Добавил:
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз: Предмет: Файл:
ANSYS.pdf
Скачиваний:
875
Добавлен:
31.08.2019
Размер:
31.29 Mб
Скачать

vk.com/club152685050 | vk.com/id446425943

Rezoning Examples

elist dlist

/com check the contact definition cncheck

finish

/solution

rescontrol,,all,1

pred,off

nlgeom,on

time,1

NSUBST,10,100,5

outres,all,all solve

finish

/post1

set,1,6

prns,u,comp

prns,s,comp prns, cont finish

4.14.1.2. Rezoning Input for the Analysis

This input uses rezoning to remesh the deformed region and allow the analysis to proceed using the new mesh:

/batch,list

/clear,nostart

/filname,RznExample1

/solution

 

rezone,manual,1,6

! specify the substep to rezone

remesh,start

! start remeshing operation

esel,,,,65,128

! select region to remesh

aremesh

! create area for new mesh

lesize,10,,,8

 

lesize,31,,,10

 

lesize,18,,,6

 

amesh,2

! create the new mesh

esel,all

 

nsel,all

 

remesh,fini

! finish remeshing operation

elist

! check the new model, BC and loads

dlist

 

mapsolve,50

! map solutions

finish

 

/solution

! restart

antype,,restart

 

solve

 

finish

 

4.14.2. Example: Rezoning Using a Generic New Mesh

Following is an example simulation involving a heading assembly problem. The example uses an imported generic mesh generated by another application for the remeshing operation.

The model represents an axisymmetric hollow hemisphere that pushes down a cylindrical workpiece. The spherical ball and the grip die are modeled as rigid surfaces. Due to element distortion, the initial

Release 15.0 - © SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information

 

of ANSYS, Inc. and its subsidiaries and affiliates.

127

vk.com/club152685050Rezoning | vk.com/id446425943

run stops at t = 0.7875. Rezoning is applied at this time to achieve complete loading. The entire deformed model at substep 4 is imported into ANSYS ICEM CFD, which generates a new mesh. After reading the new mesh back in, the program creates the contact automatically when you issue the REMESH,FINISH command.

The solid element used in the model is PLANE182 (using the B-Bar method with mixed u-P formulation). CONTA171 and TARGE169 elements are also used. The material model used is a hyperelastic material with a three-parameter OGDEN option.

4.14.2.1. Initial Input for the Analysis

This is the initial mesh:

This input results in a deformed mesh and causes the analysis to terminate at t = 0.7875 seconds:

/batch, list /filname,RznExample2 /prep7

h=4.6295

b=1.5

el=b/4

xc=0

yc=2.6295

rc=2.5 PilotMove= -yc

! ogden parameters TB,HYPE,1,1,3,OGDE TBTEMP,0

TBDATA,1,3.2084E-009,7.281,0.035198,3.0149,6.3712,2.0493 et,1,182

keyopt,1,3,0

keyopt,1,6,1

et,2,169

et,3,171

keyopt,3,9,0

keyopt,3,10,1

et,4,169

et,5,171

keyopt,5,9,0

keyopt,5,10,1

mp,mu,2,0.0

r,3

r,4

k,1,xc,yc

k,2,xc,yc,yc

 

Release 15.0 - © SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information

128

of ANSYS, Inc. and its subsidiaries and affiliates.

vk.com/club152685050 | vk.com/id446425943

Rezoning Examples

k,3,rc,yc

k,4,0.0,0.0

k,5,rc+1,0.0

rect,0,b,0,h

circle,1,rc,2,3,90,1

/pnum,line,1 lplot

l,4,5 lplot aplot esize,el mat,1 type,1 real,1 amesh,1

/pnum,elem,1

/pnum,node,1

/com the 1st contact pair mat,2

real,3

type,2

esize,h

lmesh,5

lsel,,,,5 esll esurf,,reverse alls

*get,PilotID,node,,num,max

PilotID=PilotID+1

nkpt,PilotID,1 tshap, pilo e,PilotID type,3 lsel,,,,2,3 nsll,,1 esln,,0

esurf alls

/com the 2nd contact pair real,4

type,4

lmesh,6

lsel,,,,6 esll esurf,,reverse alls

type,5

lsel,,,,1,2

nsll,,1

esln,,0 esurf alls

d,PilotID,ux,0.0

d,PilotID,uy,PilotMove

d,PilotID,rotz,0.0

lsel,,,,4

nsll,,1

d,all,ux,0.0 alls lsel,,,,6 nsll,,1 d,all,uy,0.0 alls /solution pred,off

rescontrol,,all,1,

eresx,no

nlgeom,on

time,1

NSUBST,10,100,5

outres,all,all solve

Release 15.0 - © SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information

 

of ANSYS, Inc. and its subsidiaries and affiliates.

129

vk.com/club152685050Rezoning | vk.com/id446425943

finish

Following is the total elastic strain along the Y axis at t = 0.7875. The element distortion is apparent and causes the problem to diverge.

4.14.2.2. Exporting the Distorted Mesh as a CDB File

When the nonlinear analysis stops, reload the database at load step 1 and substep 4. Select all solid elements and write out to a .cdb file. (Only solid elements can be read in later when you are ready to generate the new mesh.)

/clear,nostart

 

 

 

/filname,RznExample2

 

 

/solu

! enter

solution environment

rezone,manual,1,4

! start rezoning at load step1, substep 4

eplot

! plot the elements

 

etlist

! list

the element

types

ESEL,S,TYPE,,1

!

select only

the elements of type ‘1’(solids)

cdwrite,db,RznExample2,cdb ! write out the selected elements to a CDB file finish

With the deformed mesh corresponding to load step 1, substep 4 is shown next. ANSYS ICEM CFD uses the boundary segments of this mesh next to generate the new mesh. The nodal discretization at the boundary remains same for both the old and the new mesh.

 

Release 15.0 - © SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information

130

of ANSYS, Inc. and its subsidiaries and affiliates.