I'm trying to create a fluid simulation, where I'm working with a barotropic equation of state for simplicity. Assuming I have some fluid with a barotropic equation of state, e.g. a very simple atmosphere:
$$p = \rho \cdot A$$ Where $p$ is the pressure in $\rm kg/m/s^2$, $\rho$ is the density in $\rm kg/m^3$ and $A$ is some proportionality constant in ($\rm m^2/s^2$).
For air, I can find a value for $A$ by dividing pressure by density at sea-level, for example, but within this approximation, how would I find values that represent oil or water? I've looked at a few papers on atmospheric simulations, but none of them really explicitly deal with the value of $A$.
I've been somewhat successful in creating a simulation where "water" floats on "oil" (basically 2 fluids with a different (unrealistic?) values of $A$), but I'm trying to recreate this with more appropriate values.