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Ideas for identifying the ‘inlet’ boundary region

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› Forums › OpenLB › General Topics › Ideas for identifying the ‘inlet’ boundary region

Viewing 5 posts - 1 through 5 (of 5 total)
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  • April 23, 2021 at 9:38 pm #5619
    manash.pb
    Participant

    Hi all,
    I am simulating airflow through a human nose. The geometry is taken from an STL file and I want to identify and set the nostrils as the inlet plane. As the structure of the nostril opening is not a proper geometrical shape (not a circle or ellipse and both the nostrils are very closely placed), I am having difficulty in identifying the regions through an IndicatorFunction. Is there a smarter and better way to define the boundary regions? For ex, maybe a list of coordinates may be read from a file, which corresponds to the face centers of the STL triangles making up the plane? Any suggestions will be helpful!
    Thanks and Regards,
    Manash

    April 24, 2021 at 3:53 pm #5620
    mathias
    Keymaster

    Dear Manash,

    you can work with intersections of geometry primitives (indicators) like cylinders, cuboids, etc. with the actualy generated voxel mesh by and stl-file or you may extend the region growing apporach (https://www.openlb.net/DoxyGen/html/d3/d2a/classolb_1_1BlockGeometryStructure3D.html#aa1a30cd27881b163d0486556769fcc70) to the superGeometry implementation, which is only available for blockGeometries at the momenent.

    Best
    Mathias

    April 25, 2021 at 7:22 pm #5621
    manash.pb
    Participant

    Hi,
    Thanks for your reply. I have been trying with different geometries, but still not successful till now. Regarding the region growing, how can I get the iX, iY, iZ for the seed point (I guess these are the lattice coordinate values). How can I access the lattice coordinate values corresponding to the physical coordinates (which I can get from Paraview for the boundary face)?

    Manash

    April 26, 2021 at 2:38 pm #5628
    mathias
    Keymaster

    Dear Manash,

    You need to write a new method which starts the reagion growing for any point within an idicator, lets say asphere, which intersections with a particular material number, e.g. 2, to start the algirthm. But keep in mind that you need to program the parallel region growing algorithm first. Within a colaboration we could help you further but that needs some efford.

    Best
    Mathias

    April 28, 2021 at 2:35 pm #5632
    manash.pb
    Participant

    Hi,
    Thanks for the reply. I guess I will try to work with the geometry primitives for now. My knowledge of OpenLB (and LBM methods in general) is still a bit sketchy. I would like to spend some time on improving my understanding (of whatever is available in OpenLB) for now. Maybe, at a later phase, I will think about writing methods of my own. I will also look towards attending a OpenLB summer school training in the future to learn better.

    Regards,
    Manash

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