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Ovaj rad bavi se aerodinamikom aviona. Prvi dio rada odnosi se na izradu 3D modela aviona s prilagođenim novim krilom, odnosno NACA 2411 profilom u programu Autodesk Inventor. Nakon izrade 3D modela, korišten je Hypermesh za izradu numeričke mreže. Dobivena numerička mreža ubačena je u Virtual Wind Tunnel gdje je provedeno nekoliko simulacija koje su uspoređene i na temelju kojih su doneseni zaključci., The topic of this final thesis is the aerodynamics of airplanes. The first part refers to the creation of a 3D model of the airplane with an adapted new wing NACA 2411 profile in the Autodesk Inventor program. After a 3D model was created, Hypermesh was used to create the numerical mesh. The resulting numerical network was inserted into Virtual Wind Tunnel, where several simulations were performed, compared, and based on which conclusions were drawn.

Prvim dijelom ovog završnog rada objašnjene su sve teorijske osnove vezane za fizikalne veličine koje se javljaju u daljnjim razmatranjima i u razmatranju aerodinamike općenito. Daljnjim ulaskom u problematiku zadatka definirane su vrste strujanja fluida i osnove aerodinamike zgrada. Za praktični dio završnog rada promatrana je jednostavna geometrija kocke koja sukladno stvarnosti najbolje opisuje model zgrada u simulacijama. Pojašnjenjem računalne dinamike fluida i korištenih programa u samoj izradi simulacija i analiza, došlo se je do brojčanih i grafičkih rezultata generiranih post-procesorom za dva različita slučaja opstrujavanja neaerodinamičnog tijela. Prema dobivenim podacima izveo se kratak zaključak temeljen na ključnim razlikama između dvije simulacije, a na samom kraju izveden je zaključak o cjelokupnom radu i računalnoj dinamici fluida., The first part of this final paper explains all the theoretical bases related to fluid mechanics and aerodynamics in general. Moving deeper into the problems of the task, the types of fluid flow and the basics of building aerodynamics are defined. For the practical part of the final work, a simple geometry of a cube was observed, which is the best description of the building model in simulations and in reality. By using computational fluid dynamics methods and related programs for the creation of simulations and analyses, numerical and graphical results generated by the post-processor for two different cases of obstruction of a non-aerodynamic body were obtained. According to the obtained data, a short conclusion was given, which was based on the key differences between the two simulations. Also, at the very end, a conclusion was drawn about the overall CFD and data in this paper.

U ovom završnom radu je generalno objašnjeno područje aerodinamike unutar Mehanike Fluida. Izrađen je 3D model Airbusa A320 sprofilom krila NACA 4415 u programu SolidWorks. Za izradu simulacije je upotrijebljen program Altair HyperWorks. Numerička mreža 3D modela izrađena je u HyperMeshu te je ista kasnije ubačena u Virtual Wind Tunnel. Provedeno je više simulacija s različitim postavkama strujanja fluida da možemo usporediti dobivene rezultate te izvući zaključak., This final thesis generally explains the area of aerodynamics in Fluid Mechanics. 3D model of Airbus A320 with NACA 4415 wing profile was made in SolidWorks. For simulation purposes, Altair HyperWorks was used. Numerical mesh for the 3D model was made in HyperMesh and imported into Virtual Wind Tunnel for simulations. Multiple simulations were made with different presets for fluid flow so we could compare results and draw a conclusion.

U ovom radu istražena je promjena hidrodinamičkog otpora jedrilice klase Optimist sa promjenom bočnog nagiba. Proračun je izveden korištenjem metode konačnih volumena na nestrukturiranoj nepomaknutoj mreži. Korišten je već postojeći model jedrilice u obliku STEP datoteke. Izrađeno je 11 simulacija, po jedna za svaki kut nagiba od 0 do 20°. Modeli geometrije domene su izrađeni u programskom paketu Salome, dok je za prostornu diskretizaciju korišten paket cfMesh. Proračuni su obavljeni SIMPLE postupkom za stacionarna strujanja, pomoću programa simpleFOAM- jednog od programa biblioteke OpenFOAM, a korišteni model turbolencije je k-ω SST model. Brzina jedrilice je konstantna, a iznosi 1.5 m/s. Rezultati se naknadno obrađuju pomoću ParaView i Gnuplot programskih paketa. In this work the influence of lateral tilt angle on hull drag force of the class Optimist sailboat is studied. The calculations were performed using Finite Volume Method on unstructural grids. The sailboat geometry, being defined in previous studies, was aquired in form of STEP format file. A total of 11 simulations were performed, each for different tilt angle in range 0° - 20°. The geometry models of the domain were created using Salome software package, while for the spatial discretisation the cfMesh package was used. Steady, incompressible turbulent flow model was used and the calculations were performed using SIMPLE algorithm and k-ω SST turbulence model, as implemented in the OpenFOAM library. The sailboat velocity was kept constant, of value of 1.5 m/s. The results are post-procesing using ParaView and Gnuplot packages.

U ovom radu se ispituje utjecaj promjene uzdužnog nagiba i dubine urona kobilice na hidrodinami čki otpor uronjenog dijela jedrilice klase Optimist. Istisnina je izračunata za ukupnu masu jedrilice i jedriličara od 80 kg. U proračunu je uzeta brzina jedrilice od 1,5 m/s. Za sve slučajeve proračunska domena je diskretizirana korištenjem računalnih programa Salome i cfMesh. Numeri čki proračun za stacionarne uvjete strujanja uz zanemaren utjecaj valova je izvršen u programskom paketu OpenFOAM. U radu je su prikazani i analizirani rezultati te su prikazana polja brzine i tlaka za najzanimljivije slučaje. Goal of this work is to determinate the influence of pitch angle and keel depth on drag force of sail-boat class Optimist hull. Drag force is analyzed for the sail-boat cruise velocity of 1.5 m/s. Computational domain is discretizated using Salome and cfMesh program package, and various cases of pitch angle and keel depth where studied. Numerical analysis for stationary flow conditions is executed in OpenFOAM program package. The results are presented trough velocity and pressure fields of most interesting cases, so as in form of force-pitch angle diagrams.