摘要
针对大容量电站锅炉中过热器和再热器集箱的径向引入引出三通结构进行了数值模拟,并运用Fluent软件,对稳态工况下径向引入引出三通结构的静压分布特点、流动机理、三通附近区域的流态对流量分配的影响进行了研究.结果表明:强三通效应在主母线方向、侧母线方向体现出不同的特征,主要原因是在三通区域存在3个明显的回流区,其共同作用决定了三通效应的影响模式;分流三通结构在三通附近受回流区的影响,Eu值均出现极小值,此处支管的流量驱动依赖于汇流集箱的压差补充,因而是危险区域,但其影响范围在2D内,故在布置支管时应考虑避开这一危险区.
Numerical simulation was carried out for the superheater and reheater headers with radial leading-in and leading-out tee-junctions in large capacity utility boilers. Using Fluent software, the static pressure distribution features, flow mechanism and effect of flow pattern near tee zone on flow distribution of radial leading-in and leading-out tee-junctions were studied under steady condition. Results show that the strong tee effects reflect defferent features in the direction of main generating line and side generating line. The main reason is that there are three obvious backflow zones near the tee. The coaction of the three backflow zones determines the influencing mode of the tee effect. The minimum Eu number exists near the distributing tee due to the effect of the backflow zone. The flow in the branch near the distributing tee depends on the pressure drop from the collecting header, thus the areas near the tee is the dangerous zone,but the influencing range is within 2D. It should be take into account to avoid this dangerous zone when branch tubes are arranged.
出处
《动力工程》
CSCD
北大核心
2009年第6期528-533,共6页
Power Engineering
关键词
锅炉
三通集箱
静压分布
回流区
流量分配
热偏差
数值模拟
boiler
tee-junction header
static pressure distribution
backflow zone
flow distribution
thermal deviation
numerical simulation
