流化床是碳纳米管宏量制备的一个关键设备,对100mm管径无分布板式流化床内碳纳米管的压力波动进行小波分析。通过对不同操作条件下的床层压力波动信号进行小波分析,发现不同高度的压力信号可反映不同区域的流态,改变信号采集点的高度可对不同流态的出现进行监测。随着采集探头在径向的深入,锥部流态对压力的影响增大。通过关注部分子信号能量的波动,小波分析可以精确地对不同种类、不同初始床高的碳纳米管流态进行监控。
The fluidized bed is a key equipment for the macro-preparation of carbon nanotubes.In this paper,wavelet analysis of the pressure fluctuation of carbon nanotubes in a non-distributed plate fluidized bed with a diameter of 100mm was performed.Through wavelet analysis of bed pressure fluctuation signals under different operating conditions,it was found that pressure signals of different heights could reflect the flow patterns in different areas,and changing the height of the signal collection points was able to monitor the occurrence of different flow patterns.With increasing depth of the acquisition probe in the radial direction,the influence of the flow pattern of the cone on the pressure increased.By observing the energy fluctuations of some sub-signals,wavelet analysis could accurately monitor the flow patterns of different types of carbon nanotubes with different initial bed heights.
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基金资助
国家自然科学基金项目(51676103);泰山学者工程项目(ts20190937)
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