摘要
为了减小锅炉水冷壁热偏差，防止发生局部超温和爆管，超超临界锅炉常在水冷壁管人口段加装节流孔板来调节各水冷壁回路的流量，如图1所示。但是锅炉在投运一定时间后经常发生节流孔板结垢问题，造成水冷壁超温和爆管事故，严重影响安全运行。因此必须对孔板进行定期除垢，目前主要采用酸洗的方法[2]，但这种方法会对汽水循环中的其他设备造成一定程度的腐蚀和损害，影响其运行安全性和寿命。
In order to solve the overheating and tube failure problems caused by deposits accumulated on the orifices in waterwalls of ultra-supercritical boilers,numerical models of a sample orifice are established based on the FLUENT platform after the analysis on the deposition mechanism.A detailed description of the flow field near the orifice is obtained with the help of the vector plots and the pressure contours.Trajectories and concentration distributions of particles injected from different sites are calculated and analyzed.The results indicate that precipitation and deposition of magnetite caused by the sharp pressure drop near the orifice surface is the main reason for the deposition problem.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2011年第7期1873-1878,共6页
CIESC Journal
