20.500.12556/DKUM-61939 Numerična simulacija kavitacijskega toka skozi divergentno radialno rego Numerical simulation of cavitating flow through radial divergent section Kavitacija je pojav prehoda kapljevine v parno fazo in nazaj v kapljevino do katerega pride pri nenadnem padcu tlaka. Pozitivne učinke kavitacije s pridom izkoriščajo v medicini med tem ko imajo njeni negativni učinki vpliv na obratovanje turbinskih in drugih strojev. Verjetno najbolj pogost negativen učinek kavitacije je kavitacijska erozija, ki nastane zaradi implozije kavitacijskih mehurčkov v bližini trdne površine. V diplomskem delu smo z uporabo programa računalniške dinamike tekočin ANSYS CFX preučili natančnost treh različnih kavitacijskih modelov. Kavitacijski modeli so bili testirani na primeru toka vode skozi divergentno radialno rego. Rezultati numeričnih simulacij so bili primerjani z rezultati meritev opravljenimi na Univerzi v Grenoblu. Izvedli smo časovno neodvisne simulacije z vsemi tremi kavitacijskimi modeli ter eno časovno odvisno simulacijo z uporabo Zwartovega kavitacijskega modela. Na podlagi dobljenih rezultatov smo zaključili, da vsi uporabljeni kavitacijski modeli pravilno napovejo področje nastanka parne faze. Cavitation is a phenomenon of liquid transition to the vapor and back to liquid. It occurs at sudden drop in pressure. The positive effects of cavitation are commonly used in medicine while its negative effects impact on the operations of turbine and other machinery. Probable the most common negative effect of cavitation is the cavitation erosion caused by the implosion of vapor bubbles near a solid surface. The thesis discusses about the accuracy of three different mass transfer models for prediction of cavitation which were tested numerically using ANSYS CFX simulation program. They were tested on the model of divergent radial test section. The results of numerical simulations were compared with the results of experimental measurements performed at the University of Grenoble. In the thesis we performed out steady simulations using all three mass transfer models. We also performed out transient simulation using Zwart model. Based on the presented results we concluded that all mass transfer models correctly predict the area of cavitation formation. Kavitacija kavitacijska erozija numerična simulacija računalniška dinamika tekočin Cavitation cavitation erosion numerical simulation computational fluid dynamics true true false [N. Mišković] Slovenski jezik Angleški jezik Diplomsko delo 2016-08-19 10:53:10 2016-09-28 12:48:15 2022-06-28 03:06:59 2019-07-11 12:38:16 2016 0 Maribor 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 004.94:532.528(043.2) 20308502 URN:SI:UM:DK:ZZN5FA4Y UN_Miskovic_Nikola_2016.pdf UN_Miskovic_Nikola_2016.pdf 1 00B7ADD6E7CAB5351E112FCA765B7D6E e1d3034aba295ff55fd79b02d4a1a1cb994d1a192cb39e40ed99f237672a9399 ab46f500-7c0d-11eb-bb7a-00155d0001ca https://dk.um.si/Dokument.php?lang=slv&id=106564 Fakulteta za strojništvo 0 0 0