超临界循环流化床下降水冷屏流量分配特性试验研究

针对350 MW超临界循环流化床锅炉的结构参数,建立空气-水试验台,模拟了超临界循环流化床锅炉在25％、50％和70％3种额定负荷下气液两相流在下降水冷屏并联支管中的分配特性.采用快关阀门法和分相测量法分别测量了下降水冷屏各并联支管内的体积流量含气率分布、干度分布、各相流量分布和差压分布.试验发现:在进口集箱干度为0.3～0.9的范围内,25％负荷下的体积流量含气率、千度分布和差压分布最均匀,并且随着锅炉负荷的增加,各并联支管内的相分配偏差增加；25％负荷下各并联支管内各相的流量分配均匀性最差,并且随着锅炉负荷的增加,各并联支管内流量分配均匀性得到改善.

Distribution Characteristics of Downward Water-Cooling Panel in Supercritical Circulating Fluidized Bed Boiler

An air-water test-bed was designed according to the configuration and parameter characteristics of the water-cooling panel of a supercritical circulating fluid bed boiler to study the flow distribution characteristics of the water-cooled screen at three operational loads of 25% ECR,50% ECR and 70% ECR,respectively.The volumetric fractions of air content,the quality distribution,the phase flow distribution,and the pressure distribution in each branch were measured by the quick-close valve method and the phase measurement method.The results show that the volumetric fraction of air content,the quality distribution,and the pressure distribution in the parallel branches were most uniform at the load of 25% ECR when the inlet quality was 0.3-0.9.The deviation of the phase distribution in the branches increased with an increase in the load.In addition,the uniformity of the flow distribution increased with the load,indicating that the flow distribution was the worst at the load of 25% ECR.