/BATCH,LIST
/VERIFY,EV129-1S
/PREP7
/TITLE,AMA,EV129-1S,FLUID129,HARMONIC ANALYSIS
ET,1,PLANE42 ! structural element
ET,2,FLUID29 ! acoustic fluid element with ux & uy
et,3,129 ! acoustic infinite line element
r,3,0.5207,0,0
ET,4,FLUID29,,1,0 ! acoustic fluid element without ux & uy
! material properties
MP,EX,1,2.068e11
MP,DENS,1,7929
MP,NUXY,1,0
MP,DENS,2,1030
MP,SONC,2,1460
! create inner and outer quarter circles
CYL4,0,0,0.254,0,0.26035,90
CYL4,0,0,0.26035,0,0.5207,90
! select, assign attribute to and mesh area 1
ASEL,S,AREA,,1
AATT,1,1,1,0
LESIZE,1,,,16,1
LESIZE,3,,,16,1
LESIZE,2,,,1,1
LESIZE,4,,,1,1
MSHKEY,1
MSHAPE,0,2D ! mapped quad mesh
AMESH,1
! select, assign attribute to and mesh area 2
ASEL,S,AREA,,2
AATT,2,1,2,0
LESIZE,5,,,16,1
LESIZE,7,,,16,1
LESIZE,6,,,5
LESIZE,8,,,5
MSHKEY,0
MSHAPE,0,2D ! mapped quad mesh
AMESH,2
! reflect quarter circle into semicircle about x-axis
nsym,x,1000,all ! offset node number by 1000
esym,,1000,all
! reflect semicircle into full circle about y-axis
nsym,y,2000,all ! offset node number by 2000
esym,,2000,all
NUMMRG,ALL ! merge all quantities
! modify outer 2 layers of el29 into type 4
esel,s,type,,1
nsle,s
esln,s,0
nsle,s
esel,inve
nsle,s
emodif,all,type,4
esel,all
nsel,all
! define el129 line element
csys,1
nsel,s,loc,x,0.5207
type,3
real,3
mat,2
esurf
esel,all
nsel,all
! flag interface as fluid-structure interface
nsel,s,loc,x,0.26035
esel,s,type,,2
sf,all,fsi,1
nsel,all
esel,all
FINISH
! enter solution module
/SOLU
ANTYPE,harmic ! select harmonic analysis
hropt,full
f,19,fx,1000.
f,1019,fx,-1000.
harfrq,34.,38.
nsubst,100
kbc,1
SOLVE
FINISH
! postprocess
/post26
plcplx,0
nsol,2,1,u,x,d1ux
store
conjug,3,2
prod,4,2,3
sqrt,5,4
*get,uxmx,vari,5,extrem,tmax
/COM -------------------------------------------------------------
/COM Expected Result:
/COM
/COM The following "uxmx" should equal 35.24 Hz.
/COM -------------------------------------------------------------
*status,uxmx
finish |