| | SLO | ENG | Cookies and privacy

Bigger font | Smaller font
First page > Show document

Show document Help

Title:NUMERIČNO MODELIRANJE TOKA MIKROPOLARNIH TEKOČIN Z METODO ROBNIH ELEMENTOV
Authors:ID Zadravec, Matej (Author)
ID Hriberšek, Matjaž (Mentor) More about this mentor... New window
ID Škerget, Leopold (Comentor)
Files:.pdf DR_Zadravec_Matej_2009.pdf (3,55 MB)
MD5: 487822C22266E89900C7DBA7A96355F2
PID: 20.500.12556/dkum/91d20c82-3f65-41f6-8de0-0c9b084c40fe
 
Language:Slovenian
Work type:Dissertation
Organization:FS - Faculty of Mechanical Engineering
Abstract:V delu je predstavljen nov pristop k numeričnemu modeliranju tokov mikropolarnih tekočin z metodo robnih elementov. Sama teorija mikropolarnih tekočin zajema določene reološko kompleksne tekočine, pri katerih je prisoten še mehanizem rotacije notranjih struktur toka tekočine, kar ni zajeto v klasičnem sistemu Navier-Stokesovih enačb. V nalogi je predstavljeno reševanje toka tekočine s pomočjo teorije mikropolarnih tekočin, izvedeno z vključitvijo dodatnih členov v prenosno enačbo gibalne količine in reševanjem dodatne prenosne enačbe za mikrorotacijo v okviru sistema enačb, zapisanih v hitrostno vrtinčni formulaciji. Predstavljena je izpeljava vodilnih enačb, od začetnih zakonov ohranitve, zapisanih v obliki parcialno diferencalnih enačb, do integralske in na koncu diskretizirane oblike enačb za reševanje toka mikropolarnih tekočin z metodo robnih elementov. Sledi predstavitev numeričnega algoritma reševanja diskretiziranih enačb. Izpeljani algoritem, temelječ na že obstoječem algoritmu reševanja tokov z uporabo klasičnih Navier-Stokesovih enačb, je preizkušen na primerih naravne konvekcije v kotanji, prisilne konvekcije toka tekočine v kanalu ter primeru mešane konvekcije v kotanji z izvorom toplote. Primerjava rezultatov, dobljenih s pomočjo novo razvitega numeričnega algoritma, z referenčnimi rezultati drugih avtorjev, kaže na uspešnost vključitve teorije mikropolarnih tekočin v numerični algoritem na osnovi metode robnih elementov za reševanje toka tekočine s pomočjo klasične teorije Navier-Stokesovih enačb. Teoretične izpeljave in numerične simulacije podrobno obravnavajo izvor in pomen novih modelnih parametrov, ki jih vpeljemo v teoriji mikropolarnih tekočin. Rezultati izvedenih numeričnih simulacij kažejo na pomembno občutljivost tokovnega kot tudi temperaturnega polja na različne vplivne parametre mikropolarnih tekočin. Izpeljani numerični algoritem tako pomembno širi uporabnost metod računalniške dinamike tekočin na osnovi metode robnih elementov tudi na področje numerične simulacije toka mikropolarnih tekočin.
Keywords:Mikropolarne tekočine, robno območna integralska metoda, metoda robnih elementov, hitrostno vrtinčna formulacija, naravna konvekcija, tok v kanalu, mešana konvekcija.
Place of publishing:Maribor
Publisher:M. Zadravec]
Year of publishing:2009
PID:20.500.12556/DKUM-10085 New window
UDC:519.87:532.543:519.64(043.3)
COBISS.SI-ID:245242112 New window
NUK URN:URN:SI:UM:DK:GJ3S4DQU
Publication date in DKUM:06.04.2009
Views:4545
Downloads:530
Metadata:XML DC-XML DC-RDF
Categories:KTFMB - FS
:
ZADRAVEC, Matej, 2009, NUMERIČNO MODELIRANJE TOKA MIKROPOLARNIH TEKOČIN Z METODO ROBNIH ELEMENTOV [online]. Doctoral dissertation. Maribor : M. Zadravec. [Accessed 1 April 2025]. Retrieved from: https://dk.um.si/IzpisGradiva.php?lang=eng&id=10085
Copy citation
  
Average score:
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
(0 votes)
Your score:Voting is allowed only for logged in users.
Share:Bookmark and Share


Hover the mouse pointer over a document title to show the abstract or click on the title to get all document metadata.

Secondary language

Language:English
Title:NUMERICAL MODELLING OF MICROPOLAR FLUID FLOW WITH BOUNDARY ELEMENT METHOD
Abstract:In this work the new approach for numerical modeling of a micropolar fluid flow based on a boundary element method is presented. Micropolar fluid flow theory is describing flow of a rheological very complex fluids with structures, which have own rotation. Such a physical behaviour of a fluid is not included in the classical system of Navier-Stokes equations. To simulate micropolar fluid flow with the existing boundary element method based code, additional terms have to be included in the vorticity transport equation together with additional transport equation for microrotation, closing the set of governing equation, written in velocity vorticity formulation. In this work the governing equations of micropolar fluid are derived in differential, integral and discretised form, resulting from the application of the boundary element method. In deriving the numerical algorithm, the domain terms are discretised by means of subdomain technique. The derived numerical algorithm, which presents extension of existing numerical algorithm based on the classical Navier-Stokes equations, is verified through the examples of natural convection in a cavity, flow in a channel and mixed convection of micropolar fluid in a cavity. Computational results for micropolar fluids, obtained by the new numerical algorithm, show good agreement with results of other authors, confirmaing successful implementation of micropolar fluid flow theory into existing boundary element method based numerical algorithm for numerical modeling of flows with use of classical theory of Navier-Stokes equations. Through the work the meaning and importance of new model parameters included in the micropolar fluid flow theory is discused. The results of performed numerical simulations of the micropolar fluid flow show that one can expect significant sensitivity of flow and temperature fields on different micropolar fluid flow parameters. The derived numerical algorithm presents extension of the use of computational fluid dynamics methods based on boundary element method to the field of numerical simulations of micropolar fluids.
Keywords:Micropolar fluids, boundary domain integral method, boundary element method, velocity vorticity formulation, natural convection, flow in a channel, mixed convection.


Comments

Leave comment

You must log in to leave a comment.

Comments (0)
0 - 0 / 0
 
There are no comments!

Back
Logos of partners University of Maribor University of Ljubljana University of Primorska University of Nova Gorica