Hi, everyone

I have project about the gas flow mode on the low-pressure equipment, I encounter some difficulties about gas expansion on the low-pressure device.

The gas (2l/min) will inject into equipment, Under normal temperature and pressure. the pressure and temperature inside the equipment are 5 kPa and 1000K, respectively.

The question is ...When i set the boundary conditions (inlet flow rate), which one should i set: 2l/min with normal temperature and pressure or the flow rate after EXPANSION with 5kPa and 1000K?

another question is how should i set the initial condition when i use the guide? 

Thank you!! 

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