Numerička simulacija pokusa slobodne vožnje modela brodskog vijka

undergraduate thesis

• Title (english): Numerical simulation of the open water test for marine propeller model
• Author: Deni Vlašić
• Mentor: Nastia Degiuli (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2016-03-02, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Shipbuilding; Hydromechanics of Floating and Maritime Structures

Abstract

Određivanje hidrodinamičkih značajki brodskog vijka u slobodnoj vožnji je vrlo važno provesti u ranoj fazi osnivanja broda. Hidrodinamičke značajke brodskih vijaka pouzdano se mogu odrediti ispitivanjem modela brodskih vijaka. Rezultati pokusa slobodne vožnje vijka koriste se kao osnova za projektiranje vijka za novi brod. Razvoj računalne dinamike fluida omogućio je numeričko određivanje hidrodinamičkih značajki modela brodskog vijka, što znatno skraćuje vrijeme i smanjuje troškove projektiranja brodskog vijka nove geometrije. U ovom radu su provedene numeričke simulacije slobodne vožnje brodskog vijka u svrhu ispitivanja mogućnosti primjene računalne dinamike fluida (RDF) pri projektiranju brodskog vijka. U radu je korišten programski paket otvorenog koda OpenFOAM. To je programski paket koji se zasniva na modelu viskoznog strujanja teku ́cine opisanog Reynoldsovim osrednjenim Navier - Stokesovim jednadžbama. Validacija programskog paketa OpenFOAM je provedena usporedbom rezultata dobivenih numeričkim simulacijama s eksperimentalnim podacima dostupnim u literaturi. Pri provođenju numeričkih simulacija primijenjena je metoda višestrukih referentnih koordinatnih sustava (eng. Moving Reference Frame method - MRF). MRF metoda rješava jednadžbe strujanja u rotirajućem koordinatnom sustavu brodskog vijka što omogućuje rješavanje ovog problema kao stacionarnog. Iz rezultata dobivenih numeričkim simulacijama može se zaključiti da se računalna dinamika fluida može uspješno primijeniti za simulaciju pokusa slobodne vožnje brodskog vijka te dobivanje sile poriva, momenta vijka i stupanja djelovanja vijka u slobodnoj vožnji.

Abstract (english)

Determination of open water hydrodynamic characteristics of a marine propeller is very important in the early stage of ship design. Hydrodynamic characteristics of marine propellers can be reliably determined by testing propeller models. Results of open water tests are used as the basis for the design of the propeller for a new ship. The development of computational fluid dynamics enabled the numerical determination of the hydrodynamic characteristics of the marine propeller model, which significantly shortens the time and reduces the cost of designing the new marine propeller geometry. In this study, numerical simulations of open water test are carried out with the purpose of examining the possibility of applying the computational fluid dynamics for the design of the marine propeller. In this paper, the open source software package OpenFOAM is used. This is a software package that is based on the viscous fluid flow model described with Reynolds averaged Navier-Stokes equations. Validation of the software package OpenFOAM is carried out by comparing the results obtained by numerical simulations with experimental data available in the literature. Moving Reference Frame (MRF) method is used in numerical simulations. MRF method solves the flow equations in a rotating coordinate system of the propeller which allows solving this problem as stationary one. From the results obtained by numerical simulations it can be concluded that the computational fluid dynamics can be successfully applied to simulate open water test of a marine and to obtain the thrust, torque and open water efficiency.

• Keywords: brodski vijak; pokus slobodne vožnje; računalna dinamika fluida
• Keywords (english): marine propeller; open water test; computational fluid dynamics
• Language: croatian
• URN:NBN: urn:nbn:hr:235:601068
• Study programme: Title: Naval Architecture; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka brodogradnje (sveučilišni prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka brodogradnje)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-22 16:08:09