某电厂汽包锅炉过热器顶棚管联箱结构优化研究

Geometrical Optimization for Outlet Tubes at Header of Top Roof Superheater in a Utility Boiler of a Power Plant

针对某电厂锅炉顶棚过热器频繁爆管现象,建立了与现场实际相同的几何模型,采用计算流体动力学方法对联箱内部流动情况进行数值研究。研究发现联箱三通附近由于静压分布异常,导致引入管周边的分支管静压较低,流量分配相对减少,发生传热恶化,进而发生爆管。该文提出优化的几何结构,通过对特定分支管引出方向进行调整,显著提升了并联分支管流量分配的均匀性,为电站锅炉分配联箱设计和结构优化提供一定的参考。

Numerical simulation was performed on the internal flow of header using the method of computational fluid dynamics with geometry model builded the same as practical field for the frequent rupture of roof superheater in a power station. The results indicate that due to the abnormal static pressure distribution in the area of Tee-junction of header, the static pressure of the branch pipes around inlet tube is so low, and the mass flow rate decreases relatively, then the heat transferation of tubes deteriorates, finally the tubes rupture. This paper proposes an improved geometric construction. By changing the leading direction of specific branch pipes, the uniformity of mass flow distribution in branch pipes promotes significient. It will offer a great reference for further design and optimization of distribution header in power station boilers.