气力输送流型与压力信号关系研究

Relationship Between Pneumatic Conveying Flow Pattern and Pressure Signal

以压缩空气作为介质,在内径为65 mm的管中分别进行稀相与密相气力输送实验,并据此研究了压力信号与流型的关系。通过分析压力信号的波动和功率谱密度,发现压力信号与颗粒输送流型存在密切关联。研究表明:密相气力输送系统压力信号的波动范围和波动标准差均远大于稀相输送;并且密相气力输送系统压力信号的概率密度分布分散,总体呈现典型的正态分布特征;通过分析压力信号的功率谱发现,稀相气力输送系统的压力信号以低频信号为主,而密相气力输送系统的压力信号在高、中、低频段均有分布。

Dilute phase and dense phase pneumatic conveying experiments,driven by compressed airflow,were carried out in 65 millimeters inner diameter pipe.According these,the relationship between pressure signal and flow pattern has been studied.By analysis of the fluctuation and power spectral density of the collected pressure signal,it is found that the pressure signal is closely related to the flow pattern of particle conveying.The results show that the fluctuation range and standard deviation of pressure signal of the dense phase pneumatic conveying system are significantly greater than that of the dilute phase conveying system.The probability density distribution of pressure signals in dense phase pneumatic conveying system gently distributed as a typical normal distribution.Meanwhile,it is found that the pressure signals of dilute phase pneumatic conveying system are mainly low frequency signals by power pressure signal spectrum analysis,while the pressure signals of dense phase pneumatic conveying system are distributed in all frequencies.