超临界直流锅炉变压运行下水冷壁中间分配集箱的流量分配特性

Flow Distribution Characteristics of Intermediate Headers of a Supercritical Once-through Boiler's Water Cooled Walls,Operating Under Variable Pressure Conditions

研究了国产600 MW直流锅炉水冷壁中间分配集箱在亚临界压力下的流量分配特性。试验参数为：压力p=12-21 MPa,质量流速G=400-1200 kg/（m^2·s）,质量含汽率x=0-1.0。试验结果表明：随着分配集箱工作压力和分配集箱进口质量流速的增加,分配集箱并联支管之间流量分配的偏差降低;在入口质量含汽率较小时,并联支管间的流量分配偏差随着质量含汽率的增加而增大;在入口质量含汽率大于0.6时,并联支管间的流量分配偏差随着入口质量含汽率的增加而减小。

Flow distribution characteristics, of intermediate distribution headers between water walls, under sub-critical pressure conditions, of a domestic manufactured 600MW once-through boiler, has been studied. The effect of the medium＇s pressure on flow distribution characteristics, in the vertical water wall tubes connected with the header, was studied under the following conditions： pressure p = 12 - 21 MPa, mass flow G = 400 - 1 200 kg/m^2 ·s, steam content x = 0 - 1.0. Results show that the non-uniformity, of flow distribution among the parallel connected branch pipes, reduces with the header＇s increasing pressure and the inlet mass flow. In case the inlet mass flow contains little steam, then flow distribution non-uniformity in the branch pipes increases with increasing steam content; but as soon as the inlet steam mass content exceeds 0.6, non-uniformity of flow distribution decreases with increasing steam content at inlet.