Midsurface plane deviation

Pichaya1_K
Pichaya1_K Altair Community Member

Dear All,

I am encountering an issue in Altair HyperMesh 2024.1 during midsurface generation for shell element simulation. After generating the midsurface, there is a deviation of about 0.00225 mm in the Y-axis, resulting in slightly tilted due to the deviation when trying to stitch it to the adjacent beams (purple).

I have already checked the dimensions of the original 3D solid model, and there is no deviation in any axis. The issue only occurs during midsurface generation.

How can I fix this deviation and ensure accurate midsurfacing for proper stitching?

Regards,

Pichaya K.

Answers

  • Fred_Juras
    Fred_Juras
    Altair Employee

    Hi Pichaya,

    According to your screenshots, it looks like you're measuring and comparing the length of the initial solid vs the midsurface. The midsurface is created inside the volume and therefore it is shorten than the initial part. Does it make sense?

    Regards,
    Fred.

  • Pichaya1_K
    Pichaya1_K Altair Community Member

    Dear Fred,

    Sorry for my confusing attached pictures. I intended to show that when I measure the length in my initial 3D model. There is no plane deviation. But when i extract midsurface from the same 3D i mentioned. There is a surface deviation in Dz direction for 0.00225 mm. (*edited in my last comment i said it deviates in y-axis which is wrong) as shown on the second picture.

    Best regards,

    Pichaya

  • Fred_Juras
    Fred_Juras
    Altair Employee

    Oh yes indeed.
    What about the top surface? Is there any existing deviation on this one that can explain the final deviation? By default, the 'offset' extraction method tries to put a fixed point at the middle of the two initial points from the solid geometry.

    If it's not the case, I can't tell. There's no tool or option to control such tiny deviation.

    Regards,
    Fred.

  • Pichaya1_K
    Pichaya1_K Altair Community Member

    Dear Fred,


    The top surface has also no deviation. I decided to neglect this small deviation and hope my mesh will be fine.

    Thank you for your comment.


    Pichaya