水平管泡状流压力信号的功率谱特性比较

Power spectral characteristic comparison of pressure signals of bubbly flow in horizontal pipe

为比较Welch功率谱、AR功率谱和EV功率谱对气液二相水平管泡状流压力信号的功率谱分析效果,对泡状流压力波动信号进行了分析。将提取的泡状流压力波动信号经小波去噪后,分别进行Welch功率谱、AR功率谱和EV功率谱估计,并分析比较所得3种功率谱密度图。分析表明:Welch、AR和EV功率谱均能正确反映泡状流压力波动信号的功率谱特性,但有性能差别;由幅值、方差和分辨率3个方面的分析总结出对气液二相水平管泡状流压力信号AR功率谱具有最好的功率谱估计效果。

To compare the effects of Welch,AR and EV power spectral analysis on the gas-liquid two-phase bubbly flow pressure signal in a horizontal tube,the pressure fluctuation signal of bubbly flow was analyzed.After being denoised by wavelet,the pressure fluctuation signal of bubbly flow was respectively analyzed by Welch,AR,and EV power spectra,and then followed by the analysis and comparison of the three power spectral density figures.The analysis shows that Welch,AR and EV power spectra can all reflect power spectral characteristics of the pressure fluctuation signal of bubbly flow correctly,but their performances are different;the analysis from three aspects of amplitude,variance and resolution concludes that AR power spectrum has the best power spectral performance among the three methods to the gas-liquid two-phase bubbly flow pressure signal in a horizontal pipe.