So I was looking at the examples for which artificial viscosity were used in different cases and I saw that sometimes the same artificial viscosity was used for both water and air. I understand that the artificial viscosity scheme is not meant to be a replacement for physical viscosity but shouldn't there be some kind of difference in artificial viscosity anyways since the viscosity of air is 12 times the viscosity of water? (at 20 degrees celsius, according to Engineering Toolbox website)
Also by looking at the XML documentation I see for the artificial viscosity that:
So when we are using the artificial viscosity scheme we control only the constant which is multiplied on the dynamic viscosity divided by the density. I understand that the "bar" operation is average sound and density of a + b, but how it µ_ab calculated or defined?
I am also a bit unsure about the "ViscoBoundFactor", since I am making a simulation of a tank like this:
Blue = water, gray = air
By using a visco bound factor I am able to control the "roughness" of the boundary surface?
To sum it up:
1) Should I use same alpha for water and air?
2) How is the µ_ab term defined or calculated?
3) Is it correct to say that the visco bound factor controls the "roughness" of a boundary?
Sorry for my long question, but I just need to make sure that I understand the settings and options in DualSPHysics.
Thanks you for reading.