Turbine with Constant Power Output in Dymola

Question

Currently, I'm working on designing a turbine with a steady power output that will draw air from a storage tank ( 50 bar, 500C). With constant power generation planned, the mass intake should change in response to the power. I require the model in calculating the mass flow rate that is drawn from the storage container. Could you please assist me?

    model TestTurbine
  Turbine turbine(redeclare package Medium = CAES.DryAirNasa)
    annotation (Placement(transformation(extent={{-12,-10},{8,10}})));
  Modelica.Fluid.Sources.Boundary_pT boundary(
    redeclare package Medium = CAES.DryAirNasa,
    p=101325,
    T=298.15,
    nPorts=1) annotation (Placement(transformation(extent={{16,-54},{36,-34}})));
  Volumes.Volume volume(
    redeclare package Medium = Modelica.Media.Air.DryAirNasa,
    V=20,
    p_start=5000000,
    T_start=773.15)
    annotation (Placement(transformation(extent={{-84,-4},{-64,16}})));
equation 
  connect(boundary.ports[1], turbine.port_b) annotation (Line(points={{36,-44},{
          40,-44},{40,0},{8,0}}, color={0,127,255}));
  connect(volume.In, turbine.port_a) annotation (Line(points={{-83.2,6},{-88,6},
          {-88,-8},{-18,-8},{-18,-0.2},{-12,-0.2}}, color={0,127,255}));
  annotation (Icon(coordinateSystem(preserveAspectRatio=false)), Diagram(
        coordinateSystem(preserveAspectRatio=false)));
end TestTurbine;