Good afternoon,

I'm modeling thermo-fluid systems.

This vectorial equation "produces" an algebraic loop:

{Dn, Hn} = Thermo.DnHn(P = P, T = T, Xn = Xn);

The thermo functions are highly dependent on temperature.

Everytime that the algebraic loop is solved, a lot of iterations are needed:

############ Solve nonlinear system 160 at time 1 ############
initial variable values:
[ 1]                       volume.P  =        99500.023         nom =           100000
[ 2]                       volume.T  =        682.77722         nom =              300
Solution status: SOLVED
 number of iterations           : 1810
 number of function evaluations : 6470
 number of jacobian evaluations : 1810
solution values:
[ 1]                       volume.P  =        99500.023
[ 2]                       volume.T  =        682.77722

Even when the initial values are really close to the solution, a lot of iterations are needed. Why is this happening?

Thanks in advance