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ANSYS: melting using element death--how to transfer convection BC from deactivated elements?
I am modelling melting by element death. I have a cold (melting) rectangle with a hot fluid convecting at the exterior. I am using a do loop so that time increases at each loop. I define a "melting" temperature, so that elements are killed off when they achieve a specified temperature.
The problem I'm having is that I'm getting this error: "Surface loads on line x are not transferred to unselected element y". I think this means that the convection boundary conditions are not being transferred from the exterior, deactivated/killed elements to the active (not yet melted) ones. Does anyone know how to deal with this?
Here is my code...I'm a pretty new user, so any other comments about improving code are welcome! Thanks a lot:
finish
/clear
/title, Convection melting example
/prep7 ! Enter the preprocessor
! define geometry
k,1,0,0 ! Define keypoints
k,2,0.03,0
k,3,0.03,0.03
k,4,0,0.03
a,1,2,3,4 ! Connect the keypoints to form area
! Mesh 2D areas
ET,1,Plane55 ! Element type
MP,Dens,1,2262e9 ! Define density
mp,c,1,0.001604 ! Define specific heat
mp,kxx,1,1.8 ! Define heat transfer coefficient
type,1
mat,1
esize,0.0014 ! Mesh size
amesh,all ! Mesh area
! Boundary conditions
/PSF,CONV, ,2,0
! Convection
FLST,2,1,4,ORDE,1
FITEM,2,4
SFL,ALL,CONV,100, ,1200,
finish
/SOLU
ANTYPE,trans
TRNOPT,FULL
NROPT,AUTO, ,
EQSLV,
SOLCONTROL,ON
AUTOTS,on
!lumpm,0 ! Lumped mass off
!nsubst,10 ! Number of substeps, 20
!neqit,10 ! Max no. of iterations
lnsrch,on ! Line search on
OUTRES,ALL,ALL,
KBC,1 ! step
! load step 1, initial conditions 25 C
330 C
TIME,0.001
DELTIM,0.001,0.001,0.001,
TUNIF,330,
solve
! load step 2..... , apply moving heat conv
j=0.1
*DO,j,1,900,100
/solu
TIME, j
DELTIM,1,1,1,
SFDELE,ALL,CONV
NSEL,INVE ! Selects all inactive nodes (those not attached to any active elements)
D,ALL,ALL,0 ! Constrains all inactive DOFs (optional)
nsel,s,ext ! Node select all exterior nodes
sf,all,CONV,100,1200
kbc,1
NSEL,ALL ! Reselect all nodes
/gst,off
solve
finish
/post1
set, last
etable,melty,temp, ! Create an element table
esel,s,etab,melty,350 ! select all elements from table above 500
finish
/solu ! Re-enter solution phase
nropt,full
antype,,rest ! Restart analysis
ekill,all ! Kill all selected elements
esel,s,live
finish
j=j+1
/post1
/NOPR
set,last
esel,s,live ! Select all live elements
plnsol,temp ! Plot the temp contour of the live elements
/CONTOUR,1,20,200,50,1200
/WAIT, 2
*ENDDO
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Comments
how to transfer convection BC from deactivated elements?
sir..,
I am a Post Graduate student of thermal engineering specialisation & i tried several times on this code...,in ANSYS APDL. but, i did not get the melting process., it seems that there might be a mistake in this., can you please give me the correct APDL Code.,