Towards a hybrid CFD platform for investigating aircraft trailing vortices

Simple item page
dc.contributor.advisorMalan, Arnaud Gen_ZA
dc.contributor.advisorNordström, Jen_ZA
dc.contributor.authorChangfoot, Donovan Men_ZA
dc.date.accessioned2018-01-23T12:06:59Z
dc.date.available2018-01-23T12:06:59Z
dc.date.issued2017en_ZA
dc.description.abstractThis dissertation outlines the development of a parallel 3D hybrid finite-volume- finite-difference solver. As motivation for such a scheme, the specific application area under consideration is modeling the trailing vortices shed from the wings of aircraft under transonic flight conditions. For this purpose, the Elemental® finite volume code is employed in the vicinity of the aircraft, while the Essense finite difference software is employed to accurately resolve the trailing vortices. The former method is spatially formally 2nd order and the latter set to 6th order accurate. The coupling of the two methods is achieved in a stable manner through the use of Summation-by-Parts operators and weak imposition of boundary conditions through Simultaneous-Approximation-Terms (SBP-SAT). Accordingly, a special parallel SBP-SAT interface library is developed in Elemental®. In addition, the code is extended to impose boundary conditions in a weak manner via the SBP-SAT framework; as well as interface volume definitions changed to allow coupling with the 6th order code. The developed hybrid solver is successfully validated against analytical test-cases. This is followed by demonstrating its ability to model the flow field, including trailing vortex structures, around the NASA Common-Research-Model (CRM) under transonic flow conditions. Inviscid flow was assumed and the trailing vortices from both wing and horizontal stabiliser accurately resolved to 3 and 1 reference chords downstream of the lifting surface respectively. The robustness of the interface treatment is demonstrated by the smoothness of the flow solution across an interface boundary in the presence of high flow gradients and rapidly changing mesh topology. In addition, high vortex axial flow gradients were predicted while the vortex core speed is 6 % slower than free-stream.en_ZA
dc.identifier.apacitationChangfoot, D. M. (2017). <i>Towards a hybrid CFD platform for investigating aircraft trailing vortices</i>. (Thesis). University of Cape Town ,Faculty of Engineering & the Built Environment ,Department of Mechanical Engineering. Retrieved from http://hdl.handle.net/11427/26905en_ZA
dc.identifier.chicagocitationChangfoot, Donovan M. <i>"Towards a hybrid CFD platform for investigating aircraft trailing vortices."</i> Thesis., University of Cape Town ,Faculty of Engineering & the Built Environment ,Department of Mechanical Engineering, 2017. http://hdl.handle.net/11427/26905en_ZA
dc.identifier.citationChangfoot, D. 2017. Towards a hybrid CFD platform for investigating aircraft trailing vortices. University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Changfoot, Donovan M AB - This dissertation outlines the development of a parallel 3D hybrid finite-volume- finite-difference solver. As motivation for such a scheme, the specific application area under consideration is modeling the trailing vortices shed from the wings of aircraft under transonic flight conditions. For this purpose, the Elemental® finite volume code is employed in the vicinity of the aircraft, while the Essense finite difference software is employed to accurately resolve the trailing vortices. The former method is spatially formally 2nd order and the latter set to 6th order accurate. The coupling of the two methods is achieved in a stable manner through the use of Summation-by-Parts operators and weak imposition of boundary conditions through Simultaneous-Approximation-Terms (SBP-SAT). Accordingly, a special parallel SBP-SAT interface library is developed in Elemental®. In addition, the code is extended to impose boundary conditions in a weak manner via the SBP-SAT framework; as well as interface volume definitions changed to allow coupling with the 6th order code. The developed hybrid solver is successfully validated against analytical test-cases. This is followed by demonstrating its ability to model the flow field, including trailing vortex structures, around the NASA Common-Research-Model (CRM) under transonic flow conditions. Inviscid flow was assumed and the trailing vortices from both wing and horizontal stabiliser accurately resolved to 3 and 1 reference chords downstream of the lifting surface respectively. The robustness of the interface treatment is demonstrated by the smoothness of the flow solution across an interface boundary in the presence of high flow gradients and rapidly changing mesh topology. In addition, high vortex axial flow gradients were predicted while the vortex core speed is 6 % slower than free-stream. DA - 2017 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 2017 T1 - Towards a hybrid CFD platform for investigating aircraft trailing vortices TI - Towards a hybrid CFD platform for investigating aircraft trailing vortices UR - http://hdl.handle.net/11427/26905 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/26905
dc.identifier.vancouvercitationChangfoot DM. Towards a hybrid CFD platform for investigating aircraft trailing vortices. [Thesis]. University of Cape Town ,Faculty of Engineering & the Built Environment ,Department of Mechanical Engineering, 2017 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/26905en_ZA
dc.language.isoengen_ZA
dc.publisher.departmentDepartment of Mechanical Engineeringen_ZA
dc.publisher.facultyFaculty of Engineering and the Built Environment
dc.publisher.institutionUniversity of Cape Town
dc.subject.otherEngineeringen_ZA
dc.titleTowards a hybrid CFD platform for investigating aircraft trailing vorticesen_ZA
dc.typeMaster Thesis
dc.type.qualificationlevelMasters
dc.type.qualificationnameMSc (Eng)en_ZA
uct.type.filetypeText
uct.type.filetypeImage
uct.type.publicationResearchen_ZA
uct.type.resourceThesisen_ZA
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
thesis_ebe_2017_changfoot_donovan_m.pdf
Size:
21.73 MB
Format:
Adobe Portable Document Format
Description:
Download
Collections
Masters