Incomprehensible simulation results

[D. J. LEE]

1. Simulation conditions

(1) 49-story building above ground
(2) Height: 160m
(3) Relative elevation of the paths: same (1m)
(3) ambient temperature: -10 degrees Celsius
(4) Simulation Method: Steady

2. Simulation results

In the layers above the neutral pressure plane (NPP), the direction of positive differential pressure (dP) measured in each path of the shaft wall is the same, while in the layers below the NPP, the direction of the positive dP in each path is different.
Please refer to the attached picture file.

3. Questions

I understand that even if there are multiple flow paths at the boundary between two adjacent zones, the differential pressure measured in each path should be the same once the airflow reaches a steady state.

I can't figure out why the dP measured in each path differs.
Is there anything else I need to consider to get the right results?

Please know that although I got the original project file from the author, I am posting the picture file because I cannot leak the data.

I appreciate your sooner and kind support very much in advance.

D. J. Lee

[William Dols]

D. J. Lee,

Please look at this post related to the issue you address for another user.

https://groups.google.com/a/list.nist.gov/g/contam/c/_cJ6NrJ_Nx0/m/6mbZatXkAAAJ
Open the PRJ with a text editor, e.g., NotePad++ and check the Junction section of the file.
Make sure the values in the "l#" column indicate the correct level of the PRJ for each Junction/Terminal.

Please let us know if this is the issue.

- Stuart