Primjena računalne mehanike fluida u konstrukciji fenestron rotora

master's thesis

• Title (english): Application of computation fluid dynamics in fenestron rotor design
• Author: Marijan Marković
• Mentor: Željko Tuković (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2021-01-21, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Aviation, Rocket and Space Technology; Aircraft Construction and Design

Abstract

U radu je objašnjen postupak konstrukcije Fenestron rotora uz primjenu računalne mehanike fluida. Za numerički proračun strujanja korišteni su programski paketi OpenFOAM i Ansys Fluent. Proces konstrukcije rotora proveden je u tri koraka. Prvo je za zadani iznos sile na rotor odabrana primjerena veličina i oblik kućišta te je određena slika strujanja kroz rotor putem analize u Fluentu. U simulaciji je primijenjen „fan“ granični uvjet, kojim je modeliran prirast tlaka uzrokovan rotacijom lopatice i tako izračunata brzina strujanja te traženi maseni protok. Zatim je pomoću Pythona i OpenFOAMa konstruirana lopatica po segmentima primjenom simulacije strujanja kroz dvodimenzionalnu rotorsku rešetku. Za konstrukciju profila lopatice korišten je Pyhon, gdje je napisana skripta za generiranje dvodimenzionalne domene strujanja s pripadajućim aeroprofilom NACA serije 4. Ulazni parametri profila su relativna debeljina, pozicija maksimalne zakrivljenosti, zakrivljenosti srednje linije te broj diskretizacijskih segmenata. Treći dio proračuna se sastoji od kreiranja 3D modela Fenestron rotora s ciljem validacije promatranog strujanja. U trećem je koraku za opis lopatice primijenjen model rotirajućeg koordinatnog sustava. Za opis domene korištena je jedna rotorska lopatica primjenom periodičkog rubnog uvjeta što omogućava uštedu računalne snage i skraćivanje vremena trajanja simulacije.

Abstract (english)

The paper explains the procedure of Fenestron rotor construction with the application of computational fluid dynamics. OpenFOAM and Ansys Fluent software packages were used for numerical flow calculation. The rotor construction process was carried out in three steps. First, the appropriate size and shape of the housing was selected for the given amount of force on the rotor, and the image of the flow through the rotor was determined by analysis in Fluent. In the simulation, a "fan" boundary condition was applied, which modeled the pressure increase caused by the rotation of the blade and thus calculated the flow velocity and the required mass flow. Then, using Python and OpenFOAM, the blade was constructed in segments using flow simulation through a two-dimensional rotor grid. Pyhon was used to construct the blade profile, where a script was written to generate a two-dimensional flow domain with a corresponding NACA Series 4 airfoil. The input profile parameters are relative thickness, maximum curvature position, midline curvature, and number of discretization segments. The third part of the calculation consists of creating a 3D model of the Fenestron rotor with the aim of validating the observed flow. In the third step, a model of a rotating coordinate system was applied to describe the blade. One rotor blade was used to describe the domain by applying a periodic boundary condition, which saves computing power and shortens the simulation duration.

• Keywords: OpenFOAM; Fluent; Python; lopatica; Fenestron rotor; rotorska rešetka; rotirajući koordinatni sustav.
• Keywords (english): OpenFOAM; Fluent; Python; blade; Fenestron rotor; rotor cascade; moving reference frame
• Language: croatian
• URN:NBN: urn:nbn:hr:235:301103
• Study programme: Title: Aeronautical Studies; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka zrakoplovnog inženjerstva (magistar/magistra inženjer/inženjerka zrakoplovnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-01-20 15:06:11