[FLASH-USERS] About Multispecies Unit

[Klaus Weide]

On Tue, 30 Apr 2019, liu zhigang wrote:

> Dear Flash user,

> I hope to solve a multiphase flow problem using Flash. And there are two 
> spatial regions in my problem, each of which is described by different 
> equations of state (EOS). My question is whether this can be achieved 
> with multispecies unit. 

That depends, mostly on what those EOS are.

If both phases can be described by ideal-gas EOS, then probably yes.
If not, then it becomes more complicated.

> If it is possible, I want to know how to trace 
> the interface between two regions.

 * You declare SPECIES (materials), at least two.

 * You initialize mass fractions for each SPECIES, they can be different 
   in different parts of the domain.

 * FLASH (Hydro unit) will advect the mass fractions, and also 
   occasionally ensure that they still add up to one in each cell.

That's all the tracing you get.

> Thanks for reading! If you have any ideas or suggestions, I'd greatly appreciate the help!

HTH,

Klaus