A colleague sent me a Tecplot *.plt file consisting of the CVD results for a NACA0012 2D simulation. When I take a slice using the slice filter and save as csv data, I end up with a ~29000 row file of velocities. The mesh is only ~2000 in the slice direction. Plots of the velocities look fine. However, when I differentiate the data twice to look at the viscous regions, I end up with spikes all trough the data instead of a smooth curve. I think ParaView is pulling multiple data points from each cell and then trying to differentiate the cell values which blow up. Any ideas on how to pull data so the derivative do not blow up?
Please share your data.