[_dsteven95]

Hello,

I am a student and I am currently trying to solve a problem for compressible flow in a converging-diverging nozzle. I cannot achieve convergence for one of the sets of boundary conditions I have to solve for and in order to do this the project description says we should add artificial viscosity in order to do this.

I have spent some amount of time playing around with the settings and searching online but I still can't find out how to do this.. can anyone help?
Thanks

[LuckyTran]

I think they mean to just adjust and arbitrarily increase the viscosity (change the material property). Hard to say though, since we didn't write your project description. Maybe you should ask the project owner?

[_dsteven95]

Thanks, yeah I thought that might be a possibility.. However in the problem it states we should use the ideal gas treatment so when this is selected there is no option to change the viscosity under the materials control panel.

The person who wrote the project is reluctant to give us help as he wants us to do it by ourselves unfortunately!

[LuckyTran]

There is no ideal gas option for viscosity. And viscosity is not affected by the ideal gas EOS (viscosity is a transport property).

[shahrooz.omd]

Artificial viscosity method needs to be implemented in the solver, it does not mean to increase viscosity arbitrarily. Doing it by yourself means you solved the problem for another fluid.

[LuckyTran]

Originally Posted by shahrooz.omd

Artificial viscosity method needs to be implemented in the solver, it does not mean to increase viscosity arbitrarily. Doing it buy yourself means you solved the problem for another fluid.

OHHHHHHHH!!!!! I wasn't paying attention to the fact that we're talking about compressible flow simulation with shockwaves. =(

I don't think that method is implemented in Fluent though.