Reply To: Pressure outlet boundary condition

[Gennadii]

Hi Rob,

Thank you for your response.

Could you please explain (or point me to relevant resources) how it is possible for the "outside" pressure to be 1 atm while the outlet pressure is 2 atm? This suggests that some form of transition must occur between the outlet and the "outside" region.

For example, in the case of temperature, the outlet boundary condition typically imposes a zero flux, meaning there is no temperature gradient across the outlet, so the "outside" temperature becomes equal to the outlet temperature. How does this work for pressure? How is the step transition handled, and how does it influence the outlet pressure?

Thank you in advance.