inverse iteration in region 3: (d,T) = f(p,h)
function dtofph3 extends Modelica.Icons.Function; input SI.Pressure p "pressure"; input SI.SpecificEnthalpy h "specific enthalpy"; input SI.Pressure delp "iteration accuracy"; input SI.SpecificEnthalpy delh "iteration accuracy"; output SI.Density d "density"; output SI.Temperature T "temperature (K)"; output Integer error "error flag: iteration failed if different from 0"; end dtofph3;