I have done some NS analysis and now want to do some post-processing using my results, I want to calculate my lift and drag over a certain part of the boundary (i.e its a surface integral). I have my functional defined and I use following line to calculate the drag
c_d = Integrate(cf=Drag(u_h,p0), mesh=mesh, VOL_or_BND=BND, definedon=mesh.Boundaries("cyl"), order=1)
but i get the error
Anyone knows what this is?
Thanks in advance.