1) Enter the value for total pressure in the Gauge Total Pressure field in the Pressure Inlet dialog box.

2) I suggest to patch hydrogen in the region during initialization and re run the simulation.

Can you please provide more details which include:

1) How you model the phase interaction and heat, mass,reaction in the multiphase panel?

2) Please provide the contours of hydrogen volume fraction and ammonia liquid volume fraction at t=0.

Thank you.