Utjecaj položaj ruku na aerodinamičke karakteristike skijaša letača

Golubić, Dino (2016) Utjecaj položaj ruku na aerodinamičke karakteristike skijaša letača. = Aerodynamic characteristics of ski jumper influenced by position of his arms. Undergraduate thesis , Sveučilište u Zagrebu, Fakultet strojarstva i brodogradnje, UNSPECIFIED. Mentor: Kozmar, Hrvoje.

Preview

Text Golubić_2016_završni_prediplomski.pdf - Published Version Jezik dokumenta:Croatian Download (6MB) | Preview

Abstract (Croatian)

U ovom završnom radu istražen je utjecaj položaja ruku skijaša letača na duljinu njegova skoka. Duljina skoka velikim je dijelom uvjetovana odnosom sile uzgona i otpora skijaša pa su te dvije aerodinamičke sile te njihov omjer promatrani tijekom numeričke analize. Tijelo skijaša letača modelirano je u CAD programskom paketu SolidWorks na pojednostavljeni način kako je i prethodno bilo modelirano u sličnim radovima. Modelirana su tri modela skijaša letača s različitim položajem ruku u odnosu na tijelo: a) ruke pod 0° (uz tijelo), b) ruke pod 45°, c) ruke pod 90°. Proračunska domena s jednom ravninom simetrije napravljena je u programskom paketu Salome. Domena je strukturirano ispunjena mrežom heksaedarskih konačnih volumena uz veća profinjenja u blizini tijela skijaša uz korištenje programskog paketa cfMesh. Numerički proračun proveden je u računalnom programu OpenFOAM uz stacionarne uvjete strujanja. Uz aerodinamičke sile otpora i uzgona u radu su prikazana i polja tlaka i brzine oko tijela skijaša te je provedena diskusija rezultata.

Abstract

In this bachelor thesis, the aerodynamic forces experienced by a generic ski jumper are studied. The focus is on the position of ski jumper’s arms with respect to his body. As the length of the jump is largely determined by the lift to drag force ratio of the ski jumper, these two aerodynamic forces are analyzed using Computational Fluid Dynamics (CFD) simulations. Ski jumper’s body is modeled in the SolidWorks CAD software package in a simplified way similar to previous studies. Three models of the ski jumper with different placement of arms with respect to his body are modeled, i.e. a) arms at 0° (close to body), b) arms at 45° , c) arms at 90° . Computational domain with one symmetry plane is created in the Salome software package. The domain is structurally filled with the grid of hexahedron cells along with refinements close to the ski jumper‘s body using the cfMesh software package. The CFD simulations are carried out using the OpenFOAM software package, SST k− ω turbulence model and stationary flow conditions. The aerodynamic drag and lift forces, as well as pressure and velocity fields around the ski jumper are reported and discussed.

Item Type:	Thesis (Undergraduate thesis)
Uncontrolled Keywords:	Računalna dinamika fluida; metoda konačnih volumena; omjer sile uzgona i otpora; skijaš letač
Keywords (Croatian):	Computational fluid dynamics, finite volume method, lift-to-drag ratio, ski jumper
Subjects:	TECHNICAL SCIENCE > Mechanical Engineering
Divisions:	500 Department of Energy, Power Engineering and Environment > 520 Chair of Fluid Mechanics
Date Deposited:	08 Mar 2016 14:22
Last Modified:	08 Mar 2016 14:22
URI:	http://repozitorij.fsb.hr/id/eprint/5209

Actions (login required)

View Item