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Time Dependent Solver for Free Molecular Flow

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Good morning,

I am new to this program, still trying to learn. My current goal is to model a pore with a single opening and see the time evolution of profiles of a free molecular flow.

I have found an existing model from the library, vacuum capillary, and decided to make a few changes from there. 1) I have added an additional time dependent study 2) I have replaced the vacuum with a wall

For each step, I have encountered different issues.

After implementing time dependent study, I see no change in flux/density/pressure over time. Even for a smaller time range, it did not make any difference.

After removing vacuum boundary condition and have (previously overridden) wall boundary condition restored, I see a flat profile over the entire region and that is for both stationary and time dependent studies.

Clearly, I must be doing something wrong here. I was wondering if anyone could guide me somewhere in the right direction, maybe another thread or an application gallery. Thank you.

Sincerly, Dustin


0 Replies Last Post 28 mai 2020, 11:07 UTC−4
COMSOL Moderator

Hello Dustin Chung

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