Design and optimization of a cavitating device for Congo red decolorization: Experimental investigation and CFD simulation

Abbas-Shiroodi, Zahra; Sadeghi, Mohammad-Taghi; Baradaran, Soroush

doi:10.1016/j.ultsonch.2020.105386

Cited by 29 publications

(11 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fluid flow velocity at the throat of the Venturi microchannel is 30 m/s, where liquid flows over the cavity and descents afterward towards the bottom wall of the channel, where the flow divides into the upstream and downstream flow (1). Vapor fraction α profiles for both phases are approximately uniform in both the fluid and vapor layers.…”

Section: Resultsmentioning

confidence: 99%

“…Step (1) shows the initial situation with a turbulent eddy on the right side of the observation region. Just next to the lower limit of 10% vapor region is the turbulent eddy impingement point on the shear layer.…”

Section: Resultsmentioning

confidence: 99%

“…When the pressure drops below the vapor pressure, cavitation, that is, the formation of vapor cavities within a homogeneous liquid medium occurs. The vapor structures are precarious, and they frequently collapse vigorously as they encounter an area of elevated pressure [1]. The mechanism of cavitation cloud shedding is among the most distinctive features of evolved cavitation.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Numerical Insight into the Kelvin-Helmholtz Instability Appearance in Cavitating Flow

2021

View full text Add to dashboard Cite

Recently the development of Kelvin-Helmholtz instability in cavitating flow in Venturi microchannels was discovered. Its importance is not negligible, as it destabilizes the shear layer and promotes instabilities and turbulent eddies formation in the vapor region, having low density and momentum. In the present paper, we give a very brief summary of the experimental findings and in the following, we use a computational fluid dynamics (CFD) study to peek deeper into the onset of the Kelvin-Helmholtz instability and its effect on the dynamics of the cavitation cloud shedding. Finally, it is shown that Kelvin-Helmholtz instability is beside the re-entrant jet and the condensation shock wave the third mechanism of cavitation cloud shedding in Venturi microchannels. The shedding process is quasi-periodic.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Numerical Insight into the Kelvin-Helmholtz Instability Appearance in Cavitating Flow

2021

View full text Add to dashboard Cite

show abstract

“…The pressure-based transient mixture multiphase approach, which resolves one set of unsteady Reynolds averaged Navier–Stokes equations using the finite volume method, was applied to describe the hydrodynamic characteristics of different Venturi designs. The standard k –ϵ turbulence model that was validated in many gas–liquid two-phase flows in a cavitation tube − is selected to describe the turbulent characteristics within the tube.…”

Section: Methodsmentioning

confidence: 99%

Machine Learning-Assisted Optimization of Microbubble-Enhanced Cold Plasma Activation for Water Treatment

Gao,

Saedi,

Shi

et al. 2024

ACS EST Water

View full text Add to dashboard Cite

Cold plasma is a powerful and eco-friendly technology with potential applications in wastewater treatment, disinfection, and sustainable agriculture. Reactive species produced by the cold plasma discharge can effectively degrade a variety of pollutants. This work focuses on microbubble-enhanced cold plasma activation (MB-CPA) through a self-suction mechanism for water treatment in a flow system. Microbubbles form under the strong turbulence at the throat of a cavitation tube, transferring active species generated from air plasma discharge into the water stream. The degradation rate of a model antibiotic compound, sulfathiazole, is compared by varying the dimensions of the cavitation tube, the flow rate of water, and the distance between the plasma discharge and the flow surface. The width of the air inlet of the cavitation tube is found to be the most important parameter for activation efficiency. Three-dimensional computational fluid dynamics simulations reveal that a higher air volume fraction and more bubbles are created with a wider air inlet. The proxy models generated by using multiple linear regression and an artificial neural network can predict degradation efficiency in good agreement with the experimental data. The optimized portable MB-CPA has the potential for broad applications in wastewater treatment, sustainable agriculture, and environmental remediation.

show abstract

“…Looking at some recent examples of utilizing CFD [12] , [13] , [14] , [15] , [16] , [17] , [18] , [19] , [20] to interpret the results and facilitate the optimization process reveals that on one side researchers approach the modeling of very complex geometries (rotor–stator interaction, narrow gaps, high-frequency oscillations, swirls), but on the other employ a very rudimentary modeling approach (steady flow approach, very basic turbulence modeling, and even assuming laminar flow conditions and no cavitation modeling). Furthermore, rarely studies of mesh independence and convergence criteria are included in the manuscript, and all too often the boundary conditions are not detailed enough.…”

Section: Introductionmentioning

confidence: 99%

Challenges of numerical simulations of cavitation reactors for water treatment – An example of flow simulation inside a cavitating microchannel

Pipp

Hočevar

Dular

2021

Ultrasonics Sonochemistry

View full text Add to dashboard Cite

Highlights Researchers with non-engineering background treat CFD too simplistic. Poor CFD approach often leads to misinterpretations and poor engineering. Cavitation exhibits complex flow features even in the very simplest geometry. A detailed example of numerical simulation of cavitation is shown. Guidelines for non CFD experts on cavitation modelling are given.

show abstract

Design and optimization of a cavitating device for Congo red decolorization: Experimental investigation and CFD simulation

Cited by 29 publications

References 39 publications

Numerical Insight into the Kelvin-Helmholtz Instability Appearance in Cavitating Flow

Numerical Insight into the Kelvin-Helmholtz Instability Appearance in Cavitating Flow

Machine Learning-Assisted Optimization of Microbubble-Enhanced Cold Plasma Activation for Water Treatment

Challenges of numerical simulations of cavitation reactors for water treatment – An example of flow simulation inside a cavitating microchannel

Contact Info

Product

Resources

About