PotentialFoam Mesh Convergence Trouble
 

I've been working on learning OpenFOAM for the last several months. I'm an Aerospace Engineering PhD student, but this is basically my first time using CFD. I'm using Openfoam 2312 on a Ubuntu system. So far I have run the tutorial cases for potential flow over a cylinder, as well as the turbulent flow over a NACA 0012 airfoil. I haven't had any issues running or viewing the results from those cases.


I'm setting up a 2-D potential flow case with a NACA 0012 airfoil, and I'm planning to use these results as a reference case for my research. I'm using blockMesh to create the mesh, and I've used this source for inspiration. http://https://www.phanquocthien.org...ckmesh/airfoil. I've uploaded my blockMeshDict file Attachment 99322. All of my other system folder files are the same as the potential flow cylinder case.


My mesh is setup as a rectangular volume, like the potential flow cylinder. I've attached pictures of my U Attachment 99324 and P Attachment 99323 boundary conditions. I'm using the pressureInletOutletVelocity BC to facilitate changing the angle of attack of my airfoil at a later date.



I'm able to run my case, and it seems to converge based off of the log.potentialFoam. When I look at my case in ParaView, everything seems fine. I moved on to my mesh convergence study, which is where I ran into issues. When I performed my mesh convergence study, my CL and CD values diverge. This indicates that I have a problem somewhere.



I did notice that as my mesh got finer, the solution in ParaView looked less realistic. All of the flow looks uniform, except for what looks like a discontinuity at the leading edge of the airfoil. I've attached pictures to show what I mean Attachment 99326 Attachment 99325. I'm not sure where to begin looking for this problem, but I'm guessing that it is related to my BC or my mesh. I've googled and looked through multiple other forum posts, but I haven't found anything related to my problem. There don't seem to be many posts about 2-D potential flow simulations.