Analysis of viscous fluid flow in a pressure-swirl atomizer using large-eddy simulation

Laurila, Erkki; Roenby, Johan; Maakala, Viljami; Peltonen, Petteri; Kahila, Heikki; Vuorinen, Ville

doi:10.1016/j.ijmultiphaseflow.2018.10.008

Cited by 46 publications

(22 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The correlation predicted the film thickness with high accuracy up to pressures of 3 MPa. Other recent studies with different atomizer geometries, pressures, and liquid properties have found that the expression estimates the liquid film thickness fairly well (Laurila et al, 2019;Wimmer & Brenn, 2013).…”

Section: Introductionmentioning

confidence: 69%

Oil droplet breakup during pressure swirl atomization of food emulsions: Influence of atomization pressure and initial oil droplet size

Taboada

Schäfer

Karbstein

et al. 2020

J Food Process Engineering

View full text Add to dashboard Cite

Atomization of emulsions with pressure swirl atomizers is a common task in food process engineering. Especially in spray drying processes for food materials like dairy products, it is the technology of choice. During atomization, emulsions are subjected to high stresses, which can lead to deformation and breakup of the dispersed droplets. In this study, the influence of atomization pressure (5–20 MPa) and initial oil droplet size (0.26, 3.1, and 20.8 μm) on the oil droplet breakup during atomization of food based oil‐in‐water emulsions with pressure swirl atomizers was investigated. It was shown that a significant oil droplet breakup takes place upon atomization. The size of oil droplets with an initial value of 3.1 and 20 μm was reduced up to 0.36 μm. No breakup of oil droplets with an initial value of 0.26 μm was observed. The breakup was highly dependent on the atomization pressure. The results were analyzed based on existing knowledge on droplet breakup in laminar flow. A concept to estimate capillary numbers during atomization was developed based on common models from different applications. The results of this study can be used to control the resulting oil droplet size after atomization with pressure swirl atomizers.Practical applicationSpray drying of emulsions is a widely used process in the food industry to produce products with encapsulated oily components. Product examples include infant formula, milk powder, and the encapsulation of aroma and coloring compounds. Breakup of the oil droplets during the atomization step of spray drying can change a previously adjusted and desired oil droplet size. As the oil droplet size in the final product can be responsible for several properties like sensorial aspects and stability, a control of oil droplet breakup is essential. Pressure swirl atomizers are widely used in industrial applications as atomization devices. In this study, oil droplet breakup during atomization with these atomizers was investigated. The findings in this study allow a better control of the oil droplet size during atomization in practical applications.

show abstract

Section: Introductionmentioning

confidence: 69%

Oil droplet breakup during pressure swirl atomization of food emulsions: Influence of atomization pressure and initial oil droplet size

Taboada

Schäfer

Karbstein

et al. 2020

J Food Process Engineering

View full text Add to dashboard Cite

show abstract

“…Convection terms are discretized with a Gamma-flux limited scheme ( Jasak et al, 1999 ) while linear schemes are used for all the other terms. We utilize the implicit LES approach as a stand-alone subgrid model similar to our previous studies ( Peltonen et al, 2018 , Peltonen et al, 2019 , Laurila et al, 2019 ).…”

Section: Models Methods and Softwarementioning

confidence: 99%

Modelling aerosol transport and virus exposure with numerical simulations in relation to SARS-CoV-2 transmission by inhalation indoors

et al. 2020

View full text Add to dashboard Cite

We provide research findings on the physics of aerosol and droplet dispersion relevant to the hypothesized aerosol transmission of SARS-CoV-2 during the current pandemic. We utilize physics-based modeling at different levels of complexity, along with previous literature on coronaviruses, to investigate the possibility of airborne transmission. The previous literature, our 0D-3D simulations by various physics-based models, and theoretical calculations, indicate that the typical size range of speech and cough originated droplets ( ) allows lingering in the air for ) so that they could be inhaled. Consistent with the previous literature, numerical evidence on the rapid drying process of even large droplets, up to sizes , into droplet nuclei/aerosols is provided. Based on the literature and the public media sources, we provide evidence that the individuals, who have been tested positive on COVID-19, could have been exposed to aerosols/droplet nuclei by inhaling them in significant numbers e.g. . By 3D scale-resolving computational fluid dynamics (CFD) simulations, we give various examples on the transport and dilution of aerosols ( ) over distances in generic environments. We study susceptible and infected individuals in generic public places by Monte-Carlo modelling. The developed model takes into account the locally varying aerosol concentration levels which the susceptible accumulate via inhalation. The introduced concept, ’exposure time’ to virus containing aerosols is proposed to complement the traditional ’safety distance’ thinking. We show that the exposure time to inhale aerosols could range from to or even to depending on the situation. The Monte-Carlo simulations, along with the theory, provide clear quantitative insight to the exposure time in different public indoor environments.

show abstract

“…Recently, a geometric VOF method has also been implemented as a part of the isoAdvector [32] solver, which was used in present study. This solver reportedly offers a sharper interface tracking than the MULES [33,34].…”

Section: Methodsmentioning

confidence: 99%

Assessment of CFD Model Performance for Flows around a Hydraulic Structure of Complex Geometry

Grivalszki

Fleit

Baranya

et al. 2020

Period. Polytech. Civil Eng.

View full text Add to dashboard Cite

Computational Fluid Dynamics (CFD) modeling has become a widely used research tool in the hydraulic engineering community, however, for many problems the numerical model setup and even the selection of the suitable hydrodynamic solver is still a challenging task. This is the case for fine scale analysis of flow features around hydraulic structures of complex geometry, where generation of the 3D grid, application of the correct turbulence modeling approach, or modeling of the free surface all require extensive experience and knowledge. The aim of this paper is to perform a numerical hydrodynamic experiment for a hydraulic structure with complex geometry to assess the model performance, in terms of grid resolution, grid refinement methods as well as turbulence modeling. The open source modeling environment of OpenFOAM is tested and validated against laboratory measurements, moreover, practical recommendations are made for future applications of the numerical solver.

show abstract

Analysis of viscous fluid flow in a pressure-swirl atomizer using large-eddy simulation

Cited by 46 publications

References 51 publications

Oil droplet breakup during pressure swirl atomization of food emulsions: Influence of atomization pressure and initial oil droplet size

Oil droplet breakup during pressure swirl atomization of food emulsions: Influence of atomization pressure and initial oil droplet size

Modelling aerosol transport and virus exposure with numerical simulations in relation to SARS-CoV-2 transmission by inhalation indoors

Assessment of CFD Model Performance for Flows around a Hydraulic Structure of Complex Geometry

Contact Info

Product

Resources

About