Step 1-C

Determine the maxim fluid flux (Gmax) for the nozzle before sizing the pipe.  The equation used for finding Gmax for the nozzle, and the Mach II input for the "Main", and "HEM"  Basic Data tab are shown below the input screens.

Select, "Rigorous HEM", for direct integration method, API, Design mode, Equilibrium, and no slip for standard HEM design.  The Calculation type can be ignored since this will only be a calculation for Gmax not a vent sizing calculations.

For the HEM screen input his physical properties for State A, State B, and State C.  Select, "use 3pt", select, "enter enthalpy data", to calculate the mass fractions at points B, and C.  At point A, the mass fraction is zero (0.0).  This value is actually input from his Basic data, "Vessel" tab, not shown.  Larry uses entropy data instead of enthalpy data because based on research it has been determined that entropy data gives the best results but enthalpy data is easier to find.