20.500.12556/DKUM-87357 Analiza uporabe nanotekočin v toplotnih prenosnikih magistrsko delo Analysis of use of nanofluids in heat exchangers V magistrskem delu je obravnavana simulacija toplotnega prenosnika v krožni zanki, v katerem je nanotekočina. Nanotekočina je stabilna suspenzija majhnih delcev v nosilni tekočini. V magistrskem delu je nosilni medij voda, v kateri so nanodelci Al2O3. Simulacija se je izvedla v programskem paketu Ansys Fluent. Geometrija toplotnega prenosnika je bila narejena po toplotnem prenosniku, uporabljenem pri eksperimentu, ki sta ga izvedla Cobanoglu in Haktan Karadeniz v delu ''Effect of nanofluic thermophysical propertis on the performance prediciton of single-phase natural ciculation loops'' [1]. Za opis snovnih lastnosti nanotekočin, ki so temperaturno in koncentracijsko odvisne, se je uporabil UDF (User Defined Function). Gibanje in obnašanje nanodelcev v tekočini se je v programski paket Ansys Fluent vstavilo kot UDS (User defined Scalar). Rezultati cevi premera 4,75 mm so se primerjali z rezultati iz eksperimenta [1] pri toplotnih močeh 10, 30 in 50 W. Naknadno so se naredile simulacije za premere 3, 4, 5 in 6 mm ter pregledal se je izkoristek glede na večanje koncentracije nanodelcev. Rezultati so pokazali, da se z višanjem koncentracije nanodelcev veča izkoristek toplotnega prenosnika in manjša hitrost tekočine. The masters thesis focuses on simulating a heat exchanger in a circular loop operated by nanofluid using a Computational Fluid Dynamics software package Ansys Fluent. Nanofluid is a stable suspension of small particles in the base fluid. In the thesis, the base fluid is water containing Al2O3 nanoparticles. The geometry of the heat exchanger was designed based on the one used in the experiment conducted by Cobanoglu and H. Karadeniz in their work ''Effect of nanofluic thermophysical propertis on the performance prediciton of single-phase natural ciculation loops'' [1]. User Defined Functions (UDF) were employed to describe the material properties of nanofluids which are temperature and concentration dependent. The movement and behavior of nanoparticles in the fluid were incorporated into Fluent as User-Defined Scalars (UDS). The results for a pipe diameter of 4.75 mm were compared with the experimental results [1] at heat powers of 10, 30 and 50 W. Subsequently, simulations were conducted for diameters of 3, 4, 5, and 6 mm, examining the efficiency with increasing nanoparticle concentration. The findings indicated that the heat transfer efficiency increases with higher nanoparticle concentrations and by increasing the velocity of the fluid decreases. prenos toplote toplotni prenosniki nanodelci nanotekočine Ansys Fluent UDF UDS heat transfer heat exchangers nanoparticles nanofluid ANSYS Fluent UDF UDS true true false [A. Špiler] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2024-03-12 16:36:27 2024-04-03 09:40:52 2024-04-12 03:49:18 0000-00-00 00:00:00 2024 0 Maribor 0 Maribor 1 spletni vir (1 datoteka PDF (XII, 99f.)) 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 536.24:532.542(043.2) 192248835 MAG_Spiler_Andrej_2024.pdf MAG_Spiler_Andrej_2024.pdf 1 4A4B68CB3F77DDB45A6108717EA47356 5c1b63e3d67921a5be881867602a8673f2259686e8bb889dd87071437f64c26a b4bb04da-f109-11ee-9041-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=177788 Fakulteta za strojništvo 0 0 0