http://aghajar.okstate.edu/sites/default/files/pub-pdfs/Bhagwat%20%26%20Ghajar_ETFS%2039%282012%29213-227%20-%20First%20page%20only.pdf

Similarities and differences in the flow patterns and void fraction in vertical upward and downward two phase flow

The measurement of local flow parameters for gas–liquid two-phase bubbly flows using a dual-sensor probe array

Flow regime, void fraction and interfacial area transport and characteristics of co-current downward two-phase flow

An array of dual-sensor conductance probes, which contains a number of dual-sensor probes equispaced across the diameter of an 80 mm pipe, is introduced in this paper for characterizing bubbly oil-in-water pipe flows inclined at angles from 15? to 60? to the vertical. Each dual-sensor probe measures the local axial oil velocity and the local oil volume fraction at the position of the probe. Choosing an averaging interval of 0.05 s, values of the local oil volume fraction and the local oil velocity were measured simultaneously at the different probe positions, enabling the time-dependent structure of the two-phase flow to be investigated. After data processing, time-dependent variations of volume fraction along the pipe were found which are consistent with the presence of intermittent Kelvin?Helmholtz wave structures in the flow. A high-speed dual-plane ERT system was used to measure the axial propagation speed of these Kelvin?Helmholtz waves, using cross correlation. This paper presents results for the measured characteristics of inclined oil-in-water flows including (i) time-averaged and time-dependent oil volume fraction and velocity distributions and (ii) the Kelvin?Helmholtz wave properties including the wave speed, wave amplitude, wavelength and wave frequency.

https://iopscience.iop.org/article/10.1088/0957-0233/22/10/104012/pdf

Use of a novel dual-sensor probe array and electrical resistance tomography for characterization of the mean and time-dependent properties of inclined, bubbly oil-in-water pipe flows

Experimental investigation of a vertically downward two-phase air-water slug flow

Supermultiple-point-electrode conductance probe method has recently become realistic for examining the interfacial structure in gas-liquid two-phase flow. A new instrument based on this method was developed and applied into vertical downward gas-liquid two-phase flow The graphics of interfacial profiles are presented on typical flow patterns briefly and on plug and foam flows in detail. It is pointed out that the plug flow lies in the two regions separated by the foam flow, which was newly found in this study. The interfacial profiles of gas slugs depend strongly on the slip velocity of gas slug to the liquid phase in liquid slug, and the two regions of plug flow are classified into the low and high slip velocity groups. In the former group slip velocity is mostly negative Furthermore, some findings are introduced on the prediction of the void fraction in liquid slug, on its relation with the two flow regions of plug flow, and on a characteristic property observed in the fluctuation of pressure g...

H. Shimizu

Papers

Interfacial profiles and flow characteristics in vertical downward two-phase plug and foam flows