低温省煤器入口联箱工质流动分析

Analysis on Flow in Influent Header of Low-temperature Economizer

不同结构来流管对联箱内工质流动影响较大,对运行经济性及设备安全意义重大。利用Fluent软件对直管来流与弯管来流的流动对联箱内部流动的影响进行研究,在不同入口工况0.60,0.66,0.72,0.78 m/s下,采用k-εRNG湍流模型,对比联箱中心截面速度分布,根据各支管平均出口速度Vi、支管压降Δpi分布和轴线X方向分速度Vx大小进行分析。结果表明,弯管来流的流动较为单一,主流冲击联箱壁面情况较少,在不同的工况下,弯管来流的支管速度不均匀性仅为直管的44%左右,采用弯管来流能够明显提高联箱流量分配的效果。

The structure of inlet pipe has a great influence on the flow inside the header, which could cause an economy and safety drop of the whole equipment. The Fluent software was used to study headers of vertical inlet and curved inlet pipes, with the different flow rates of 0.60 m/s ,0.66 m/s ,0.72 m/s and 0.78 m/s set and the turbulence model of k - ε RNG was used. By studying the distributions differences of velocity in centre section, average outlet velocities of branch pipes Vi, pressure drop Apiand the velocity along axis X Vx. The conclusion was made that flow in the header of vertical inlet was more complicated, and the flow impacted against the wall more. All of flow rates, branch pipe velocity nonuniformity of verti- cal was only 44% of the curved, it could better the flow rate distribution of the header.