*Heading
 AXISYMMETRIC TIRE-AIR INTERACTION
*preprint,model=yes,HIST=yes
*Node,NSET=AIR
*Element, type=ACAX4,ELSET=AIR
*Solid Section, elset=air, material=air
1.,
*Node,nset=tire
*Element, type=CAX4H,elset=tire
*Solid Section, elset=tire, material=rubber
1.,
*NSET,NSET=longlongnout
*nset,nset=cload
*NSET,NSET=nout
*Nset, nset=SYMS
*Nset, nset=CENT
*NSET,NSET=SYMA
*Elset, elset=air_S2
*Elset, elset=air_S1, generate
*Surface, type=ELEMENT, name=air
 air_S2, S2
 air_S1, S1
*Elset, elset=liner_S4, generate
*Elset, elset=liner_S2, generate
*Surface, type=ELEMENT, name=liner
 liner_S4, S4
 liner_S2, S2
** Constraint: air-liner
*Tie, name=air_liner, adjust=no
 air, liner
**
*Material, name=air
*Acoustic Medium
*Density
 1.2e-3,
*Material, name=rubber
*Hyperelastic
 100., 0.
*Density
 1.1e-3,
*Surface Interaction, name=air_liner
1.,
**
** ----------------------------------------------------------------
**
*nset,nset=retained,unsorted
*STEP,nlgeom
*STATIC
*END STEP
*STEP
*FREQUENCY,norm=mass
65,,,-1
*BOUNDARY,op=new
retained,1,2
*OUTPUT,FIELD
*NODE OUTPUT
U,
*END STEP
** ----------------------------------------------------------------
*step
*substructure generate,type=z1,overwrite,libr=smalltire_acax4,
recovery matrix=yes, mass matrix=yes
*boundary,op=new
*retained nodal dofs,sorted=no
retained,
*retained eigenmodes,generate
*substructure load case,name=loadcase1
*cload
cload,1,0.1
*substructure matrix output, stiffness=yes,file=smalltire_acax4,
mass=yes, recovery=yes,sload=yes
*end step
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