Chaotic Characteristic Analysis of Oil-air-water Three-phase Flow in Vertical Upward Pipe Based on Image Grayscale Signals

Using number 35 lubricants, air and running water as experimental mediums, high-speed camera is applied to get dynamic images of the 6 typical flows for the oil-air-water three-phase flow in vertical upward pipe. Grayscale average values of each frame images are extracted to form the time series. Based on the values, the chaotic characteristic is analyzed. The autocorrelation function is applied to calculate the delay time, and simultaneously the attractor and chaos associated and HURST Exponent are also used to analyze the formation mechanisms of the flow patterns for the oil-air-water three-phase flow. The experimental result draws to the conclusion: the image grayscale signals of the oil-air-water three-phase flow in vertical upward pipe have chaotic characteristic, by which the several typical flow patterns of three-phase flow can be fully represented.