Why is the total temperature equal to the critical temperature using the Redlich Kwong equation of state at conditions T>Tc and p>pc?
When running the the Redlich Kwong equation of state or a user supplied RGP file, the flow solver clips two dimensional property tables at the spinodal or saturation curves per default.
Below the critical point, the liquid (p < pc & T < Tsat) and vapor (p < pc & T > Tsat & T < Tc) regions are separated by the saturation curve. Above the critical point there is no difference between the liquid and the vapor states. This region is called supercritical region (p > pc or T > Tc).
When the flow solver needs to interpolate a value of Phi at a given temperature T and pressure p, there are these three possible regions: liquid, vapor or supercritical. For any of these regions there are three possible table interpolation options available by setting the expert parameter:
prop interp option = 1, 2 (default), or 3
1 ` the flow solver does not use saturation curve clipping
2 ` the flow solver always uses saturation clipping assuming that saturation data has been extended along the critical isotherm
3 ` the flow solver uses no saturation clipping above the critical pressure.