Preprocessing

Preprocessing

Bonded contact for a two layered beam – ANSYS Mechanical APDL commands

    • simonfur1
      Subscriber

      Dear community,


      Ive been hitting the wall lately while performing something so simple as applying contact between to interfacing volume meshes (that simulate a CF-layer and a thin piezo electrical layer).

      It will not bond. Running a modal analysis make the parts split in all directions.


      I try to avoid using nummrg as I will make the piezo layer much thinner, and apply way more elements to it, making the element amount very different from the top layer to the bottom one. ( Ideal situation for using contact elements)

      Please see my attached code. Do anyone have any good ideas?

    • peteroznewman
      Subscriber

      I have copied your code into this post because ANSYS staff are not permitted to open attachments.




      /CLEAR
      /PREP7
      /UIS,MSGPOP,3

      /title, Harmonic analysis of a carbon-fibre layered beam with ZnO
      !
      !
      !Element Types !
      !
      !
      !Composite layer element type
      ET,1,SOLID185,,,1 !Remember to give same thickness in secdata as in the given volume
      !Glass layer element type
      ET,2,SOLID185,,,1 !Remember to give same thickness in secdata as in the given volume
      !Piezoelectric Element
      ET,3,solid226,1001
      !Contact element:
      ET,4,CONTA174
      !Resistor Element
      ET,5,CIRCU94,0
      !Target element
      ET,6,TARGE170

      ! ELement division:
      !attribute for volume (Warning, picked lines cant be one same height)!
      *set,plmesh,10 ! mesh for plate=number of segments
      *set,pzmesh,20 ! mesh for pzt=number of segments. Set to the same to avoid additional contact meshing (difference is minimal)
      *set,meshthc,1 !no of element through thickness of piezo
      tccf=0.000120 ! cf layer thickness
      tcglass=0.00012 ! cf layer thickness
      tZnO=1e-4
      BeamW = 0.032
      BeamL = 0.239
      CFL1=0.119
      GFL=0.151
      CFL2=0.154
      ! Top electrode size:
      Ell=0.1
      Elw=0.02
      ! Offset from clamped edge:
      GOff=0.015
      CF2off=0.085

      !Piezoelectrical lyers offset:
      OffsetX1=0
      OffsetX2=0.120

      !
      !
      !Material Properties !
      !
      !
      !CF Material Properties
      MP,DENS,1,1100 ! From measurment of acutal beam
      MP,EX,1,45.01e9 !Elastic modulus, x-direction
      MP,EY,1,45.01e9 !Elastic modulus, y-direction
      MP,EZ,1,20e9 !Elastic modulus, z-direction
      MP,PRXY,1,0.35 !Major poisson's ratio, x-y plane
      MP,PRYZ,1,0.2 !Major poisson's ratio, y-z plane
      MP,PRXZ,1,0.35 !Major poisson's ratio, x-z plane
      MP,GXY,1,2.892e9 !Shear modulus, x-y plane
      MP,GYZ,1,2e9 !Shear modulus, y-z plane
      MP,GXZ,1,2e9 !Shear modulus, x-z plane

      !Glass Material Properties
      MP,DENS,2,1500 ! From measurment of acutal beam
      MP,EX,2,22.99e9 !Elastic modulus, x-direction
      MP,EY,2,22.99e9 !Elastic modulus, y-direction
      MP,EZ,2,5e9 !Elastic modulus, z-direction
      MP,PRXY,2,0.3 !Major poisson's ratio, x-y plane
      MP,PRYZ,2,0.2 !Major poisson's ratio, y-z plane
      MP,PRXZ,2,0.3 !Major poisson's ratio, x-z plane
      MP,GXY,2,2.2627e9 !Shear modulus, x-y plane
      MP,GYZ,2,1e9 !Shear modulus, y-z plane
      MP,GXZ,2,1e9 !Shear modulus, x-z plane

      !! Piezo material properties
      MP,DENS,3,1160 !from resin epoxy. Should be modified when real speciments are prepared
      ! Anisotropic properties given as resin epoxy, since crystals do hold very little load individually (approximation):
      MP,EX,3,3780e6 !3780e6, this is resin epoxy. Use however PZT for comparison
      MP,PRXY,3,0.35
      MP,GXY,3,1400e6 !From resin epoxy

      ! See material properties and lirarature overview to see where this is from
      MP,PERx,3,877.6
      MP,PERy,3,877.6
      MP,PERZ,3,1006.3

      TB,PIEZ,3,,,0
      TBMODIF,1,1 TBMODIF,1,2 TBMODIF,1,3,-0.62 !e13
      TBMODIF,2,1 TBMODIF,2,2 TBMODIF,2,3, !e23
      TBMODIF,3,1 TBMODIF,3,2 TBMODIF,3,3,0.96 !e33
      TBMODIF,4,1 TBMODIF,4,2, !e42
      TBMODIF,4,3 TBMODIF,5,1,-0.37 !e51
      TBMODIF,5,2 TBMODIF,5,3 TBMODIF,6,1 TBMODIF,6,2 TBMODIF,6,3
      !
      !
      !Geometry Dimensions !
      !
      !
      !Composite layer 1
      materid=1 !material id
      ang1=0 !angel of layer in degrees
      SECTYPE,1,shell,,layer1 !define which element type
      SECDATA,tccf,materid,ang1 !define thikncess and angle

