Shape optimisation of an integrated bulb-keel
dc.contributor | Aalto-yliopisto | fi |
dc.contributor | Aalto University | en |
dc.contributor.advisor | Larsson, Lars | |
dc.contributor.advisor | Vesting, Florian | |
dc.contributor.advisor | Orych, Michal | |
dc.contributor.author | Ljungqvist, Kasper | |
dc.contributor.department | Sovelletun mekaniikan laitos | fi |
dc.contributor.school | Insinööritieteiden korkeakoulu | fi |
dc.contributor.school | School of Engineering | en |
dc.contributor.supervisor | Matusiak, Jerzy | |
dc.date.accessioned | 2020-12-23T17:33:14Z | |
dc.date.available | 2020-12-23T17:33:14Z | |
dc.date.issued | 2011 | |
dc.description.abstract | The objective of the thesis was to shape optimise an integrated bulb-keel using a numerical optimisation method and to validate how well the used methods suit this kind of problem. The algorithm used for the optimisation was a Non-dominated Sorting Genetic Algorithm, NSGA-II. The optimisation was limited to the bulb part of the keel and 7 design variables were used together with 4 inequality constraints. The hydrodynamic performance of the keel was evaluated using a RANS viscous solver and the objective function used in the optimisation was the ratio of drag coefficient over lift coefficient CD/CL. The numerical CFD calculations were validated with experimental wind tunnel tests, which is a crucial part when investigating new types of numerical flow problems. The CFD calculations were also verified using a Least Square Root method in order to obtain the numerical uncertainty. The comparison between the wind tunnel results and the CFD results showed that the CL/CD -ratio was predicted very similarly for the numerical and experimental tests. The optimised keel design had a CD/CL-ratio improvement of around 4% compared to the initial keel design. Finally the keels were mounted on a hull of a 40-foot yacht and tested in a velocity prediction program (VPP) in order to get a more understandable performance indicator of the keels. | en |
dc.format.extent | 89 + [20] | |
dc.identifier.uri | https://aaltodoc.aalto.fi/handle/123456789/99450 | |
dc.identifier.urn | URN:NBN:fi:aalto-2020122358277 | |
dc.language.iso | en | en |
dc.programme.major | Laivanrakennusoppi | fi |
dc.programme.mcode | Kul-24 | fi |
dc.rights.accesslevel | closedAccess | |
dc.subject.keyword | keel | en |
dc.subject.keyword | bulb | en |
dc.subject.keyword | NSGA-II | en |
dc.subject.keyword | optimisation | en |
dc.subject.keyword | CFD | en |
dc.subject.keyword | RANS | en |
dc.subject.keyword | integrated bulb-keel | en |
dc.title | Shape optimisation of an integrated bulb-keel | en |
dc.title | Formoptimering av en integrerad bulbköl | sv |
dc.type.okm | G2 Pro gradu, diplomityö | |
dc.type.ontasot | Master's thesis | en |
dc.type.ontasot | Pro gradu -tutkielma | fi |
dc.type.publication | masterThesis | |
local.aalto.digiauth | ask | |
local.aalto.digifolder | Aalto_92329 | |
local.aalto.idinssi | 42756 | |
local.aalto.openaccess | no |