射流作用下燃煤颗粒物团聚模拟研究

Simulation Study on Agglomeration of Coal Particles in Jet Flow

湍流团聚是颗粒团聚较有效的方式之一。利用Fluent软件对射流作用下的颗粒物湍流团聚情况进行模拟研究,将欧拉双流体模型与颗粒群平衡模型结合,采用离散分区算法进行计算,结果发现气体射流有利于颗粒物碰撞团聚,有效提高了颗粒物清除率。团聚室内不同气氛下的颗粒物团聚计算表明,氮气与二氧化碳混合气(体积比4∶1)最有利于颗粒物的清除,而二氧化碳气氛下颗粒清除率最低。团聚温度升高有利于颗粒物的团聚。颗粒物总清除率随气体相对湿度改变而变化,相对湿度达到40%时,颗粒清除率最高。

The agglomeration in turbulent flow was an efficient method improving the removal of fine particles. The agglomeration process was calculated using the Fluent commercial software. The coupling of Euler-Euler two-fluid model and popular balance model was used to simulate the agglomeration process. Partition algorithm method was used to solve these equations. The results showed that gas jet was favorable to the collision agglomeration of fine particles,which could effectively improve the particle removal rate. For the influence of agglomerative atmospheres,the highest removal efficiency was occurred in the mixture atmosphere of nitrogen and carbon dioxide( 4∶1 in volume),while the lowest value was in carbon dioxide atmosphere. Increasing temperature could favor the agglomeration process. The relative humidity of gas could affect the removal efficient. When the relative humidity was about 40%,the removal efficiency of particles was the maximum value.