1. Izdelava parametričnega modela Bankijeve turbine : diplomsko deloŽan Suša, 2024, undergraduate thesis Abstract: Namen zaključnega dela je izdelati generični model Bankijeve turbine v sistemu CAD. V prvem delu zaključnega dela so opisane turbine, ki se uporabljajo v velikih in malih hidroelektrarnah, in osnovne značilnosti sistema CAD. V osrednjem delu je opisan način kreiranja in povezovanja konstrukcijske tabele z vsemi parametri za modeliranje Bankijeve turbine po preračunu iz literature. Zasnovana tabela omogoča izvedbo preračuna glede na vhodne karakteristike turbine, volumski pretok in višino padca ter avtomatsko kreiranje modela turbine iz generičnega modela za izračunane parametre. Za kreiranje modela so uporabljene napredne funkcije sistema CAD.
Keywords: SolidWorks, modeliranje, generični model, Bankijeva turbina.
Published in DKUM: 20.09.2024; Views: 0; Downloads: 19
 Full text (3,42 MB) |
2. Virtualni inženiring I : komponente virtualnega inženiringa, zapiski predavanjGorazd Hren, 2024 Abstract: Zapiski predavanj so namenjeni študentom, ki se vsakodnevno in vedno bolj srečujejo z uporabo razvojnih računalniških orodij pri designu izdelkov. Izredno kakovostne in tudi kompleksnejše računalniške aplikacije omogočajo simulacije in analize inženirskih rešitev preden so te implementirane kot prototipi ali končni izdelki. Virtualni inženiring najprej tvorijo komponente za ustvarjanje geometrije, sistemi CAD in povratni inženiring s sistemi skeniranja, ki predstavlja osnovo za nadaljnje postopke razvoja izdelkov. Naslednje komponente so izdelava virtualnih prototipov v navideznem okolju ali fizičnih prototipov, katerih izdelava je dandanes večinoma izvedena s 3D tiskom. Izrednega pomena v razvoju izdelkov so numerične simulacije, ki omogočajo analize -trdnosti, dinamike tekočin in gibanja mehanizmov - glede na robne pogoje. S pridobljenimi podatki lahko načrtujemo proizvodnjo, logistiko, kontrolo kakovosti, ergonomijo, marketing, preden gre izdelek v končno izdelavo. Vse te komponente povezujejo informacijski sistemi DMU, PLM, ki omogočajo in tudi določajo organizacijsko strukturo razvojnega dela, opisanem v zadnjem poglavju: Virtualni razvoj izdelkov.
Keywords: virtualni inženiring, sistemi CAD, povratni inženiring, numerične simulacije, virtualni razvoj izdelkov
Published in DKUM: 10.05.2024; Views: 366; Downloads: 34
Full text (5,67 MB)
This document has many files! More... |
3. Numerical analysis of a wind turbine blade with different softwareGorazd Hren, 2019, original scientific article Abstract: The development of wind power generation technology recognises the wind turbine blade design and manufacturing as crucial for its performance. The laboratory size wind turbine blade was analysed, considering the 3D printing plastic material for blades. Applying the structural dynamic equations of blades, the aero-elastic model of the rotating rotor and the numerical simulation method of the deflections are presented under the aerodynamic loads and centrifugal forces. Based on the parameters of aerofoil and the geometrical parameters of blade, 3D model of the blade was established with the modelling software. Then the model was introduced into computational flow dynamics software to carry out the loads on the blade and further into numerical structural analysis. The analysis was performed in two different software packages. Design of wind turbine blades depends on high precision, reliable and robust numerical predictions of performance where the plug-in software is found to be inadequate for nontrivial problems.
