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Validating Lid-driven cavity with High RE number

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Viewing 5 posts - 16 through 20 (of 20 total)
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  • #9152
    Adrian
    Keymaster

    Did you follow my other suggestion?.

    The relaxation time is also very critical for the time to solution.

    #9153
    thanhphatvt
    Participant

    Dear Adrian,
    I checked the cavity3dBenchmarks: the MLUPs is 252.7
    Our simulation: the MLUPs is 216.3
    Thanks

    #9182
    thanhphatvt
    Participant

    Dear Adrian and Mathias,
    With the resolution is over 400, the results showed the good agreement with the references.
    Thank for your help!

    #9436
    arpiruk
    Participant

    Hi thanhphatvt,

    I came here to do a similar thing you wanted to do. I’ll guess I can help you out a bit.

    I did a DNS with my fourth-order FVM code using more ore less the same grid as the reference. I guess you use Lereiche’s result. I can tell you that for RE18K (mean RE=15K), you need a very long .. long .. long .. long integration time. By long, I mean the sampling time > 1500 D/U_L , for D being cavity width(&depth) and U_L being lid’s velocity. Also, Lereiche result in his DNS paper is about 700 D/U_L for RE15K, and it is only 500D/U_L for Re10K. So keep that in mind.

    There is a large scale movement which is not averaged out easily. For RE=10K, you’ll be fine with about 1,000 D/U_L. But, a big but, the difference btw a statistics of one 1000 samples (sampling every time unit), and another set of the 1000 can be a bout 3-5%.

    Do not expect a perfect collapsing plot like in turbulent channel flow.

    #9437
    thanhphatvt
    Participant

    Dear arpiuk,
    Thank you so much! Now my results have the 5-7% of discrepancy. I think it’s ok now. I’m trying to simulate the cough flow with the aerosol particle with open LB.
    Thanks

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