Numerička simulacija viskoznog strujanja oko trupa broda

master's thesis

• Title (english): Numerical simulation of the viscous flow around a ship hull
• Author: Andrea Farkas
• Mentor: Nastia Degiuli (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2016-07-14, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Shipbuilding; Hydromechanics of Floating and Maritime Structures

Abstract

Poznavanje značajki strujanja oko trupa broda predstavlja vrlo važan element u procesu projektiranja broda. Danas se najčešće za određivanje hidrodinamičkih značajki provode pokusi s modelima brodova u bazenu koji su vrlo skupi i dugotrajni. Računalnom dinamikom fluida (RDF) moguće je odrediti hidrodinamičke značajke u znatno kraćem vremenu, uz smanjenje troškova projektiranja broda. Ovim pristupom moguće je u ranoj fazi projektiranja dobiti uvid u detalje strujanja oko trupa broda te dobiti preporuku kako poboljšati određeni projekt ili pak odabrati najpovoljniji projekt za modelsko ispitivanje. U ovom radu provedena je numerička simulacija viskoznog strujanja oko trupa broda pomoću programskog paketa STAR-CCM+. Dan je matematički model koji se temelji na Reynoldsovim osrednjenim Navier – Stokesovim jednadžbama (eng. Reynolds Averaged Navier – Stokes equations), k – ε model turbulencije i metoda udjela fluida u volumenu (eng. Volume of Fluid-VOF) za opis gibanja dvofaznog medija. Također su opisani potrebni rubni uvjeti za matematički model te način diskretizacije domene. Utjecaj gustoće mreže na rezultate ukupnog otpora broda je ispitan koristeći tri gustoće mreže. Rezultati ukupnog otpora broda dobiveni numeričkim simulacijama uspoređeni su s dostupnim eksperimentalnim rezultatima. Pokazano je da je za sve tri gustoće mreže moguće postići zadovoljavajuće slaganje s eksperimentalnim rezultatima.

Abstract (english)

Knowing the characteristics of the flow around the ship hull is a very important element in the process of ship design. Nowadays, the most widely used method for the determination of the hydrodynamic characteristics is to conduct experiments with ship models in the towing tank, which is a very expensive and time consuming method. In order to determine the hydrodynamic characteristics in a much shorter period of time and to reduce the costs of ship design it is possible to use computational fluid dynamics (CFD). With this approach it is possible to gain insight into the details of the flow around the ship hull at an early design stage and to get a recommendation on how to improve a specific project or to choose the most suitable project for model testing. In this thesis, numerical simulation of viscous flow around the ship hull was carried out by use of software package STAR-CCM+. A mathematical model based on Reynolds averaged Navier – Stokes equations, k - ε turbulence model and Volume of Fluid method (VOF) for describing the motion of two-phase media are given. Also, necessary boundary conditions for the mathematical model and the method of implementation of discretization are described. The influence of the grid density on the results for the total ship resistance was investigated using three different grid densities. Results of total ship resistance, obtained by numerical simulations, were compared to available experimental results. It has been shown that for all three grid densities satisfactory agreement with experimental results can be achieved.

• Keywords: računalna dinamika fluida (RDF); metoda udjela fluida u volumenu (VOF); k – ε model turbulencije; otpor broda
• Keywords (english): Computational Fluid Dynamics (CFD); Volume of Fluid method (VOF); k- ε turbulence model; ship resistance
• Language: croatian
• URN:NBN: urn:nbn:hr:235:860554
• Study programme: Title: Naval Architecture; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka brodogradnje (magistar/magistra inženjer/inženjerka brodogradnje)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-22 17:09:11