The effect of primary and secondary flows on the homogenization process in a vertical bladed mixer.

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985858%3A_____%2F21%3A00543766" target="_blank" >RIV/67985858:_____/21:00543766 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/44555601:13440/21:43896490 RIV/60461373:22340/21:43922741

Výsledek na webu

<a href="http://hdl.handle.net/11104/0321864" target="_blank" >http://hdl.handle.net/11104/0321864</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.powtec.2021.06.015" target="_blank" >10.1016/j.powtec.2021.06.015</a>

Jazyk výsledku

angličtina

Název v původním jazyce

The effect of primary and secondary flows on the homogenization process in a vertical bladed mixer.

Popis výsledku v původním jazyce

This article focuses on numerical simulations of the granular mixing process in a vertical cylindrical mixer with two opposed flat blades with a 45° rake angle. Computer simulations were performed by the discrete element method. The blending was examined for the blades' stirrer speeds in the range from 1.9 to 960 rpm and three different initial spatial configurations. The development of the concentration patterns and the evolution of phase interphase between different types of particles have shown that the homogenization process depends not only on the system's dynamics but also on the initial spatial distribution of particles. The dependence on the initial distribution is provided by involving primary and secondary flows in different time-scale in the homogenization process. This ability of the individual flows to engage in the mixing is granted by the mutual synergy between the direction of movements of particles located on the phase interface and the orientation of the phase interface. Because there is a significant difference between the intensity of primary and secondary flows in most cases, an improperly oriented phase interface will significantly slow down the entire rate of the homogenization process. On the other hand, during the mixing process, the phase interface expands and deforms, which gradually also allows the rest of the flows to get involved in the homogenization process. Based on the results, the basic rules have been identified for effective homogenization. As a mixing index, the relative surface of the phase interface was used. By comparing individual homogenization curves, it follows that the critical factor for the homogenization process is the centrifugal force. When it is in balance with other forces, it encourages homogenization. On the contrary, if it becomes the dominant force in the system, it causes a significant deformation of the surface, and its effect on the homogenization process is destructive.

Název v anglickém jazyce

The effect of primary and secondary flows on the homogenization process in a vertical bladed mixer.

Popis výsledku anglicky

This article focuses on numerical simulations of the granular mixing process in a vertical cylindrical mixer with two opposed flat blades with a 45° rake angle. Computer simulations were performed by the discrete element method. The blending was examined for the blades' stirrer speeds in the range from 1.9 to 960 rpm and three different initial spatial configurations. The development of the concentration patterns and the evolution of phase interphase between different types of particles have shown that the homogenization process depends not only on the system's dynamics but also on the initial spatial distribution of particles. The dependence on the initial distribution is provided by involving primary and secondary flows in different time-scale in the homogenization process. This ability of the individual flows to engage in the mixing is granted by the mutual synergy between the direction of movements of particles located on the phase interface and the orientation of the phase interface. Because there is a significant difference between the intensity of primary and secondary flows in most cases, an improperly oriented phase interface will significantly slow down the entire rate of the homogenization process. On the other hand, during the mixing process, the phase interface expands and deforms, which gradually also allows the rest of the flows to get involved in the homogenization process. Based on the results, the basic rules have been identified for effective homogenization. As a mixing index, the relative surface of the phase interface was used. By comparing individual homogenization curves, it follows that the critical factor for the homogenization process is the centrifugal force. When it is in balance with other forces, it encourages homogenization. On the contrary, if it becomes the dominant force in the system, it causes a significant deformation of the surface, and its effect on the homogenization process is destructive.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20402 - Chemical process engineering

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Powder Technology

ISSN

0032-5910

e-ISSN

1873-328X

Svazek periodika

391

Číslo periodika v rámci svazku

OCT 2021

Stát vydavatele periodika

NL - Nizozemsko

Počet stran výsledku

14

Strana od-do

253-266

Kód UT WoS článku

000678458400011

EID výsledku v databázi Scopus

2-s2.0-85108992624