Process mode for the U3 example simulation

The purpose of Process mode is to perform a steam balance. Some important aspects include:

• We specify the steam flow at each steam consumer, which we model as Sinks in the simulation. To make this specification, we calculate the outlet flow ratios (OutRatio) of the Junction models and the total steam generation.

• We combine the mechanical power for both steam turbines into a single shaft so that you can specify a total power from both turbines by using the Power_net variable in the shaft if desired.

• We use a desuperheater model (that is, a Desup model) to calculate the boiler feed water required to maintain 18°C (10°F) of superheat after the high pressure to medium pressure letdown.

• We size the high pressure pipes to provide the required pressure drop. Select a pipe size so that the diameter margin (D_margin) is positive for each pipe while maintaining steam velocities less than 70 m/s (200 ft/s). You should perform this step in Process mode before transitioning the simulation to Fluid Flow mode.