A novel approach to reduce the computation time for CFD; hybrid LES–RANS modelling on parallel computers

Show simple item record

dc.contributor.advisor Thompson, Chris en_UK
dc.contributor.author Turnbull, Julian en_UK
dc.date.accessioned 2005-11-23T14:32:53Z
dc.date.available 2005-11-23T14:32:53Z
dc.date.issued 2003 en_UK
dc.identifier.uri http://hdl.handle.net/1826/104
dc.description.abstract Large Eddy Simulation is a method of obtaining high accuracy computational results for modelling fluid flow. Unfortunately it is computationally expensive limiting it to users of large parallel machines. However, it may be that the use of LES leads to an over-resolution of the problem because the bulk of the computational domain could be adequately modelled using the Reynolds averaged approach. A study has been undertaken to assess the feasibility, both in accuracy and computational efficiency of using a parallel computer to solve both LES and RANS type turbulence models on the same domain for the problem flow over a circular cylinder at Reynolds number 3 900 To do this the domain has been created and then divided into two sub-domains, one for the LES model and one for the kappa - epsilon turbulence model. The hybrid model has been developed specifically for a parallel computing environment and the user is able to allocate modelling techniques to processors in a way which enables expansion of the model to any number of processors. Computational experimentation has shown that the combination of the Smagorinsky model can be used to capture the vortex shedding from the cylinder and the information successfully passed to the kappa - epsilon model for the dissipation of the vortices further downstream. The results have been compared to high accuracy LES results and with both kappa - epsilon and Smagorinsky LES computations on the same domain. The hybrid models developed compare well with the Smagorinsky model capturing the vortex shedding with the correct periodicity. Suggestions for future work have been made to develop this idea further, and to investigate the possibility of using the technology for the modelling of mixing and fast chemical reactions based on the more accurate prediction of the turbulence levels in the LES sub-domain. en_UK
dc.format.extent 1883 bytes
dc.format.extent 5281283 bytes
dc.format.mimetype text/plain
dc.format.mimetype application/pdf
dc.language.iso en_UK en_UK
dc.publisher Cranfield University en_UK
dc.subject.other Parallel computing en_UK
dc.subject.other Turbulence en_UK
dc.subject.other Large Eddy Simulation en_UK
dc.subject.other Smagorinsky model en_UK
dc.title A novel approach to reduce the computation time for CFD; hybrid LES–RANS modelling on parallel computers en_UK
dc.type Thesis or dissertation en_UK
dc.type.qualificationlevel Doctoral
dc.type.qualificationname PhD
dc.publisher.department School of Engineering

Files in this item

This item appears in the following Collection(s)

Show simple item record

Search CERES


My Account