Hi JG I can answer your third question: 3. Pointwise has a writer for the native format of PyFR However, that writer does not support periodic b.c. at the moment. The workaround is to use the gmsh writer. So create your mesh in Pointwise making sure the periodic surfaces have the same mesh (1to1 matching). Then select as solver gmsh and assign each periodic surface a name using the convention 'periodic_ntrasfor_side', where ntransfor is an integer defining the periodic transformation (there can be more than one) and side is either l or r. So for instance, you could have the two periodic surfaces named 'periodic_0_l' and 'periodic_0_r'. Note that in the PyFR .ini file periodic surfaces should no be specified; that information is inferred from the mesh.
Also, for high angle of attack simulations, you may find this paper useful: https://arc.aiaa.org/doi/10.2514/1.J055304 Best Giorgio On Tuesday, September 3, 2019 at 3:52:50 PM UTC+1, JG wrote: > > Dear PyFR developers and users, > > I have successfully reproduced the LES simulation of the flow around a > sd7003 airfoil presented in the paper (On the utility of GPU accelerated > high-order methods for unsteady flow simulations: A comparison with > industry-standard tools, 2017 JCP). The results are quite good. > > Now, I want to perform LES of flow around a NACA0015 airfoil with angle of > attack near stall angle and Reynolds number of around 60,000. The first > difficulty encountered is the mesh generation. I have the following > problems: > > 1. In the PyFR user guide, the free software Gmsh is used to generate > mesh. As seen in the above JCP paper by the developers, the mesh used in > LES of flow past airfoil is complex. The mesh is refined near the airfoil > and in the rectangular wake region, and then quickly coarsened outside > these regions. So, is there any example script that can be read into Gmsh > to generate such a complex mesh for a LES simulation or any guide for > complex mesh generation? > > 2. For a LES simulation, the grid resolution (dx, dy, dz) in streamwise, > wall-normal and spanwise direction respectively must satisfy certain > criterion. According to the above JCP paper, y+ in the first layer of mesh > near wall is around 0.4. So, what is the grid spacing in streamwise (dx) > and spanwise (dz) direction if the Reynolds number is around say 60,000? > > 3. Pointwise17.3R4 can generate mesh for PyFR. However, its seems that in > Pointwise, one cannot specify periodic boundary conditions and there is no > option for periodic BC. So, how can we impose the periodic BC when > pointwise is used. > > It will be greatly appreciated if anyone can help answer the above > questions or give some suggestion. > > Best regards, > > Jianguo > > -- You received this message because you are subscribed to the Google Groups "PyFR Mailing List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/pyfrmailinglist/49dc0e52-1219-4d14-b44a-bc172c88adad%40googlegroups.com.