Keywords: computational fluid dynamics, numerical analysis, structural analysis, wind turbine blade
Published in DKUM: 22.02.2024; Views: 332; Downloads: 27
Full text (1,68 MB)
This document has many files! More... |
4. Cavitation erosion modelling : comparison of different driving pressure approachesLuka Kevorkijan, Marko Pezdevšek, Ignacijo Biluš, Gorazd Hren, 2023, original scientific article Abstract: In this paper we compared different driving pressure approaches to calculate the cavitation potential energy from a source, which is transferred to a surface. The first approach used the reference pressure, the second approach used the pressure calculated at each timestep with no averaging, the third approach used the averaged pressure values from all timesteps included in one shedding cycle, and the last approach used pressure values from the steady state simulations results. The results show that for all formulations the averaged pressure values and steady state pressure values give similar results in terms of mean potential power distribution on the hydrofoil surface as in absolute values. The reference pressure approach gave similar results for the derivative and divergence formulation while for the source term the mean potential power distribution on the hydrofoil surface differs and the maximums were near the leading edge. The approach where we used no pressure averaging gave adequate results in terms of mean potential power distribution but differs from other approaches in absolute values which were considerably lower for all potential power formulations.
Keywords: cavitation, erosion potentional, driving pressure, numerical simulations
Published in DKUM: 21.02.2024; Views: 400; Downloads: 24
Full text (796,29 KB)
This document has many files! More... |
5. Primerjava sistemov CAD (Solidworks in Onshape) pri 3D modeliranju : diplomsko deloJan Gabrijel, 2023, undergraduate thesis Abstract: Programska oprema za računalniško podprto konstruiranje je stalnica pri razvoju izdelkov in ima velik vpliv na različne tehnologije in sisteme proizvodnje v raznovrstnih panogah. Razvoj in uporaba teh sistemov je ključno spremenila tradicionalne metode razvoja izdelkov vse od prototipa do končne proizvodnje. Čeprav se teoretske metode modeliranja ne spreminjajo veliko, je njihov razvoj v zadnjem času predvsem usmerjen na prilagajanje vedno močnejši strojni opremi, kakovosti prikazovanja in predvsem soočanja s številnimi izzivi kot so dostopnost do skupnih podatkovnih baz, komunikacija preko računalniških mrež, težave z verzijami ter stroški strojne opreme in licenciranja.
Novejša programska oprema CAD v oblaku, uporabnikom ponuja novo in drugačno storitev, ki ne zahteva namestitve programske opreme in licenciranje, in je enostavno dosegljiva iz internetnega prikazovalnika. Programska oprema v oblaku na splošno sicer še ne odgovarja na vsa vprašanja, ki se ob pojavljajo ob uporabi, vendar že prinaša nove pristope, ki nakazujejo smernice drugačne uporabe sistemov CAD.
V diplomski nalogi smo na primeru geometrije sklopa parnega stroja primerjali sistema CAD: Solidwoks kot tradicionalni sistem CAD in Onshape kot primer sistema CAD v oblaku. Namen diplomske naloge je uporabniška izkušnja dveh programskih sistemov CAD na enakem izdelku katere rezultat so številni dejavniki, ki jih je potrebno upoštevati. Ugotovimo lahko, da je uporabniška izkušnja zelo podobna, a je prednost, ob zagotovljeni varnosti podatkov na strani oblačnih storitev.
Keywords: sistemi CAD, modeliranje, računalništvo v oblaku
Published in DKUM: 16.01.2024; Views: 389; Downloads: 21
Full text (2,95 MB) |
6. Vizualizacija temperaturne porazdelitve na podlagi meritev : diplomsko deloKatja Zapušek, 2023, undergraduate thesis Abstract: Pri postavitvah novih in obnovi starejših prostorov je temperatura zelo pomemben
dejavnik. S pomočjo senzorjev lahko temperaturo izmerimo in jo vizualno predstavimo v
realnem 3D-prostoru. Prostor, ki ga predstavimo v končnem programu, razdelimo na
enakomerno razporejene enote. Vsak senzor zavzema svojo enoto, ostale enote
predstavljajo izračunane temperature skozi interpolacijo. V enotah so določene in
izračunane temperature predstavljene z določeno barvo. Vsako posamezno enoto lahko
tudi zmanjšamo. Z zmanjšanjem ene enote pridobimo gostejšo mrežo in natančnejšo
sliko barv ter temperatur.
