借助包括双欧拉均相多相流模型、VOF界面追踪方法和SST k-ω湍流模型的CFD模型,对孔盘式液体分布器内的流场对布液孔出流均匀性的影响进行研究。首先以单孔流动时的液体流量为标准值,通过与标准值的偏差来评估布液孔的出流不均。根据偏差的大小,可以衡量分布器内流动对布液孔出流的影响。然后结合孔前流动区概念对模拟结果进行分析,发现布液孔出流不均是由分布器内液体流动不均造成的。最后,提出了通过改变进料管位置来优化盘式液体分布器结构。计算结果表明,改变进料管的位置可以避免大规模不良分布,进而提高液体分布器的性能。
A computational fluid dynamics (CFD) simulation, consisting of a homogeneous multiphase model, VOF method and SST turbulence model, was performed to investigate the influence of the flow in orifice pan liquid distributor on the uniformity of outflow through orifices. Firstly, a deviation from the standard value (flow rate of outflow through single orifice) was proposed to evaluate the uniformity of outflow through orifices. The influence of the flow in distributor on the outflow through orifices was quantified by the value of the deviation. Subsequently, based on the simulated results and the concept of the flow region in front of the orifices, it was found that the non-uniformity of the outflow through orifices was caused by the non-uniformity of the flow in distributor. Finally, the structure of the orifice pan liquid distributor was optimized by changing feed pipe positions. The simulated results showed that the liquid distribution performance was improved because the large-scale maldistribution was avoided when the feed positions were changed.