Good day all! This is a relatively specific problem and is mostly addressed to the authors of step-32.
In that example, we scaled the pressure appropriately such that the solution is stable with physical units for viscosity (~10^22 Pa s). However, in my simulation, I would like to solve the Stokes equations for a medium with a large (5 orders +) viscosity contrast. Using a single pressure scaling as in step-32 is stable with viscosity contrasts up to ~ 3 orders. I've tried a sharp viscosity contrast as well as a continuous one where the viscosity contrast across each cell is no more than a factor of a few. Still no reasonable solution! By inspection, it looks like the ( div u = 0 ) condition is not met in the solutions. What is a way to deal with this? In the geophysics literature people have solved problem in a couple of ways, but implementing those fixes would mean almost starting from scratch for my code. Has anyone dealt with large viscosity contrasts in deal.ii? If so, any help is greatly appreciated! Many thanks, Roger _______________________________________________ dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii
