Analiza strujanja i prijelaza topline u odjeljku motora lakog zrakoplova korištenjem numeričke mehanike fluida

Zrnić, Dino (2018) Analiza strujanja i prijelaza topline u odjeljku motora lakog zrakoplova korištenjem numeričke mehanike fluida. = Thermal Management Analysis in the Engine Compartment of a Light Aircraft using Computational Fluid Dynamics. Master's thesis (Bologna) , Sveučilište u Zagrebu, Fakultet strojarstva i brodogradnje, UNSPECIFIED. Mentor: Jasak, Hrvoje.

[img]
Preview
Text
Diplomski_rad_Dino_Zrnic2018.pdf - Published Version Jezik dokumenta:English

Download (19MB) | Preview
[img] Text
Zrnić_Dino_autorska_izjava_diplomski_2018.pdf - Published Version
Restricted to Repository staff only Jezik dokumenta:Croatian

Download (528kB)

Abstract (Croatian)

U ovom radu predstavljen je prikaz hladenja i analiza strujanja i prijelaza topline u odjeljku motora lakog zrakoplova korištenjem numeričke mehanike fluida. Kako propeler ima veliki utjecaj na ulaznu struju zraka u odjeljak motora gdje se odvija hladenje, napravljena je zasebna numerička simulacija rada propelera. Ovom simulacijom proučavani su stlačivi efekti strujanja s ciljem dobivanja točnih sila i momenata za veće područje rada motora. Ti podatci su potrebni kako bi se pomoću teorije diska postavili uvjeti za sljedeću numeričku simulaciju koja obuhvaća prijelaz topline s motora na okolni zrak. U ovoj numeričkoj simulaciji disk je postavljen na mjesto propelera, tj. ispred difuzora, te se računa i prikazuje karakteristika strujanja fluida koji prvo ulazi u difuzor, a potom u odjeljak motora hladenog zrakom. Takoder je izračunata toplina koja se prenosi samo konvekcijom na orebrenim površinama. Nadogradena su tri nova modela izmjenjivača topline unutar algoritma za proračun stlačivog strujanja. Ti modeli su testirani i validirani na jednostavnom primjeru cijevi kvadratnog presjeka. Na kraju su prikazani rezultati numeričke simulacije povezanih dijelova propelera i odjeljka motora čiji rezultati su dobiveni zasebnim numeričkim simulacijama.

Abstract

In this thesis the cooling system of an engine in a light aircraft influenced by a propeller is simulated. Firstly, investigation is made for aircraft propeller separately, in order to examine air compressibility effects of the flow around the propeller and to determine the performance of the propeller. The second set of simulations deals with heat transfer in the engine compartment of the Pipistrel Panthera aircraft. Computational domains for the propeller and the engine cooling system are made separately for each case. In order to calculate heat transfer in the engine compartment three new heat exchanger models have been implemented and upgraded with porous media effects inside the compressible flow solver: Total Volumetric Heat model, Single stream model and the Nusselt model. Implemented models are validated on a simple test case and comparison of the results is presented. After successful validation heat transfer simulations are performed for engine cooling. Finally, a steady compressible CFD simulation of the flow with heat transfer is performed for the engine compartment case using the actuator disk model and the integral heat exchanger model. Actuator disk theory which uses calculated force and moment data from the aircraft propeller case has been implemented in order to study influence of propeller wakes and fluid flow on the cooling system of engine compartment.

Item Type: Thesis (Master's thesis (Bologna))
Uncontrolled Keywords: stlačivost, CFD, prijelaz topline, foam-extend, zrakoplovni propeler, hladenje, model izmjenjivača, porozni medij
Keywords (Croatian): compressible, CFD, foam-extend, aircraft propeller, heat transfer, cooling, exchanger model, porous media
Subjects: TECHNICAL SCIENCE > Mechanical Engineering
TECHNICAL SCIENCE > Aviation, rocket and space technology
Date Deposited: 19 Jan 2018 10:49
Last Modified: 19 Jan 2021 05:39
URI: http://repozitorij.fsb.hr/id/eprint/8262

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year