A Fluid Dynamic Study in a Rotating Disk Applied in Granulation of Fertilizers

In fertilizers industries the granulation is an essential operation to form pellets with good quality. The granular product has improved handling, hardness, solubility, resistance to segregation and meets requirements such as the size, shape and particle size distribution through appropriate manipulation of the process variables. There are several types of granulators, however, this work is intended to study a granulator known as rotating disk, which promotes agitation of the particles by rotating around its axis. Although these devices are used industrially, cannot be found in the literature many details about the fluid dynamics in these operations. To study the fluid dynamics behavior of these particles on a rotation disk was analyzed the variables: rotation axis and filling degree. It was verified the existence of flow regimes which depends on these variables: rolling, cascading and centrifugation. Also, it was evaluated the dynamic angle of repose, that characterizes the rolling regime. This work aimed to obtain results of fluid dynamics that describe the behavior of solids flowing in a rotating disk. Thus, to meet the objectives of this work, simulations was carried out through the techniques of Computational Fluid Dynamics (CFD) and Discrete Element (DEM) to evaluate different parameter values: restitution coefficient (η), friction coefficient (μ) and the coefficient of elasticity (k) of the linear model "spring-dashpot" to find a good set of parameters that characterizes this system.

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Analisis Distribusi Temperatur dan Aliran Fluida pada Proses Pengeringan Butiran Teh Bentuk Silinder Di Dalam Fluidized Bed Dryer Menggunakan Computational Fluid Dynamic (CFD)

ROTASI ◽

10.14710/rotasi.20.4.237-243 ◽

2019 ◽

Vol 20 (4) ◽

pp. 237

Author(s):

MSK Tony Suryo Utomo ◽

Eflita Yohana ◽

Mauli Astuti Khoiriyah

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Fluidized Bed ◽

Computational Fluid Dynamic ◽

Fluid Dynamic ◽

Fluidized Bed Dryer ◽

Computational Fluid Dynamics Cfd

Pengeringan merupakan proses perpindahan panas dan uap air secara simultan yang memerlukan energi panas untuk menguapkan kandungan air dari bahan yang akan dikeringkan. Penelitian ini dilakukan dengan cara simulasi. Produk yang dipilih untuk simulasi ini yaitu teh. Simulasi numerik perpindahan massa pada teh dilakukan dengan menempatkan material teh pada domain komputasi sebuah aliran eksternal. Penelitian ini bertujuan untuk menganalisis distribusi temperatur pada partikel teh dengan menggunakan Computational Fluid Dynamics (CFD) dan menganalisis pengaruh variasi kecepatan inlet dan temperatur inlet terhadap waktu pengeringan sehingga diperoleh metode pengeringan yang paling optimum pada pengeringan teh. Penurunan massa pada teh dihitung secara analitik dengan menggunakan persamaan laju penurunan massa. Teh dimodelkan dengan bentuk menyerupai silinder setelah dilakukan pelayuan untuk kemudian dikeringkan. Kecepatan masuk aliran udara dan temperatur masuk divariasikan sesuai dengan batas kecepatan minimum dan maksimum fluidisasi dan temperatur pengeringan teh untuk fluidized bed dryer. Waktu yang digunakan untuk menurunkan kadar air hingga 3% berdasarkan temperatur pada kecepatan 1,6 m/s secara berurutan adalah 354 s (880C), 300 s (930C), dan 256 s (980C). Sementara pada kecepatan 2,6 m/s waktu yag dibutuhkan adalah 277 s (880C), 234 s (930C), dan 200 s (980C) serta untuk kecepatan 3,6 m/s berturut-turut 235 s (880C), 199 s (930C), dan 169 s (980C). Untuk pengeringan teh lebih optimal dilakukan dengan menaikkan kececepatan masuk aliran fluida dibandingkan dengan menaikkan temperatur.

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Computational fluid dynamic prediction of the residence time of a vortex separator applied to disinfection

Water Science & Technology ◽

10.2166/wst.2005.0058 ◽

2005 ◽

Vol 52 (3) ◽

pp. 29-36 ◽

Cited By ~ 2

Author(s):

D. Egarr ◽

M.G. Faram ◽

T. O'Doherty ◽

D. Phipps ◽

N. Syred

Keyword(s):

Fluid Dynamics ◽

Residence Time ◽

Air Conditioning ◽

Fluid Dynamic ◽

Dynamic Prediction ◽

Disinfection Process ◽

Computational Fluid Dynamics Cfd ◽

Vortex Separator ◽

The Mean ◽

Computational Fluid Dynamic Prediction

A Hydrodynamic Vortex Separator (HDVS) has been modelled using Computational Fluid Dynamics (CFD) in order to predict the residence time of the fluid at the overflow and underflow outlets. A technique which was developed for use in Heating, Ventilation and Air Conditioning (HVAC) was used to determine the residence time and the results have been compared with those determined experimentally. It is shown that in using CFD, it is possible to predict the mean residence time of the fluid and to study the response to a pulse injection of tracer. It is also shown that it is possible to apply these techniques to predict the mean survival rate of bacteria in a combined separation and disinfection process.

