摘要
采用计算流体力学软件FLUENT,选用Reynolds应力湍流模型和欧拉多相流模型,对国产首台1GW单切圆单炉膛塔式锅炉炉内的煤粉空气两相流动过程进行了数值模拟,得出了炉内各截面的速度场、假想切圆直径、浓度场、压力场及湍流动能Κ、湍流耗散率ε和湍流集中度Ι的分布。结果表明,颗粒呈螺旋上升趋势和螺旋沉降趋势,形成"W/M"流线型;炉膛出口切向速度剩余残量仅为该速度最大值的22.7%以下,在炉膛出口处的Κ、ε和Ι都比其他截面小,表明炉膛出口残余旋转很小;从下部水冷壁拐角处到上部煤粉燃烧器第3层之间的炉内四周壁附近区域是VOF密集区,该区域的水冷壁管易结焦;随着炉膛高度的增加,炉内的静压值越来越小。
The Reynolds Stress Model and Eulerian Model of The Computational Fluid Dynamics （CFD） code FLUENT was employed to evaluate the flow process field of two-phase between pulverized coal and air in a IGW single circle tangential firing single chamber boiler. The distribution of gas velocity field, the diameter of the imaginary tangential round, volume fraction field, static pressure field as well as turb-kinetic-energy（K）, turb-diss-rate （ ε ）, turb-intensity（I）, in the down, middle and upper zone of the furnace was obtained. The numerical results showed that particle was a spiral upward trend and spiral sedimentation trend, and formed a ＇W/M＇ streamline; The tangential velocity surplus residual in the chamber exports was only less than the maximum speed of 22.7%, at the same time, K, eand I in the exit of the chamber were smaller than in any other section, these shows that the residual swirling in chamber exports was small; from the comer of the down water-wall to the upper pulverized coal burners on the third floor of the furnace wall between nearby area is the concentration VOF region, the water-wall tubes around the region are easy coked. With the increase of furnace, the pressure value becomes bigger.
出处
《电站系统工程》
北大核心
2011年第6期1-5,共5页
Power System Engineering
