A Critical Review of Advanced Experimental Techniques to Measure Two-Phase Gas/Liquid Flow

Rahman, Mohammad Azizur; Heidrick, T. R.; Fleck, Brian A.

doi:10.2174/1876973x00902010054

Cited by 11 publications

(5 citation statements)

References 111 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, it is always challenging to obtain accurate information about the flow, such as fluid/gas velocity, film thickness, droplet entrainment, drop size, drop velocity, void fraction, disturbance waves, etc. Some experimental techniques used to measure the void fraction and flow regime [11], and film thickness [12,13] have been summarized. The following section summarises and evaluates the experimental techniques used in previous research, focusing on the flow regime, annular thin film and entrained droplets, followed by a summary of the numerical investigations in the field.…”

Section: Investigation Methodologiesmentioning

confidence: 99%

Two-Phase Annular Flow in Vertical Pipes: A Critical Review of Current Research Techniques and Progress

Xue¹,

Stewart

Kelly

et al. 2022

Water

View full text Add to dashboard Cite

Two-phase annular flow in vertical pipes is one of the most common and important flow regimes in fluid mechanics, particularly in the field of building drainage systems where discharges to the vertical pipe are random and the flow is unsteady. With the development of experimental techniques and analytical methods, the understanding of the fundamental mechanism of the annular two-phase flow has been significantly advanced, such as liquid film development, evolution of the disturbance wave, and droplet entrainment mechanism. Despite the hundreds of papers published so far, the mechanism of annular flow remains incompletely understood. Therefore, this paper summarizes the research on two-phase annular flow in vertical pipes mainly in the last two decades. The review is mainly divided into two parts, i.e., the investigation methodologies and the advancement of knowledge. Different experimental techniques and numerical simulations are compared to highlight their advantages and challenges. Advanced underpinning physics of the mechanism is summarized in several groups including the wavy liquid film, droplet behaviour, entrainment and void fraction. Challenges and recommendations are summarized based on the literature cited in this review.

show abstract

Section: Investigation Methodologiesmentioning

confidence: 99%

Two-Phase Annular Flow in Vertical Pipes: A Critical Review of Current Research Techniques and Progress

Xue¹,

Stewart

Kelly

et al. 2022

Water

View full text Add to dashboard Cite

show abstract

“…In the past decades, more advanced measurement techniques have been introduced that are able to provide higher resolution experimental data on void fraction distributions (Rahman et al, 2009). Experimental data from high-speed cameras, high-speed X-ray radiography, and wire-mesh sensor can provide the additional resolution for a more extensive validation of CFD models.…”

Section: Introductionmentioning

confidence: 99%

CFD Simulation of Two-Phase Flows in Helical Coils

et al. 2020

View full text Add to dashboard Cite

The behavior of two-phase flow and corresponding flow regimes in helical tubes significantly differ when compared to two-phase flows in straight tubes due to centrifugal and torsion effects. In order to gain physical insight and gather data for validating computational models, a large number of experiments were performed on a helical coil experimental setup operated with a mixture of water and air. The experimental data were used to assess the predictive capabilities of current two-phase Computational Fluid Dynamics (CFD) models based on the Volume of Fluid (VOF) approach. In the present paper, a comparison of the CFD simulation results with the high-resolution experimental data is discussed, with special emphasis on two-phase pressure drops and void fraction distributions. It is shown that the CFD VOF model is able to correctly capture the occurrence of five flow regimes observed in the experiments, namely bubbly flow, plug flow, slug flow, slug-annular flow, and annular flow. However, a good quantitative agreement for pressure drops and void fraction distributions is found in slug flow and slug-annular flow regimes only. The good agreement found only in a limited range of flow regimes demonstrates that there is not a single set of best-practice guidelines for CFD VOF models that can be applied across a wide range of two-phase flow regimes. Also, there is not a single mesh that can be used to simulate all of the flow regimes and a case-specific mesh and time-step convergence study is needed for each individual flow regime. In the current study, optimal mesh size and time step were obtained for a slug flow test case. Hence, good agreement was obtained only for similar flow regimes, leading to significant disagreement with experimental data for test cases with substantially different flow patterns.

show abstract

“…Flow induced vibration is an important issue that affects the reliability of structures in industries. Significant cases of wears and failures in these structures have been reported under single and two-phase flow conditions [1], [2]. Unlike single phase flow, two-phase flow is of concern because of the flow unsteadiness.…”

Section: Introductionmentioning

confidence: 99%

Flow Induced Vibration of Separated Two-Phase Flow Due to Restricting Orifice

Bamidele¹,

Ahmed²,

Hassan³

2019

International Conference on Fluid Flow, Heat and Mass Transfer

View full text Add to dashboard Cite

The current work investigates flow-induced vibrations of piping structures with flow restricting orifices due to separated two-phase flow. Air-water flow through a flow restricting orifice with area ratio of 0.25 was experimentally investigated at various superficial velocities ranging from JL from 0.46 m/s to 1.3 m/s and JG from 0.76 m/s to 1.7 m/s. The vibration response of the piping structure was captured for stratified-wavy and dispersed annular flow patterns. Also, the time signals of piping displacement and void fraction with the flow structure were analysed. The results show that Flow induced vibrations of piping structures with a flow restricting orifice due to separated two-phase flow due to flow restricting orifice is a strong function of the void fraction upstream of the orifice for stratified-wavy flow pattern. Moreover, the amplitude of vibration at frequency conditions in the neighbourhood of the dominant void fraction frequency reduced with the increase in the gas superficial velocity.

show abstract

A Critical Review of Advanced Experimental Techniques to Measure Two-Phase Gas/Liquid Flow

Cited by 11 publications

References 111 publications

Two-Phase Annular Flow in Vertical Pipes: A Critical Review of Current Research Techniques and Progress

Two-Phase Annular Flow in Vertical Pipes: A Critical Review of Current Research Techniques and Progress

CFD Simulation of Two-Phase Flows in Helical Coils

Flow Induced Vibration of Separated Two-Phase Flow Due to Restricting Orifice

Contact Info

Product

Resources

About