Numeričko određivanje faktora forme trimarana

undergraduate thesis

• Title (english): Numerical assessment of the form factor of trimaran
• Author: Ivan Oreč
• Mentor: Nastia Degiuli (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2019-09-26, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Shipbuilding; Hydromechanics of Floating and Maritime Structures

Abstract

U ovom radu provedeno je istraživanje faktora forme za pet različitih trimaranskih konfiguracija Wigley-eve serije C98-349. Istražen je utjecaj rasporeda simetričnih bočnih trupova u odnosu na srednji trup na faktor forme primjenom računalne dinamike fluida (RDF). U tu svrhu provedeno je deset numeričkih simulacija koristeći programski paket STAR-CCM+ za trimaranske konfiguracije k1, k2, k3, k4 i k7 te za jednotrupni brod. Prikazan je matematički model koji rješava Reynoldsove osrednjene Navier-Stokesove jednadžbe (RANS) te je odabran model turbulencije
k-ω SST. Numerički izračunati faktori forme validirani su usporedbom s eksperimentalno dobivenim vrijednostima faktora forme. Prikazane su i komentirane raspodjele tlaka po oplakanoj površini za svaku trimaransku konfiguraciju. Rezultati pokazuju kako je uslijed viskozne interferencije faktor forme trimarana veći u odnosu na faktor forme jednotrupnog broda. Dobiveni rezultati ukazuju na to da trimaranske konfiguracije s većim bočnim razmakom trupova imaju manje vrijednosti faktora forme. Pokazano je da se računalna dinamika fluida može koristiti kao praktičan alat za određivanje faktora forme jednotrupnih i višetrupnih brodova.

Abstract (english)

The investigation on the form factor for five different trimaran configurations of Wigley series C98-349 is carried out in this thesis. The influence of trimaran layout on form factor is assessed using Computational Fluid Dynamics (CFD) by performing ten numerical simulations utilizing software package STAR-CCM+ for trimaran configurations k1, k2, k3, k4, k7 and monohull. Mathematical model based on Reynolds Averaged Navier-Stokes equations (RANS) is presented and k-ω SST turbulence model is selected. The numerically obtained form factors are validated by comparison with experimentally obtained values from factors. Pressure distributions on wetted surface for each trimaran configuration are also shown and discussed. Form factor of trimaran configuration is larger than the form factor of monohull due to the occurence of viscous interference. The obtained results show that trimaran configurations with larger separations have smaller values of form factors. It is shown that CFD can be used as a practical tool for the determination of form factors for both monohull and multihull vessels.

• Keywords: faktor forme; trimaranska konfiguracija; Wigley-eva serija; računalna dinamika fluida (RDF); Reynoldsove osrednjene Navier-Stokesove jednadžbe (RANS); k-ω SST model turbulencije; udvojeni model
• Keywords (english): form factor; trimaran configuration; Wigley's series; Computational Fluid Dynamics (CFD); Reynolds Averaged NAvier-Strokes equations (RANS); k-ω SST turbulence model; double body
• Language: croatian
• URN:NBN: urn:nbn:hr:235:424462
• 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: 2019-09-24 09:26:38