集合管端部结构对重整加热炉管系流量分布影响

Impact of manifold end structure on flow distribution of tube system of reforming furnace

重整加热炉集合管不同的盲端结构参数对各炉管间的流量分布影响较大。利用数值模拟计算软件ANSYS-CFX,采用标准的k-ε双方程湍流模型,对具有不同盲端距离和工程上经常采用的几种盲端结构的重整加热炉管系内的介质流量分布进行模拟计算。数值模拟结果表明:CFX软件能较准确地模拟重整加热炉炉管内的流场;对于简单的法兰盖直接密封盲端结构,由于气相物流的周期性压缩和膨胀,盲端距离既不能太小也不能太大,存在一个最佳值;带有偏心大小头的盲端结构具有稳流作用,端部物流相对稳定,管系流量分布相对最优,应该优先选用。数值模拟得出了重整加热炉集合管的优选端部结构,同时可以为重整加热炉管系工程设计提供理论指导。

The different blind end structures of manifold of reforming furnace have a great impact on the flow distribution of furnace tubes. The medium flow distribution in reforming furnace tubes of different blind end structure and different blind end spacing are simulated by using numerical simulation software ANSYS- CFX and standard k-εturbulent model. The results of numerical simulation show that, the software CFX can accurately simulate the flow field in the tubes of reforming furnace. For the blind end structure with simple flange cap direct seal, the pacing of blind end can not be too large or too small and an optimal spacing should be selected because the gas-phase effluent will periodically expand and be compressed. The blind end struc- ture with eccentric reducer, which is stable in effluent flow and optimal in flow distribution, should be first se- lected. The optimal end structure for the manifold of reforming furnace has been worked out by numerical sim- ulation, which provides a good reference for engineering design of tubing system of reforming furnace.