Non-Invasive Evaluation of Wavy Liquid Film

Abstract

The study presents the possible use of optoelectronic system for the measurement of values specific for hydrodynamics of two-phase gas very-high-viscosity liquid flow in vertical pipes. An experimental method was provided, and the findings were presented and analysed for selected values which characterise the two-phase flow.

Verification of methods for calculating the gas volume fraction in the vertical descending flow of two-phase gas-liquid mixtures

“…Based on the literature review [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][18][19][20][21][22][23][24][25][26][27][28], regarding the methods for determining the volume fraction of gas in two-phase flows, it was noticed that many methods have particular ranges of their use and various forms of equations that do not allow for a direct comparison of individual calculation methods. An attempt was made to assess the applicability of selected calculation methods for typical two-phase systems: − water-air, − ethanol-air, − glycerin-air.…”

Downward Annular Flow of Air–Oil–Water Mixture in a Vertical Pipe

“…The multiphase mixture produced in a mixing chamber (K) initially flowed through the opaque section of the test channel (10) where the flow stabilized and flow patterns formed. In the transparent part of the measuring channel (3), the observation and identification of flow patterns were performed, combined with measurements of the void fraction of the phases conducted using the trap method (5,6,7). A system of electrical conductivity probes (15) was used for the determination of the dominance of oil or water phase in the flow.…”

“…The vertical coordinate of the new flow regime map is the volume concentration of oil in liquid βo*, while the horizontal coordinate is the three-phase mixture velocity j3P. Three-phase flow velocity is calculated as the total of the superficial gas velocities and both liquid phases in the flow, i.e., air, water and oil, according to Equation (5). The value of the concentration of oil in liquid is a value that determines the mutual relations of water and oil in a liquid two-phase stream according to the following equation * = ; * + * = 1…”

“…Based on the current state of the art, it is difficult to generalize the description of the complex phenomena occurring during such a flow. 5 Pleshko et al [17] (1990) oil-water-air 51 814 7.48 flow patterns, gas void fraction, frictional pressure drops 6 Woods et al [18] (1998) oil-water-air 26 829 12 flow patterns, void fraction, pressure drop 7 Spedding et al [19] (2000) oil-water-air 26 829 11 flow patterns, void fraction, pressure drop 8 Oddie et al [20]…”