Hi Chris,

Seems to simulate fine anyway except that the fluid is at the absolute zero temperature in valve.
You have make your own closed tank.
Why not use closed tank object of Modelica's Fluid  library ?

I am going to study your script, it's very interesting to understand how to use/create mixture medium.


/Bruno

Sorry I can help too  much, but I would not worry about the violations of  limits along initialization. As the connection between elements is done using enthalpy, and not temperature, the port_a_T and port_b_T values are only informative in this case. As they are calculated from state_a and state_b, its initialization will come from pressure, enthalpy and composition at the ports, but it is difficult to follow the origin. The easy way is to change your difinition of Temperature in the Medium to: Temperature(start = T_default, min=0.0). Of course you solve nothing with this, only not to have warning, but the fact is that there is nothing to solve.
For the initialization of X[2] at -500 at the valve and the pump (interesting that not at your tank) I do not see the reason.

Hi!
Thanks for the replies. From other tools (E+) I am used to worry about warning but in case I think it is not a problem they appear. Maybe someone can still comment on the warning concerning the concentration.
Cheers
Christian