# Finite volume a posteriori error estimation

I'm wondering what alternatives there are to a grid convergence study to judge solution accuracy for a given grid resolution when doing steady-state RANS simulations on an automatically generated complex unstructured co-located grid (using OpenFOAM). Ideally, such a criterion would lend itself to automatic grid refinement.

• If you are interested in some integral quantities like lift/drag forces, you can use grid adaptation that targets the error in these quantities. This requires solving an adjoint problem and computing cell-level error estimates. Such an approach can also give an estimate of the error in the integral quantities which can be used to judge the convergence of the solution. E.g., search for papers of Venditti and Darmofal for compressible flow case. – cfdlab Sep 7 '17 at 12:10
• @PraveenChandrashekar Any reason you didn't add your comment as an answer? :) – akid Sep 10 '17 at 8:22
• I was not sure if it really answered the question. Hence only a comment. – cfdlab Oct 7 '17 at 3:34