Numerička simulacija pokusa otpora

undergraduate thesis

• Title (english): Numerical simulation of the resistance test
• Author: Dominik Pribanić
• Mentor: Nastia Degiuli (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2019-03-01, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Shipbuilding; Hydromechanics of Floating and Maritime Structures

Abstract

U ovom radu prikazana je numerička simulacija pokusa otpora modela broda primjenom računalne dinamike fluida (RDF) s ciljem određivanja ukupnog otpora modela broda. Numeričke simulacije provedene su primjenom komercijalnog programskog paketa STAR-CCM+ unutar kojega je generirana proračunska mreža, postavljeni rubni uvjeti te fizikalne postavke numeričke simulacije. Numeričke simulacije provedene su korištenjem modela nestacionarnog trodimenzijskog strujanja viskoznog fluida sa slobodnom površinom temeljenog na Reynoldsovim osrednjenim Navier-Stokesovim (engl. Reynolds Averaged Navier-Stokes, RANS) jednadžbama, uz primjenu modela turbulencije. Prilikom zadavanja rubnih uvjeta na nepropusnoj stijenci modela broda korištene su zidne funkcije. Dobiveni rezultati verificirani su za jedan Froudeov broj pri čemu je ispitan utjecaj gustoće mreže te vremenskog koraka. Prema dobivenim rezultatima odabrana je mreža te vremenski korak, koji predstavljaju kompromis između točnosti i potrebnog proračunskog vremena. Numeričke simulacije za preostala tri Froudeova broja provedene su primjenom odabrane gustoće mreže i vremenskog koraka. Dobiveni rezultati validirani su usporedbom s eksperimentalnim rezultatima dostupnim u literaturi. Pokazano je da se numeričkim simulacijama viskoznog strujanja oko modela broda mogu dobiti zadovoljavajući rezultati.

Abstract (english)

In this study the numerical simulation of the resistance test for a ship model is presented using Computational Fluid Dynamics (CFD) in order to determine total resistance of a ship model. Numerical simulations are carried out utilizing the commercial software package STAR-CCM+ within which the grid is generated, and the boundary conditions and physical settings are set up. Numerical simulations are carried out using an unsteady three-dimensional viscous flow model with free surface based on Reynolds averaged Navier-Stokes (RANS) equations utilizing turbulence model. Wall functions are used to set up the boundary conditions on the hull of the ship model. The obtained results are verified for one Froude number, i.e. the influence of grid density and time step are examined. Based on the obtained results, a grid density and a time step are chosen as a compromise between the accuracy and the required computational time. Numerical simulations for the remaining three Froude numbers are carried out using the chosen grid density and time step. The obtained results are validated by comparison with the experimental results available in the literature. It has been shown that numerical simulations of viscous flow around the ship model can provide satisfactory results.

• Keywords: pokus otpora; računalna dinamika fluida (RDF); STAR-CCM+; RANS; k-ɛ model turbulencije
• Keywords (english): resistance test; Computational Fluid Dynamics (CFD); STAR-CCM+; RANS; k-ɛ turbulence model
• Language: croatian
• URN:NBN: urn:nbn:hr:235:991301
• 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: 2019-05-23 00:22:12