaries, is introduced in the paper. The model is liable to be further developed and describes CFB combustion process of coal comprehensively and correctly. In the comprehensive model, the hydrodynamic model is composed of three main parts, the fluctuation spectrum random trajectory submodel, two-channel solid particles concentration submodel and particle collision submodel. In order to make the model better universality, the heating process, evaporation process, devolatilization process, and heterogeneous combustion process are successively considered in the submodel while coal particles entering the CFB bed. In heterogeneous combustion submodel, particlee size remains contant in char combustion process for low ash coal and dual-shrinking char combustion submodel is used for high ash coal. With the model, we can obtain some information about the solids particle trajectory, solid concentration profile, gasseous concentration profile, the combustion efficiency, the carbon content distribution, the temperature profile, the hear transfer and heat release conditions, etc. and the influences of various factores to above parameters. Tentative calculation has shown that the model can reasonably predict the effects of various operation conditions on combustion process with some acuracy.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
1993年第1期92-96,共5页
Journal of Engineering Thermophysics
