20.500.12556/RUL-151950 Numerično modeliranje srčnožilnega sistema s sklapljanjem 0D modela z 2D modelom Numerical modeling of the cardiovascular system by coupling a 0D model with a 2D model Matematično modeliranje človeškega srčnožilnega (SŽ) sistema predstavlja dobrodošlo alternativo za vpogled v odziv raznih žil, ki bi bil sicer na neinvaziven način zelo težko izvedljiv. V delu je obravnavan odziv SŽ sistema na aplikacijo negativnega tlaka na spodnjem delu telesa (ang. Lower Body Negative Pressure – LBNP). LBNP se uporablja kot protiukrep za zmanjševanje negativnih vplivov na SŽ sistem, ki so posledica izpostavljenosti mikrogravitaciji (npr. pri potovanju v vesolje). Kljub temu da je LBNP predmet raziskav že desetletja, njegov vpliv na SŽ sistem še ni docela znan. Raziskava se osredotoča na določitev hemodinamskega odziva jugularne vene (JV) pri različnih vrednostih LBNP. Za potrebe analize je bilo razvito numerično orodje, tj. večdimenzionalni model, ki združuje zaprtozančni 0D hemodinamski model z osno simetričnim 2D modelom. Tako 0D kot 2D model temeljita na realnih, eksperimentalno pridobljenih podatkih. Tak pristop omogoča razumevanje globalnih hemodinamskih interakcij (0D model) kot tudi vpogled v lokalne tokovne razmere (2D model). S pomočjo sklopljenega modela je bil nato določen in analiziran vpliv LBNP na tokovne razmere v JV, kar v literaturi do sedaj še ni bilo pokazano. Mathematical modelling of the human cardiovascular (CV) system represents a welcome alternative to gain insight into the response of various blood vessels, which would be otherwise very difficult to achieve in a non-invasive way. In the present work, the response of the CV system to the application of lower body negative pressure (LBNP) is studied. LBNP is used as a countermeasure to reduce the negative effects on the CV system resulting from exposure to microgravity (e.g., during space flight). Although LBNP has been subject of research for decades, its impact on the CV system remains not fully understood. The focus of the present study is to determine the hemodynamic response of the jugular vein (JV) at different values of LBNP. For the purpose of the analysis, a numerical tool was developed, i.e., a multidimensional model combining a closed-loop 0D hemodynamic model with an axisymmetric 2D model. Both the 0D and 2D models are based on real, experimentally obtained data. Such an approach enables an understanding of global hemodynamic interactions (0D model) as well as insights into local flow conditions (2D model). The coupled model was then used to determine and analyse the influence of LBNP on the JV flow conditions, which has not been demonstrated in the literature so far. hemodinamika srčnožilni sistem sklapljanje večdimenzionalnih modelov zaprtozančni 0D modeli električno-hidravlična analogija LBNP tokovne razmere v žilah hemodynamics cardiovascular system coupling of multidimensional models lumped-parameter models electric-hydraulic analogy LBNP blood flow conditions true false false [D. Gnidovec] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2023-10-26 08:30:38 2023-10-26 08:30:41 2023-11-15 10:11:45 0000-00-00 00:00:00 2023 0 0 XXIV, 96 str. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 004.942:519.876.5:611.1(043.2) 257789 172213507 32414.pdf 32414.pdf 1 9B84C2AC4FD3E53870593B70983A2354 022ae47c75d9e002e60aca0d0777a36368ffb45f02b400350a9c863427f162ac 2f5d704c-73c9-11ee-a653-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=177111 Fakulteta za strojništvo 0 0 0