Dynamic Characterization Analysis of Gas/liquid Two Phase Flow

Yun cheng Du, Hua xiang Wang

School of Electrical Engineering and Automation Tianjin University, Tianjin, China

E­mail: mm7760@126.com

ABSTRACT

This work deals with the characterization of gas/liquid two phase flows based on multi­resolution analysis of wavelet transformation and Hurst analysis in order to develop objective flow regime indicators. The decomposition errors for different Daubechies wavelets were firstly discussed, and then the optimal wavelet was used for decomposing measured data obtained from electrical capacitance tomography system. For the approximate signal, the appropriate decomposition level was determined and statistical analysis of different decomposition levels were studied? furthermore, a wavelet based threshold criterion was developed to describe the flow regime characteristic. For the detail signals which reflect the properties of discrete phase, the Hurst analysis was adopted to reveal the bi­fractal behaviour for different flow regimes.

Keywords Flow regime characteristics; Wavelet; Hurst analysis; Electrical capacitance tomography