气流床气化炉水冷壁的水力特性

Hydraulic Characteristics of Membrane Wall in an Entrained-Flow Gasifier

基于实验室小型水冷壁气流床气化炉,建立了工质流动及传热模型,对水冷壁的水力特性进行了研究,并分析了结构参数、操作参数对工质不均匀性的影响。模拟结果表明:分配集箱中沿流向工质速度逐渐降低,静压逐渐升高;汇集集箱中沿流向工质速度逐渐增大,静压总体呈降低趋势。与集箱进口距离较远的冷却管的进、出口压差相对较大,其中质量流量较高。缩小冷却管直径,增大管间夹角均可改善工质不均匀性。随集箱入口速度的增加,工质的不均匀性加剧;而改变入口工质的温度对其不均匀性无显著影响。

Based on a bench-scale membrane wall entrained-flow gasifier,a flow and heat transfer model of working fluid was established for the study of hydraulic characteristics of the membrane wall.The effects of structure parameter and operating parameter on the working fluid maldistribution were also analyzed.The simulation results show that velocity of working fluid decreases while static pressure increases along flow direction in the distribution header.In the collection header,the velocity of working fluid gradually increases along flow direction,while the static pressure decreases in the same direction.Higher inlet-outlet pressure drop and flow rate are observed in the cooling tube which is farther from the header inlet.The maldistribution of working fluid can be reduced by diminishing the cooling tube diameter and enlarging the angle between the tubes.The maldistribution increases with the increasing inlet velocity of working fluid.Changing the inlet temperature of working fluid has negligible effect on its maldistribution.