Keywords: prostorska računalniška vizualizacija, temperaturno polje, X3D
Published in DKUM: 16.01.2024; Views: 265; Downloads: 24
Full text (2,27 MB) |
7. Influence of Numerical Mesh Type on Airfoil Aerodynamic CharacteristicsMarko Pezdevšek, Matej Fike, Andrej Predin, Gorazd Hren, 2019, published scientific conference contribution Abstract: In this paper, we will examine how different mesh types affect the aerodynamic characteristic of an airfoil. The airfoil used for this paper was the NREL S809. Three different mesh types were created, a blocked structured mesh, an unstructured mesh and a hybrid mesh containing a blocked structured mesh near the surface of the airfoil and an unstructured mesh on the outside perimeter. Steady state simulations were performed for angles of attack between 0°and 22°. Lift and drag coefficient for all created meshes were compared to experimental results from literature. From angles of attack between 2° and 8° all three meshes predict similar lift and drag coefficients. We encountered problems with convergence for the unstructured mesh at angles of attack higher than 8°. Structured and hybrid mesh had similar lift and drag coefficients across all angles of attack.
Keywords: computational fluid dynamics, NREL S809, structured mesh, unstructured mesh, hybrid mesh
Published in DKUM: 04.12.2023; Views: 361; Downloads: 28
Full text (18,06 MB)
This document has many files! More... |
8. Experimental and Numerical Research of Micro Wind Turbine for Low Wind SpeedsMatej Fike, Marko Pezdevšek, Andrej Predin, Gorazd Hren, 2019, published scientific conference contribution Abstract: In this paper, experimental and numerical study of micro wind turbine for low wind speeds is presented. Numerical simulations were performed for two turbines with different blades at various wind speeds. The first geometry was NTNU turbine and the second was modified NTNU turbine with shorter blades. Results from the numerical study showed that more efficient with higher power coefficient is turbine with modified blades.
Keywords: wind turbine, NREL S826, CFD, power coefficient, structured mesh
Published in DKUM: 04.12.2023; Views: 301; Downloads: 28
Full text (18,06 MB)
This document has many files! More... |
9. Methodology of immersive video application : the case study of a virtual tourJure Jazbinšek, Gorazd Hren, 2021, original scientific article Abstract: A Virtual Tour is an interactive presentation of real places accessible directly with an Internet browser with no additional installations of apps of plugins. Once, 360° photos are recorded and processed (stitched into spherical panoramas), editing of a Virtual Tour (walk) enables connection of spherical panoramic photos (or videos) into interactive presentations. For an enhanced experience and stand-alone presenting ability, features are added, like natural-sounding voice for text-to-speech descriptions and embedded videos. During multiple virtual tour presentations, users, viewers and presenters reported exceptional usability and an immersive experience. Virtual Tours have great potential to reshape the future education process and establish a new benchmark for presentation. The Virtual Tours application is expected to be used in education, tourism and future building sites or industry, as a key component for workforce briefings, and “as build” documenting of various stages of build, with the possibilities to integrate into Building Information Modelling (BIM) models.
Keywords: virtual tour, 360 camera, RICOH THETA Z1, 3dVista, Text to Speech
Published in DKUM: 13.11.2023; Views: 443; Downloads: 5
Full text (2,21 MB)
This document has many files! More... |
10. Static model of temperature distribution in a photovoltaic moduleKlemen Sredenšek, Sebastijan Seme, Gorazd Hren, 2021, original scientific article Abstract: The primary objective of this paper is to present a static model for calculating the temperature distribution in a photovoltaic module using the finite element method. The paper presents in more detail the theoretical background of solar radiation, heat transfer, and the finite element method. The results of the static model are evaluated using temperature measurements of a photovoltaic model, which were performed at the Institute of Energy Technology, Faculty of Energy Technology, University of Maribor. The results of the regression analysis show a good concurrence between the measured and modelled values of the temperature of the photovoltaic module, especially on days with a higher share of the direct component of solar radiation.
Keywords: photovoltaic module, temperature distribution, heat transfer, finite element method
Published in DKUM: 13.11.2023; Views: 274; Downloads: 7
Full text (2,01 MB)
This document has many files! More... |
