Experimental investigation on particle flow characteristics in spouted bed with longitudinal vortex generator

doi:10.11949/j.issn.0438-1157.20171705

Abstract

Abstract:

Longitudinal vortex effect was created by attaching a longitudinal vortex generator to spouted bed so as to improve radial and axial motions of particles in conventional spouted bed. Particle image velocimetry (PIV) was applied to explore effects of longitudinal vortex flow and particle physical properties on radial velocity of particles in injection and annular zones of a 152-mm-diametered spouted bed. The results show that a lot of secondary vortexes appear in the cross section above flow disturbance element of the vortex generator and particle radial velocity is significantly intensified when compared to conventional spouted bed, indicating that the longitudinal vortex generator can enhance radial movement of particle phase in both injection and annular zones. Within the range of stable injection, smaller diameter and lower density of particles have better intensification effect of longitudinal vortex on radial motion of particles.

Key words: particle image velocimetry, longitudinal vortex, particle velocity, particle diameter, particle density

摘要：

针对喷动床内环隙区颗粒缺少横/径向运动的特点，通过实验将纵向涡流发生器及纵向涡流效应引入喷动床。采用粒子图像测速技术研究了在内径为152 mm的喷动床内纵向涡流及颗粒设计参数对喷动床内喷射区及环隙区颗粒相径向速度的影响，研究结果表明，纵向涡发生器在扰流元件上方横截面内颗粒相运动出现大量二次涡流，相比较于无纵向涡流扰流件情况，喷动床内的颗粒径向速度得到了显著增加，表明纵向涡发生器能够增强颗粒相在喷射区及环隙区的径向运动能力。在喷动床稳定喷动范围内，颗粒直径及颗粒密度越小，纵向涡流对颗粒相径向运动的强化效果越佳。

关键词: 粒子图像测速技术, 纵向涡流, 颗粒速度, 颗粒直径, 颗粒密度

CLC Number:

TQ021.3

SHANG Lingyi, WU Feng, MA Xiaoxun. Experimental investigation on particle flow characteristics in spouted bed with longitudinal vortex generator[J]. CIESC Journal, 2018, 69(5): 1923-1930.

尚灵祎, 吴峰, 马晓迅. 带纵向涡发生器喷动床内颗粒流动特性PIV实验[J]. 化工学报, 2018, 69(5): 1923-1930.

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