旋风炉内气相燃烧及两相流动的数值模拟

摘要

On the basis of the previous pure two-fluid model for turbulent reacting gas-particle flows with combusting pulverized coal particles ,a new comprehensive model for pulverized coal combustion was developed by incorporating a modified k-e-kp model ,a general model of pulverized coal devolatilization and a general model of char combustion. As the first stage of numerical modeling of pulverized coal combustion in the cyclone combustor,three dimensional simulation of turbulent gas combustion and gas-particle flows have been made, the predicted results show that there is a near wall recirculating zone at the bottom of the cyclone combustor,and the recirculating zone is beneficial to ignition and flame stabilization. The predicted tangential velocity distribution of both gas phase and particle phase was similar to Rankine vortex.%在有反应两相流动及煤粉燃烧的全双流体模型(PTF模型，pure two-fluid model)基础上，采用修正的k-ε-kp两相湍流模型，对旋风炉内的湍流气相燃烧(甲烷和一氧化碳的燃烧)及在气相燃烧条件下的两相流动进行了数值模拟研究，模拟结果表明，在有燃烧的情况下，在旋风炉的底部存在近壁回流区，该回流区有利于火焰稳定。气粒两相切向速度分布具有类似的Rankine涡结构。该研究为煤粉燃烧的数值模拟奠定了基础。