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Local Material/Element Coordinate System Question for Contoured/Elliptical Meshes

Creator
Creator

Hi all,

 

I am analyzing an ellipctical composite structure in FEMAP, I need to have local coordinate element coordinate systems that follow the contour of the part so I can interpret my results. From what I remember in NX Simcenter there is a way to create local element coordinate systems following the contour of a part quite easily with just a few clicks, but I am not sure how to do this in FEMAP. Right now, the only way I know to solve this problem is an imperfect solution of creating a bunch of manual cylindrical coordinate systems to use, which would be difficult and timeconsuming(Not to mention not completely correct).

 

Does anyone know of a better way to do this? I am imagining a function where you define a curve or the surface and then FEMAP auto-generates a coordinate system for each individual element, but nothing like that may exist.

4 REPLIES
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Re: Local Material/Element Coordinate System Question for Contoured/Elliptical Meshes

Siemens Phenom Siemens Phenom
Siemens Phenom

It sounds like you have underlying geometry that you would like to align the element material direction with either the U or V direction of these surfaces.  This API will prompt you for surfaces, and then a Yes/No Question that corresponds to U or V.  It then updates the Material Angle of every 3, 4, 6, or 8 noded shell attached to those surfaces to those U or V directions -

 

The HTML Clipboard

Sub Main
    Dim App As femap.model
    Set App = feFemap()

    Dim suSet As femap.Set
    Set suSet = App.feSet

    Dim alignU As Boolean

    Dim feSurf As femap.Surface
    Set feSurf = App.feSurface

    Dim elSet As femap.Set
    Set elSet = App.feSet

    Dim feElem As femap.Elem
    Set feElem = App.feElem

    Dim elCG As Variant

    Dim uVec As Variant
    Dim vVec As Variant

    Dim u As Double
    Dim v As Double

    If suSet.Select( FT_SURFACE, True, "Pick Surface(s) to Align Attached Shell Material Angles") = FE_OK Then

        If MsgBox( "Yes for U Direction, No for V", vbYesNo) = vbYes Then
            alignU = True
        Else
            alignU = False
        End If

        While feSurf.NextInSet( suSet.ID ) = FE_OK
            elSet.Clear
            elSet.AddRule( feSurf.ID, FGD_ELEM_ATSURFACE)
            feElem.Reset
            While feElem.NextInSet( elSet.ID) = FE_OK
                If feElem.topology = FTO_TRIA3 Or feElem.topology = FTO_TRIA6 Or feElem.topology = FTO_QUAD4 Or feElem.topology = FTO_QUAD8 Then
                    If feElem.GetCentroid( elCG ) = FE_OK Then
                        If feSurf.XYZToParam( elCG, u, v ) = FE_OK Then
                            If feSurf.Tangents( u, v, uVec, vVec ) = FE_OK Then
                                If alignU Then
                                    App.feModifyMaterialAngle( -feElem.ID, 1, uVec, 0, 0, 0.0 )
                                Else
                                    App.feModifyMaterialAngle( -feElem.ID, 1, vVec, 0, 0, 0.0 )
                                End If
                            End If
                        End If
                    End If
                End If
            Wend
        Wend
    End If
End Sub

Re: Local Material/Element Coordinate System Question for Contoured/Elliptical Meshes

Creator
Creator

Thanks for the reply. Yes that is exactly what I am trying to do and your API would be perfect if it weren't for the fact that I created my brick elements from a swept set of plane elements, so they are not attached to any surfaces. 

Re: Local Material/Element Coordinate System Question for Contoured/Elliptical Meshes

Valued Contributor
Valued Contributor

Hi,

you can assign material direction to elements directly  without associativity with surfaces.

Then simply transform results into material direction to get additional output vectors.

Additional_outVec_Material_dir_.pngResults for elements after transformationDisplay_Material_dir_.pngShow material directionsMaterial_dir_reansform.pngAssign material direction to elements

Tadeusz

Re: Local Material/Element Coordinate System Question for Contoured/Elliptical Meshes

Creator
Creator

Yes I am aware you can do that. No coordinate system I could assign to the material would accurately define the elliptical shape though, so I would have to manually create coordinate systems for each row of elements which would be time consuming and I was trying to see if there was an easier way. Also, your method only works for plate elements and I am working with bricks. I may rebuild my part based off surfaces and see if that API works.