      !Glass layer
      materid=2 !material id
      ang2=0 !angel of layer in degrees
      SECTYPE,2,shell,,layer2 !define which element type
      SECDATA,tcglass,materid,ang2 !define thikncess and angle

      !
      !
      !Reserved Nodes for Circuit !
      !
      !
      !circuit dimension
      cirdim = 0.02
      n,1,-4*cirdim,0,3*cirdim
      n,2,-4*cirdim,0,cirdim
      n,3,BeamL+4*cirdim,0,3*cirdim
      n,4,BeamL+4*cirdim,0,cirdim
      !
      !
      !FEM Domain Geometries !
      !
      !
      !Create Beam, Epoxy and Piezoelement nr 1 (start on top and go downward)
      BLOCK,0,CFL1,-BeamW/2.0,BeamW/2.0,0,tccf ! CF layer 1
      BLOCK,0,CFL1,-BeamW/2.0,BeamW/2.0,0,-tZnO !Piezo Layer 1



      !
      !
      !Mesh !
      !
      !
      ! Corner line meshing of all SOLID185 elements (cant be divided in thickness)
      LSEL,S,LINE,,9,12,1 !SELECT CORNER LINES OF composite LAYER 1
      LESIZE,ALL,,,1 !# OF ELEMENT DIVISION

      ! Composites layers length/width meshing:
      LSEL,S,LINE,,1,3,2 !SELECT SHORT LINES OF beam
      LSEL,A,LINE,,6,8,2 !SELECT SHORT LINES OF beam
      LESIZE,ALL,,,plmesh !# OF ELEMENT DIVISION

      LSEL,S,LINE,,2,4,2 !SELECT LONG LINES OF beam
      LSEL,A,LINE,,5,7,2 !SELECT LONG LINES OF beam
      LESIZE,ALL,,,(plmesh*(CFL1/BeamW)) !# OF ELEMENT DIVISION


      !Piezoelectrical layer meshing thickness:
      LSEL,S,LINE,,21,24,1 !SELECT CORNER LINES OF composite LAYER 1
      LESIZE,all,,,meshthc
      LSEL,all

      !Short side of piezo:
      LSEL,S,LINE,,13,15,2 !SELECT SHORT LINES OF beam
      LESIZE,all,,,pzmesh

      !Long side of piezo:
      LSEL,S,LINE,,14,16,2 !SELECT LONG LINES OF beam
      LESIZE,ALL,,,(pzmesh*(CFL1/BeamW)) !# OF ELEMENT DIVISION

      ! Assign material to volumes
      VSEL,S,VOLU,,1 !SELECT layer 1
      VATT,1,,1 !ASSIGN ELEMENT ATTRIBUTES

      VSEL,S,VOLU,,2 !SELECT PIEZO PATCH 1
      VATT,3,,3 !ASSIGN ELEMENT ATTRIBUTES


      VSEL,ALL
      !VMESH,1,8,1
      vsweep,all

      *get,Epz,elem,,count ! Get all the number of solid elements

      !
      !
      !Bond together layers with the contact and target element !
      !
      !
      ! Define bonded contact, (from Principles of Simulating Contact Between Parts using ANSYS)
      KEYOPT,4,2,1
      KEYOPT,4,5,1
      KEYOPT,4,6,0
      KEYOPT,4,7,0
      KEYOPT,4,8,2
      KEYOPT,4,9,1
      KEYOPT,4,11,0
      KEYOPT,4,12,5 ! Keyopt 12 set to 5 is a bonded always condition


      !Target surface:
      ASEL,S,AREA,,1 ! Select area at the top and bottom of the patch
      TYPE,6 ! Selectn element type
      real,3 ! Sets the element real constant set attribute pointer
      NSLA,S,1 ! Select those nodes associated with the selected areas
      ESLN,S,0 ! Select those elements attached to the selected nodes
      ESURF,ALL ! Generate elements overlaid on the free faces of selected nodes
      ASEL,S,AREA,,8
      type,4
      real,3
      NSLA,S,1
      ESLN,S,0
      ESURF,ALL


      !Check normals:
      ESEL,S,TYPE,,4
      ESEL,A,TYPE,,6
      /PSYMB,ESYS,1
      EPLOT

      ! Reverse Contact Normal (maybe not necessary)
      ESEL,NONE
      ESEL,A,TYPE,,4
      ESURF,,REVERSE
      eplot
      ESEL,S,TYPE,,4
      ESEL,A,TYPE,,6
      eplot
      /PSYMB,ESYS,0
      ! CONTACT PAIR CREATION - END

      !
      !
      !
      !
      !
      Open-Circuit Modal Analysis
      !
      !
      !
      !
      !
      /SOLU
      antyp,modal
      nmodes = 10
      MODOPT,LANB,nmodes,0,500
      MXPAND,nmodes !Specifies the number of modes to expand and write for a modal or buckling analysis.
      !
      !
      !Load & Boundary Conditions !
      !
      !
      !Structural BCs
      nsel,s,loc,x,0
      d,all,ux,0
      d,all,uy,0
      d,all,uz,0
      alls

      solve
      finish
Viewing 1 reply thread
  • You must be logged in to reply to this topic.