Hello, I'm trying to run fluid simulation where 2 fluids (one of them being blood) come in through separate channels and interact.  However, when I add blood and, let's say water, into my boundary conditions, I have no option for substance concentration settings.  In fact, it doesn't recognize that the blood is there at all even though I added it to the simulation.  If I use two liquids that are both Newtonian, the simulation runs fine.  Is there a way to run blood through this simulation at all?  Thanks for the help.