Continuity is a property is defined in FCSys resistivity to axial compression or material storage during transport.
function zeta
extends Modelica.Icons.Function;
input Q.TemperatureAbsolute T = 298.15*U.K "Temperature" annotation(
Dialog(__Dymola_label = "<html><i>T</i></html>"));
input Q.VolumeSpecific v = 298.15*U.K/p0 "Specific volume" annotation(
Dialog(__Dymola_label = "<html><i>v</i></html>"));
output Q.Continuity zeta "Continuity" annotation(
Dialog(__Dymola_label = "<html>ζ</html>"));
end zeta;