基于床层下降的链条炉数值模型与计算

建立了考虑床层下降的链条锅炉二维稳态层燃数值模型,通过求解床层高度控制方程得到床层高度沿炉排前进方向变化的分布,利用动网格技术实现床层高度的下降。对比层燃模型和单元体炉实验结果,实验测得燃烧后床层高度为30 mm,改进后模型预测值为26.9 mm,表明改进后的模型可以更准确地预测床层高度、床层燃烧温度、气体产物分布,提高了层燃数值模型的计算精度。

Numerical Model and Calculation of a Chain-grate Stoker Based on a Descending of the Bed

A grate-firing model for chain grate stokers is an effective means for studying the mechanism governing the grate combustion.On this basis,established was a two-dimensional steady-state grate-firing numerical model for chain grate stokers with a descending of the bed being considered.By seeking a solution to the bed height control equation,obtained was the distribution of the bed heights varied along the going-forward direction of the chain grate.By utilizing the moving grid technology,the descending of the bed was realized.Through a comparison of the results obtained by using the grate-firing model and those obtained from a test of a unit body boiler,the bed height measured during the test after the combustion was 30 mm while the predicted value by using the model in question after an improvement was 26.9 mm,indicating that the improved model can predict more accurately the bed height,bed combustion temperature and distribution of the gas product,thus,enhancing the calculation precision by using the grate-firing numerical model.