【摘要】 工业锅炉的积灰结渣影响炉内燃烧和传热,降低锅炉热效率。针对工业锅炉积灰结渣问题,建立了考虑飞灰输运、碰撞和黏附过程的链条炉飞灰沉积三维数值模型,结合实验得到的链条炉床层表面飞灰析出特性,预测某时间段内炉膛内不同位置的飞灰沉积量和灰渣厚度。模型预测的结渣部位与实验测量结果一致,链条炉后拱和喉口上方对应的前墙和侧墙是积灰结渣严重的区域。模型预测的结渣厚度较实验测量值偏低,进一步准确测量床层表面飞灰析出量可以提高结渣厚度的预测精度。通过对模拟结果进行分析,提出了防止积灰结渣的措施。更多还原

【Abstract】 The ash deposition and slagging in an industrial purpose boiler affects the combustion and heat transfer in the furnace and lowers the thermal efficiency of the boiler.With a view to solving the problem of the ash deposition and slagging in the boiler,established was a three-dimensional numerical model for calculating the fly-ash deposition in a chain grate stoker with the fly-ash transmission,collision and cohesion process being taken into account.In combination with the fly-ash precipitation characteristics on the bed layer surface of a chain grate stoker obtained through tests,the fly-ash deposition amount and ash/slag thickness at different locations in the furnace in a time duration were predicted.The slagging locations predicted by using the model in question are in agreement with the test ones.The front and side wall corresponding to the rear arc and the upper portion of the chain grate stoker are regarded as the areas with serious ash deposition and slagging.The slagging thickness predicted by using the model is excessively lower than the test one.To measure the fly-ash amount precipitated at a higher precision can enhance the prediction precision of the slagging thickness.Through an analysis of the simulation results,measures for preventing the ash deposition and slagging were given.更多还原