CFD simulacija interakcije rotora male besposadne letjelice za analizu buke

master's thesis

• Title (english): CFD simulation of rotor-rotor interaction of a small unmanned aircraft for noise analysis
• Author: Fran Pipunić
• Mentor: Tessa Uroić (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2024-12-06, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Aviation, Rocket and Space Technology

Abstract

Precizno predviđanje buke propelera jedan je od ključnih alata u borbi s bukom koju proizvodi sve veći broj bespilotnih letjelica. Hibridne metode računalne aeroakustike (CAA) su jedan od načina na koji je moguće predvidjeti buku koju stvaraju propeleri takvih zrakoplova. Hibridne metode razdvajaju fenomene stvaranja zvuka i njegovog širenja čime se znatno pojednostavljuje simulacija buke. Pri tome je uobičajeno za modeliranje izvora aerodinamičke buke te buke u bliskom akustičkom polju koristiti simulacije računalne dinamike fluida (CFD).
U radu su najprije iznesene teorijske osnove na kojima počivaju hibridne metode računalne aeroakustike, a zatim su prikazani rezultati simulacija kojima se modeliraju aeroakustički izvori povezani sa strujanjem zraka oko para propelera s posebnim naglaskom na interakciju dvaju propelera. Dodatno, za inicijalizaciju polja tlaka i brzine u tranzijentnim simulacijama prethodno je provedena stacionarna simulacija strujanja oko para propelera koristeći pristup s višestrukim koordinatnim sustavima (MRF). Sve simulacije su provedene u programskom okružju otvorenog koda foam-extend, grani programskog okruženja OpenFOAM.

Abstract (english)

Accurate propeller noise prediction is one of key tools in reducing noise produced by an increasing number of small unmanned aerial vehicles (UAVs). Hybrid methods of computational aeroacoustics (CAA) are one way to achieve that prediction. Hybrid methods are based on decoupling of sound generation and sound transmission phenomena and therefore they significantly simplify overall noise prediction. One of the most common ways to resolve noise generation and the near-field noise is modelling of acoustic sources based on flow simulation results obtained through computational fluid dynamics (CFD) simulations.
Theoretical considerations on which hybrid methods of computational aeroacoustics rest are considered in the first part of this work. These considerations are followed by results of transient CFD simulations that were used to model acoustic sources around a pair of UAV propellers with special considerations on interaction between two propellers. However, before transient simulations’ results are shown, additional step was made in order to initialise transient simulations with pressure and velocity field obtained through steady-state CFD simulation using multiple reference frames approach. All of the mentioned simulations were performed in an open-source environment foam-extend, a fork of OpenFOAM environment.

• Keywords: računalna aeroakustika; CAA; računalna dinamika fluida; CFD; foam-extend; OpenFOAM; interakcija propelera; buka propelera
• Keywords (english): computational aeroacoustic (CAA); computational fluid dynamics (CFD); foam-extend; OpenFOAM; propeller noise; propeller interaction
• Language: croatian
• URN:NBN: urn:nbn:hr:235:466802
• Study programme: Title: Aeronautical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: sveučilišni/a magistar/magistra inženjer/inženjerka zrakoplovnog inženjerstva (sveučilišni/a magistar/magistra inženjer/inženjerka zrakoplovnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2024-12-07 15:13:18