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Computational fluid dynamic analysis reveals the underlying physical forces playing a role in 3D multiplex brain organoid cultures

10.1101/369082 ◽

2018 ◽

Author(s):

Livia Goto-Silva ◽

Nadia M. E. Ayad ◽

Iasmin L. Herzog ◽

Nilton P. Silva ◽

Bernard Lamien ◽

...

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Shear Stress ◽

Suspension Culture ◽

Fluid Dynamic ◽

Spinner Flask ◽

List Type ◽

Computational Fluid Dynamic Analysis ◽

Computational Fluid Dynamics Cfd ◽

Brain Organoid

AbstractOrganoid cultivation in suspension culture requires agitation at low shear stress to allow for nutrient diffusion, which preserves tissue structure. Multiplex systems for organoid cultivation have been proposed, but whether they meet similar shear stress parameters as the regularly used spinner flask and its correlation with the successful generation of brain organoids, has not been determined. Herein, we used computational fluid dynamics (CFD) analysis to compare two multiplex culture conditions: steering plates on an orbital shaker and the use of a previously described bioreactor. The bioreactor had low speed and high shear stress regions that may affect cell aggregate growth, depending on volume, whereas the CFD parameters of the steering plates were closest to the parameters of the spinning flask. Our protocol improves the initial steps of the standard brain organoid formation, and organoids produced therefrom displayed regionalized brain structures, including retinal pigmented cells. Overall, we conclude that suspension culture on orbital steering plates is a cost-effective practical alternative to previously described platforms for the cultivation of brain organoids for research and multiplex testing.HighlightsImprovements to organoid preparation protocolMultiplex suspension culture protocol successfully generate brain organoidsComputational fluid dynamics (CFD) reveals emerging properties of suspension culturesCFD of steering plates is equivalent to that of spinner flask cultures

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Some Aspects of Uncertainty in Computational Fluid Dynamics Results

Journal of Fluids Engineering ◽

10.1115/1.2926512 ◽

1991 ◽

Vol 113 (4) ◽

pp. 538-543 ◽

Cited By ~ 42

Author(s):

U. B. Mehta

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Sensitivity Analysis ◽

Uncertainty Analysis ◽

Dynamic Systems ◽

Fluid Dynamic ◽

Practical Method ◽

Computational Fluid Dynamics Cfd

Uncertainties are inherent in computational fluid dynamics (CFD). These uncertainties need to be systematically addressed and managed. Sources of these uncertainties are identified and some aspects of uncertainty analysis are discussed. Some recommendations are made for quantification of CFD uncertainties. A practical method of uncertainty analysis is based on sensitivity analysis. When CFD is used to design fluid dynamic systems, sensitivity-uncertainty analysis is essential.

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Comparing different CFD software with NACA 2412 airfoil

Progress in Agricultural Engineering Sciences ◽

10.1556/446.2020.00004 ◽

2020 ◽

Author(s):

Csaba Hetyei ◽

Ildikó Molnár ◽

Ferenc Szlivka

Keyword(s):

Fluid Dynamics ◽

Numerical Simulation ◽

Fluid Dynamic ◽

Aerospace Industry ◽

Measured Data ◽

Theoretical Knowledge ◽

Dynamic Simulations ◽

Computational Fluid Dynamics Cfd ◽

The Difference ◽

Volume Method

AbstractThe engineering application's design process starts with a concept, based on our theoretical knowledge and continues with a numerical simulation. In our paper, we review the finite volume method (FVM) which is used generally for heat and fluid dynamic simulations.We compare three different computational fluid dynamics (CFD) software (based in the fine volume method) for validating a NACA airfoil, which can be used for example in the aerospace industry for an airplane's wing profile, and it can be used for example in the renewable industry for a wind turbine's blade or a water turbine's impeller profile. At the end of this paper, the result of our simulations will be compared with a validation case and the difference between the CFD software and the measured data will be presented.

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