April 2017 - Nektar-users - imperial.ac.uk

Nektar++ transition to C++11
by Chris Cantwell 09 Sep '17

09 Sep '17

Dear all, As part of our ongoing efforts to modernise our codebase, we are planning to transition to the C++11 standard in the near future. A consequence of this is that you will in future require a compiler which supports the C++11 standard (either as an option, such as --std=c++11, or by default). Current versions of popular compilers all fully support the standard, but older compilers may only have partial support. We recommend the following compiler versions to minimise the likelihood of problems going forward: - GCC: 4.8 or later - Clang: 3.3 or later - MSVC: 19.0 or later - Intel: 15.0 or later - PGI: 2015 or later We encourage users to test out support for basic C++11 by compiling the branch 'feature/libutils-c++11' from the code repository and updating build scripts and configuration as necessary. Please let us know if you have any problems or concerns. We will be making the transition after the Nektar++ Workshop in mid-June. Cheers, Nektar++ Development Team

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Polyhedral Meshes
by Kurt Sansom 26 Apr '17

26 Apr '17

I haven't tried using a polyhedral mesh with Nektar++ and the documentation only mentions hexahedral and tetrahedral meshes. Is anyone using polyhedral meshes with nektar++. What would that take? Regards, ~Kurt -- Kurt Sansom

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2 bugs and 1 question
by Ankang Gao 24 Apr '17

24 Apr '17

Hellow, I have found two bugs in the codes, and I listed them in the attachment. I have a question about why the backward differentiation formula starts after m_pressureCalls>2, in function void Nektar::Extrapolate::AccelerationBDF(Array< OneD, Array< OneD, NekDouble > > & array). Since when m_pressureCalls=2, we can already get a first order accuracy result. thanks Ankang

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Error in Compressible Flow Solver
by Ismael El Houas Ghouddana 22 Apr '17

22 Apr '17

Dear developers of Nektar++, My name is Ismael El Houas and I am an aeronautical engineer student from the UPC (Universitat Politècnica de Catalunya). Nowadays, I am working on my bachelor's degree final project. For my project, I am working with Nektar++ in order to make a CFD study of a supersonic diamond airfoil, so I am using compressible flow solver. I am considering a symmetrical solution, so I decided to simplify the problem and just study half of the domain. To perform this study, half of the domain, I impose symmetrical boundary conditions on the lower boundary. However, when I study the whole problem the simulation converges to the solution, but when I study just the half of the domain it does not converge. The reported error says: "vacuum is generated". After different tests, I could not find a solution to fix the problem. The boundary conditions I am imposing on the lower boundary for symmetrical solution are: Dirichlet = 0 condition in rhov in order to avoid entrance of fluid from this side, and Neuman = 0 for the other variables (rho,rhou and E). After different tests, I could not find a solution to fix the problem. For this reason, I ask you for some tips in order to be able to find a solution to this problem. Thank you for your attention and congratulations for your work. Kind Regards, Ismael El Houas

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Nektar++ Workshop reminder - 14th-16th June 2017
by Chris Cantwell 12 Apr '17

12 Apr '17

Dear all, Just to remind you that the Nektar++ Workshop for 2017 will take place on the 14th-16th June at Imperial College London, UK. If you have not already registered, you can register at: https://www.eventbrite.co.uk/e/nektar-workshop-2017-tickets-32937018509 Please do get in touch if you have any questions or would be interested in presenting your current work relating to Nektar++. Further details are available at: http://www.nektar.info/community/workshops/nektar-workshop-2017/ We hope to see many of you in June! Chris, David, Mike and Spencer -- Chris Cantwell Imperial College London South Kensington Campus London SW7 2AZ Email: c.cantwell(a)imperial.ac.uk www.imperial.ac.uk/people/c.cantwell

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AeroMoments filter
by F Mellibovsky 04 Apr '17

04 Apr '17

Hi all, I just thought it would be interesting to have a filter that computed moments of forces. It would require the same input parameters as the AeroForces filter plus an extra parameter to state the point with respect to which moments would be calculated, so in principle it should be extremely easy to implement. It's just a thought, but I think it would be valuable to many external aerodynamic applications. Cheers

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