Issue in simulation of open channel flow with high viscosity fluid
 

Hi ,

I am trying to simulate the flow of a high viscous fluid (about 1-10 Pa-s) in an open channel. I made the model and ran it for the case of water at first and the software was able to converge the simulation easily. However, by increasing the dynamic viscosity to the real value for my fluid which is about 1-10 Pa-s, it can not converge the model for some reason. Anyone had this problem before ? I really need to know what I can do for high viscous fluid simulation in open channels. Thanks a lot

I think this is because you are using an explicit scheme for time advancement.
You can try to use an implicit time scheme.

You have to give more information. How do you know it's not converging?