Fix annotations

[HansOlsson]

Avoid using unknown parameters in annotations.

Only one of the changes is somewhat controversial - but having enable evaluating to false on a function input without a default-value simply doesn't work, and I'm not comfortable with adding a default value.

[tobolar]

Only one of the changes is somewhat controversial ...

@HansOlsson You mean input Real epsilon_A in Fluid.Dissipation.Utilities.Functions.PressureLoss.TwoPhase.TwoPhaseDensity, right? I think the input description could be optionally enhanced by something like "relevant for heterogeneous approaches".

But looking in the calculation of rho_mom and rho_kin, the input epsilon_A seems have to be given anyway, so enable annotation makes no sense.

Regarding a default value, IMO this function would be used by an experienced user who knows about necessary inputs for homogenous/heterogenous approaches. So maybe a default value could be acceptable here.

[HansOlsson]

Only one of the changes is somewhat controversial ...

@HansOlsson You mean input Real epsilon_A in Fluid.Dissipation.Utilities.Functions.PressureLoss.TwoPhase.TwoPhaseDensity, right? I think the input description could be optionally enhanced by something like "relevant for heterogeneous approaches".

Yes.
I agree adding that description and possible default value would be possible, but I view that as a further enhancements that can be done later in a separate PR.

[tobolar]

Fine to me.