Different numerical solutions can basically not be compared and it is therefore actually quite expected that the results will differ between the two types of models – even though the model schematisation is replicated such that the rectangular grid in the MIKE 21 SG model and the mesh in MIKE21 FM are identical. MIKE 21 SG is a grid-based Finite Difference method whereas the FM-model uses a cell-centred Finite Volume method. Why is it so? Which version is more correct? Answer:įirst of all, the main thing to put in focus here is that the two simulations will use two different numerical solution methods when comparing the rectangular single (or ‘classic’) grid (SG) to the Flexible Mesh (FM) version of MIKE 21.
I applied similar parameters, however the results differ. MIKE FLOOD: I run MIKE FLOOD successively with MIKE 21 rectangular grid and flexible mesh versions. Please do not hesitate to e-mail us if you have questions and/or answers yourself:
