Dear thanks for your replay.nI made the viscous model to inviscid since I do not know exactly the flow behaviour as I only have flow input in m3/s which I converted to a viscosity using the flow-Surface-viscosity relation.nI had 2 issues.nHad an error statement floating point exception #fnthe length of the output is far away than I am expecting since I have a flow of 60m3/s result in a length less than 10 mm n