Horizontal two-phase flow pattern recognition

Abstract

In the present work a Wire Mesh Sensor (WMS) has been adopted to characterize the air-water two-phase flow in a test section consisting of a horizontal Plexiglas pipe of internal diameter 19.5 mm and total length of about 6 m. The flow quality ranges from 0 to 0.73 and the superficial velocity ranges from 0.145 to 31.94 m/s for air and from 0.019 to 2.62 m/s for water. The observed flow patterns are stratified-bubble-slug/plugannular. The WMS consists of two planes of parallel wire grids (16x16) that are placed across the channel at 1.5 mm and span over the measuring cross section. The wires of both planes cross under an angle of 90°, with a diameter D wire of 70 μm and a pitch equal to 1.3 mm. The void fraction profiles are derived from the sensor data and their evolution in time and space is analyzed and discussed. The dependence of the signals on the measured fluid dynamic quantities is discussed too. The main task is to predict which flow pattern will exist under any set of operating conditions as well as to predict the value of characteristic flow parameters.

On the nature of flow patterns and pressure drop fluctuations during flow boiling

“…The results also indicated that heat transfer coefficient increased with increasing predominant frequency. Many other authors reported further important results related to the analysis of frequencies present in pressure and flow pattern fluctuations (Lee et al (2018), O'Neil et al (2018, Ma et al (2018), Monni et al (2014)).…”

Prediction of Gas–Liquid Two-phase Flow Rates through a Vertical Pipe Based on Thermal Diffusion

“…The complexity of multiphase flow originates from its variable and fluctuating phase interface, , and the conservation of dynamics at the phase interface leads to changes in the flow structure in time and space. The oil–gas–water flow, which is a kind of gas–liquid–liquid three-phase flow, can also be considered as a special type of gas–liquid two-phase flow .…”

Local characteristic of horizontal air–water two-phase flow by wire-mesh sensor

“…In recent years, the research focused on two-phase flow with the WMS technique has been growing (Assima et al, 2015; Kanai et al, 2012; Puchtler et al, 2015; Vieira et al, 2014b; Zhang et al, 2013). As a multi-points measurement technique, WMS not only measures and visualizes local and cross-sectional flow parameters (Abdulahi and Azzopardi, 2014; Barnea et al, 2013; Petritsch et al, 1997), but can also be used for flow process characterization and flow pattern recognition (Monni et al, 2014).…”