Separation and Purification Technology ( IF 8.6 ) Pub Date : 2020-01-18 , DOI: 10.1016/j.seppur.2020.116588 Marek Wasilewski , Lakhbir Singh Brar , Grzegorz Ligus
The aim of this study was to analyse the effect of varying the vortex finder diameter and its insertion length on the flow field and overall performance in a square cyclone. A total of 15 different vortex finder configurations with 5 different diameters, each having 3 different insertion lengths, were analyzed. An in-depth analysis of flow field inside the separator was conducted by using stereoscopic particle image velocimetry (Stereo-PIV) and large eddy simulation (LES). The former makes use of two cameras that focused simultaneously over the region of interest to record the details of the flow field, whereas the latter approach directly resolves a large part of the flow and provides the three-dimensional time-dependent details of the turbulent flows. The results extracted from PIV and LES – viz. mean tangential, mean axial, and mean radial velocities – were compared, and good agreement was observed between the two. In addition, the separation efficiency and Euler number (Eu) were evaluated experimentally and by using LES. Conclusive results indicate that the geometric shapes of the vortex finder have a significant effect on the performance of square cyclone separators. Decreasing the diameter of the vortex finder resulted in a considerable increase in Eu compared to the base variant (maximal increase in Eu amounted to about 660%). However, increasing the diameter of the vortex finder decreased Eu by about 55%. An optimally configured geometry of the vortex finder increased overall separation efficiency by 16%.
中文翻译:
不同涡旋探测器配置的方形旋风分离器性能的实验和数值研究
这项研究的目的是分析在方形旋风分离器中改变旋涡发现器直径及其插入长度对流场和整体性能的影响。共分析了15种具有5种不同直径的涡流探测器配置,每种直径都有3种不同的插入长度。通过使用立体粒子图像测速仪(Stereo-PIV)和大涡模拟(LES)对分离器内部的流场进行了深入分析。前者利用两个同时聚焦在感兴趣区域上的摄像机来记录流场的细节,而后一种方法直接解析大部分流,并提供湍流的三维时间相关细节。从PIV和LES中提取的结果–即。平均切线,平均轴向,比较了平均径向速度和径向速度,两者之间观察到了很好的一致性。另外,分离效率和欧拉数(Eu)通过使用LES进行实验评估。结论性结果表明,涡流探测器的几何形状对方形旋风分离器的性能有重大影响。降低旋涡溢流管的直径导致相当大的增加Eu的相比于基础变体(在最大增加Eu的达约660%)。但是,增加旋涡仪的直径会使Eu降低约55%。涡流探测器的最佳配置几何形状使整体分离效率提高了16%。