小波分析方法在喷动床流型识别中的应用

发布时间：2018-10-09 16:09

【摘要】：在直径150 mm、静床层高280 mm的柱锥形喷动床中,采用平均粒径为1 mm、密度为2 770 kg/m~3的刚玉球为实验固相,采集不同气速下无导流管和带开孔导流管喷动床中的压力信号,通过小波分析与功率谱相结合的方法表征柱锥形喷动床的流型转变。首先利用平均压力法测得本实验条件下无导流管和带开孔导流管喷动床的最小喷动速度分别为0.57,0.50 m/s,然后采用Daubechies2小波对压力信号进行7层小波分解得出能反映喷动床流动特性的主频信号,再对主频信号进行功率谱分析。结果表明:无导流管和带开孔导流管喷动床的主频分别出现在D3(6.25—12.5 Hz)和D2(12.5—25 Hz)频段,且主频信号的功率谱图可以表征喷动床的3种流型:固定床、稳定喷动和不稳定喷动;开孔导流管喷动床的操作弹性(1u_g/u_(ms)1.23)明显比无导流管喷动床的操作弹性(1u_g/u_(ms)1.12)大。
[Abstract]:In a cylindrical conical spouted bed with a diameter of 150 mm, a corundum ball with an average diameter of 1 mm, density of 2 770 kg/m~3 was used as the experimental solid phase to collect the pressure signals in the spouted bed without and with openings at different gas velocities. The flow pattern transition of a cylindrical tapered spouted bed is characterized by wavelet analysis and power spectrum. The mean pressure method was used to measure the minimum spouted velocity of the spouted bed without and with openings in this experiment, respectively. Then the Daubechies2 wavelet was used to decompose the pressure signal with 7 layers wavelet decomposition to show that the spouted velocity could reflect spouted motion. The main frequency signal of the bed flow characteristics, Then the power spectrum of the main frequency signal is analyzed. The results show that the main frequency of spouted bed with no diversion tube and orifice tube appears in D3 (6.25-12.5 Hz) and D2 (12.5-25 Hz) frequency range, and the power spectrum of main frequency signal can characterize three flow patterns of spouted bed: fixed bed, stable spouted bed and unstable spouted bed. The operating elasticity of the spouted bed (1ug / u _ (ms) 1.23) is obviously greater than that of the spouted bed without the tube (1ug / u _ (ms) 1.12).
【作者单位】：河北工业大学化工学院;河北工业大学海洋科学与工程学院;
【基金】：河北省科技支撑计划(14273105D) 河北省自然基金资助项目(D2014202074) 河北省高等学校青年拔尖人才计划项目(BJ2016016)
【分类号】：TQ051.1

【相似文献】