Analiza strujanja krvi u intrakranijskoj aneurizmi

master's thesis

• Title (english): Hemodynamic analysis of intracranial aneurysm
• Author: Josip Živić
• Mentor: Igor Karšaj (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2018-07-13, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering; Precision Mechanical Engineering

Abstract

Paralelno s razvitkom računala i novih algoritama sve se više primjenjuju numeričke metode (npr. metode konačnih elemenata (MKE) i metode konačnih volumena (MKV)) u području biomehanike i mehanike bioloških strujanja. Razvojem različitih područja biomehanike postupno se olakšava pronalaženje pravih tretmana za pacijente te se uvelike pospješuje njihovo liječenje. Tema ovog diplomskog rada je analiza strujanja krvi kroz intrakranijsku aneurizmu. Intrakranijske aneurizme podrazumijevaju abnormalno patološko proširenje arterija na području mozga. Tijekom vremena stijenka žile gubi čvrstoću pod utjecajem sile tlaka te nastaje vrećasto proširenje. Potencijali problemi koje uzrokuje aneurizma su usporavanje cirkulacije i stvaranje krvnih ugrušaka dok je najopasniji ishod njena ruptura i unutarnje krvarenje koje je opasno po život. Aneurizme su najčešće asimptomatske te se najčešće otkrivaju slučajno na fizikalnom pregledu, ultrazvuku ili čak nakon smrtnog slučaja uzrokovanog rupturom aneurizme. Proračun je proveden u programskom paketu CRIMSON a analiza rezultata u programskom paketu ParaView i Python 3. Analizirani su slučajevi stacionarnog i pulsirajućeg strujanja za više različitih rubnih uvjeta. Zaključeno je da srednje vrijednosti protoka i tlaka u izlaznim presjecima dobivenim iz analize pulsirajućeg strujanja odgovaraju srednjim vrijednostima tih veličina iz stacionarne analize, kada se u stacionarnoj analizi koristi vremenski osrednjeni ulazni protok iz nestacionarne analize. Dobivena raspodjela smičnih naprezanja može poslužiti kao osnova za određivanje potencijalne opasnosti za razvoj aneurizme.

Abstract (english)

With the development of computers and new algorithms in modern age, new numerical methods ( such as finite element methods (FEM) and finite volume method (FVM)) are being used in the biomechanic science and mechanic of biological flow. By the same time with the development of biomechanics, right treatments are much easier to find so patients have better recovery chances. Master thesis theme is analysis of the blood flow through intracranial aneurysm. Intracranial aneurism is abnormal pathological expanding in the brain area. Through the time vessel wall loses its strength because of pressure force and baggy expansion is made. Slow circulation and clot formation are potential problems caused by aneurysm while its most dangerous outcome is aneurysm rupture and internal bleeding which can be lethal. Most of aneurysms are asymptomatic and they are discovered mostly by accident during the physical examinations, ultrasonic examinations or posthumously after death caused by aneurysms rupture. Calculations were made in software program CRIMSON (Cardiovascular Integrated Modelling and Simulation ) and visualizations were made in software programs Paraview and Python 3. Steady and pulsed analysis were made for several boundary conditions. It is proven that the mean values of flow and pressure in the pulsing simulation are just the same as mean values in the steady simulation when mean input flow is used as input. Obtained residual stress distribution can be used as starting point for determining potential danger of developing aneurysm.

• Keywords: Intrakranijska aneurizma; strujanje krvi; biomehanika; metoda konačnih elemenata
• Keywords (english): Intracranial aneurysm; blood flow; biomechanics; finite element method
• Language: croatian
• URN:NBN: urn:nbn:hr:235:751760
• 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: 2019-05-22 22:40:00