Numerička simulacija međudjelovanja fluida i stijenke kod disekcije aorte

master's thesis

• Title (english): Numerical fluid-solid interaction simulation of aortic dissection
• Author: Jurica Kus
• Mentor: Igor Karšaj (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2021-05-13, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

Tema ovoga rada bila je napraviti dvije numeričke simulacije međudjelovanja fluida i stijenke
(eng. fluid structure interaction, skraćeno FSI) za dvije idealizirane geometrije disekcije silazne
aorte, te pokazati numeričke karakteristike problema promatrajući oscilacije i vremenske
konvergencije fizioloških podataka od interesa. Rezultati FSI simulacije, u kojoj je primjenjena
metoda konačnih volumena (MKV), kako na domeni fluida tako i na domeni stijenke,
provjereni su metodom konačnih elemenata (MKE) na domeni stijenke za vremenske trenutke
od interesa.
U radu su kratko opisane medicinske teorijske osnove vezane za komponente i funkcije
krvožilnog sustava čovjeka, sa naglaskom na aroti i disekciji aorte, te matematički i numerički
modeli čvrstog tijela i fluida koji su korišteni za opis ponašanja stijenke i strujanja krvi. Opisana
je FSI metoda korištena za rješavanje problema međudjelovanja fluida i stijenke. Postavke
numeričkih simulacija opisane su prikazom geometrije modela, zadanih rubnih uvjeta i
računskih mreža. U zadnjem dijelu rada prikazani su rezultati numeričkih simulacija za obje
idealizirane geometrije, te je pokazana konvergencija praćenih fizikalnih veličina, usporedba
protoka FSI i CFD simulacije, te usporedba rezultata pomaka stijenke dobivenih FSI
simulacijom i analizom metodom konačnih elemenata.
Numerička simulacija međudjelovanja fluida i stijenke provedena je u open source
programskom paketu OpenFOAM v1912, koristeći eksternu biblioteku solids4foam. Provjera
rezultata na domeni stijenke provedena je pomoću komercijalnog programskog paketa
metodom konačnih elemenata.

Abstract (english)

In this work, two numerical simulations of fluid-structure interaction (FSI) are made for two
idealized geometries of descending aortic dissection. Numerical characteristics of the problem
are shown by observing oscillations and temporal convergences of physiological data of
interest, such as pressure, flow velocities, displacements and similar. The results of FSI
simulations, in which the finite volume method (FVM) was applied both in the fluid domain
and in the solid domain, were checked by the finite element method (FEM) on the solid domain
for times of interest.
The first part of this work describes the basics of medical theory related to the components and
functions of the human cardiovascular system with emphasis on the arota and aortic dissection,
and also mathematical and numerical models of solid and fluid mechanics used in this work.
The FSI method for solving the problem of fluid-structure interaction is also presented and
described, as well as setup of numerical simulations by describing the geometry of the models,
used boundary conditions and computational meshes. The results of numerical simulations for
both idealized geometry are presented in the last part of this work. The convergence of the
monitored physiological data is shown, as well as the comparison of FSI and CFD simulation
flow rates and the comparison of the results of solid displacements obtained by FSI simulation
and the analysis using finite element method.
Numerical simulation of fluid-structure interaction was performed in the open source software
OpenFOAM v1912, using the external library solids4foam. Verification of results on solid
domain was performed in the comercial software package using finite element method.

• Keywords: disekcija aorte; međudjelovanje fluida i stijenke; FSI; metoda konačnih volumena; strujanje krvi
• Keywords (english): aortic dissection; fluid-solid interaction; FSI; finite volume method; blood flow
• Language: croatian
• URN:NBN: urn:nbn:hr:235:578570
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-05-06 11:27:12