基于XPTV的流化床异形颗粒分布特性研究

Investigation on Cylindrical Particle Position Distribution in Fluidized Bed Using XPTV Method

构建了X光颗粒示踪(X-ray particle tracking velocimetry,XPTV)测量系统,建立了示踪颗粒的制备方法以及示踪颗粒位置与姿态取向的测量和误差评估方法。基于以上方法获得了不同气速下圆柱颗粒位置和姿态取向的分布规律,并阐述了以上分布规律与流型之间的内在联系。结果表明,流化床处于鼓泡流化时圆柱颗粒会形成内循环,颗粒中心线与竖直方向多呈倾斜状态;而处于湍动流化时圆柱颗粒则会在全床内趋于均匀分布,颗粒中心线趋于竖直方向。

An X-ray particle tracking velocimetry（XPTV） system is designed and built,and the corresponding tracer particle fabrication method is established.With the XPTV system,the cylindrical particle position and orientation determination method and its error evaluation are investigated.Experimental studies on cylindrical particle position and orientation distribution are carried out based on the aforementioned system and methods.The results show that in bubbling fluidization regime,an internal circulation of cylindrical particles forms in the fiuidized bed,and the center axes of most cylindrical particles tend to tilt instead of being vertical.In turbulence fluidization regime,cylindrical particles tend to uniformly disperse across the fiuidized bed,and the center axes of most cylindrical particles are vertical.