Measurement of separation performance and numerical analysis on flow field of different cyclone separators in parallel

doi:10.11949/j.issn.0438-1157.20160399

Abstract

Abstract:

Three different cyclone separators with diameter of 300 mm, PV-1, PV-2 and PV-3, were designed by changing either the direction of rotation or the diameter of vortex finder. PV-1 differed from PV-2 in the direction of rotation, while PV-3 differed from PV-1 in the diameter of vortex finder. These cyclone separators were assembled center-symmetrically in three paralleled arrangements as assembly of same cyclones (Parallel-Ⅰ), assembly of various rotation (Parallel-Ⅱ) and assembly of various vortex finder (Parallel-Ⅲ). Parallel-Ⅰ was consisted of four PV-1 cell cyclones; Parallel-Ⅱ was consisted of two PV-1 cyclones and two PV-2 cyclones; Parallel-Ⅲ was consisted of two PV-1 cyclones and two PV-3 cyclones. Separation performances of single cyclone and cyclone assemblies were studied in a cold state experimental setup under a condition of solid loading at 5 g·m^-3 and inlet velocities ranging from 14-26 m·s^-1. The flow fields in these paralleled cyclones were simulated with FLUENT software. The results show that paralleled cyclones had higher efficiency than single one with no hump in the curve of efficiency versus inlet velocity. Compared to Parallel-Ⅰ, Parallel-Ⅱ was lower in both total pressure drop and efficiency due to weaker swirl flow. Gas throughput was evenly distributed among each cell cyclone and no cross flow was observed in the common dust bin of either Parallel-I or Parallel-Ⅱ. However, Parallel-Ⅲ had higher total pressure drop than Parallel-Ⅰ. Because Parallel-Ⅲ was composed of cell cyclones with different vortex finder, gas throughput in Parallel-Ⅲ was no longer evenly distributed and an average deviation of about 6.0% was observed between the inlet and outlet of each cell cyclone. A cross flow in the common dust bin was also happened from PV-3 to PV-1, which forced some collected particles back to the inner flow, weakened the stability of vortex flow and decreased separation efficiency. Therefore, the same type of cyclone separators should be assembled center-symmetrically in parallel in order to ensure high separation efficiency of paralleled cyclones.

Key words: cyclone separator, in parallel, measurement, flow field, numerical analysis

摘要：

通过改变旋向和芯管直径，设计了3种差异旋风分离器，并按中心对称方式组成了3种并联方案：相同分离器、旋向差异分离器和芯管差异分离器并联。在冷态实验装置上，测量了单分离器和并联分离器的性能，并利用FLUENT软件分析了并联分离器的流场。结果表明，并联分离器的效率均高于单分离器，且效率-气速曲线未出现“驼峰”；与相同分离器并联相比，旋向交替变化时并联总压降较小，分离效率也更低，但各分离器流量分配均匀，未发现“窜流”现象；当芯管有差异时，并联总压降增大，各分离器进口流量分配不均匀，且进、出口流量平均相差6.0%，公共灰斗中存在“窜流”，旋流稳定性变差，效率降低。为了保证并联分离器的性能，应采用相同分离器对称并联的方式。

关键词: 旋风分离器, 并联, 测量, 流场, 数值分析

CLC Number:

TQ028.2

CHEN Jianyi, GAO Rui, LIU Xiulin, LI Zhenfa. Measurement of separation performance and numerical analysis on flow field of different cyclone separators in parallel[J]. CIESC Journal, 2016, 67(8): 3287-3296.

陈建义, 高锐, 刘秀林, 李真发. 差异旋风分离器并联性能测量及流场分析[J]. 化工学报, 2016, 67(8): 3287-3296.

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