曾宪钰+袁益超+徐国鹏+闫绍兵

摘要：为了获得过热器和再热器T型三通对集箱静压分布及三通两侧分流比对涡流区和集箱静压分布的影响规律，以空气为工质对纯三通模型进行流动特性试验.研究结果表明：带三通集箱静压分布受一次涡流和二次涡流的共同影响，一次涡流影响范围为-2.5D～2.5D（D为等径三通内径），二次涡流影响范围为-1.5D～1.5D；三通两侧分流比对涡流区范围影响较小；随着三通某侧流量增大，该侧静压降低，但静压分布规律无明显变化.在一次涡流影响范围内，正母线和右下40°线的静压差异受分流比的变化影响较小；侧母线的静压差异随分流比的增大而有所增大.

关键词：T型三通； 集箱； 静压分布； 涡流区

中图分类号： TK 223 文献标志码： A

Abstract：Abstract： Experimental study on the flow characteristics of Tjoint model using air as working fluid were conducted to get the influence of Tjoint on the static pressure distribution in the header of boiler superheater and reheater as well as the influence of split ratio on the both sides of Tjoint on the vortex zone and static pressure distribution. The results showed that the static pressure distribution in Tjoint was affected by the first vortex and second vortex. The range affected by the first vortex was from -2.5 to 2.5 times inner diameter of Tjoint. The range affected by the second vortex was from -1.5 to 1.5 times inner diameter of Tjoint. The split ratio on both sides of Tjoint had little effect on the range of vortex. As the flow rate increased on one side of Tjoint，the static pressure on this side decreased. However，there was no significant changes of static pressure distribution. In the range affected by the first vortex，the split ratio had little impact on the static pressure difference at the position of positive generatrix and at lower right line of 40 degrees，while the static pressure difference at the position of side generatrix increased with the rising of split ratio.

Keywords：Tjoint； header； static pressure distribution； vortex

随着电站锅炉向大容量高参数发展，过热器和再热器系统更加复杂，其受热面超温爆管的问题更需重视.目前大容量电站锅炉过热器和再热器的蒸汽引入、引出管多采用T型三通结构，由集箱径向引入、引出.因为在集箱上采用多点径向引入、引出方式，与单点轴向引入、引出方式相比而言，可以降低集箱中工质流速，使静压变化减小，从而减小流量偏差.但该方式也存在问题：在分配集箱T型进口三通附近的蒸汽流中存在涡流区，使得该区域管屏中蒸汽流量偏小，如果这部分管屏的烟气侧热负荷较高，就很容易发生超温爆管[1]，严重影响锅炉机组运行的安全性.

针对蒸汽径向引入、引出“三通效应”问……