Sublimation pressure of water below the triple point temperature is computed from temperature.
Source: W Wagner, A Saul, A Pruss: "International equations for the pressure along the melting and along the sublimation curve of ordinary water substance", equation 3.5
function sublimationPressureIce extends Modelica.Icons.Function; input SI.Temperature Tsat "Sublimation temperature"; output SI.AbsolutePressure psat "Sublimation pressure"; end sublimationPressureIce;