*HEADING
 TIRE AIR COUPLED ACOUSTIC MODEL WITH TRANSPORT EFFECTS
 3D FULL TIRE MODEL
 STEP 0: TRANSFER BASE STATE FROM sst_acoustic_rev
 STEP 1: ESTABLISH EQUILIBRIUM
 STEP 2: CHANGE FRICTION
 STEP 3: FREQUENCY EXTRACTION AT ZERO ROLLING SPEED
 STEP 4: STEADY STATE DYNAMICS DIRECT WITH VERTICAL ROAD
 EXCITATION
 STEP 6: COMPLEX EIGENANALYSIS
 UNITS: KG, M
*RESTART,WRITE,OVERLAY
*SYMMETRIC MODEL GENERATION,REFLECT=LINE,
ELEMENT=100000,NODE=100000
*SYMMETRIC RESULTS TRANSFER
*NSET,NSET=AIRCROWN
*NSET,NSET=AIRFOOT
*NSET,NSET=AIRSIDE
*NSET,NSET=SIDE
********************************************
*STEP,INC=100,NLGEOM=YES
 1:  FOOTPRINT (LOAD CONTROLLED)
*STATIC
 1.0, 1.0
*BOUNDARY,OP=NEW
 TIRE-RIM,  1, 6
 ROAD, 1, 2
 ROAD, 4, 6
*DSLOAD,OP=NEW
 TIRE-LINER, P, 200.E3
*CLOAD, OP=NEW
 ROAD, 3, 3300.
*OUTPUT,FIELD,FREQ=10
*NODE OUTPUT
 U,
*NODE OUTPUT,NSET=AIR
 POR,
*ELEMENT OUTPUT,VAR=PRE
*OUTPUT,HISTORY,FREQ=1,VAR=PRE
*END STEP
********************************************
*STEP,INC=100,NLGEOM=YES
 2:  CHANGE FRICTION
*STATIC
 1.0, 1.0
*CHANGE FRICTION,INTERACTION=SRIGID
*FRICTION
 0.1,
*BOUNDARY,OP=NEW
 TIRE-RIM,  1, 6
 ROAD, 2, 2
 ROAD, 4, 6
*END STEP
*******************************
*STEP,NLGEOM
 3: EXTRACT EIGENVALUES
*FREQUENCY,EIGENSOLVER=LANCZOS
 12, 200.0,260.0
** 92, 20.0, 260.0 -> to produce manual figures
*OUTPUT,FIELD,FREQ=1
*NODE OUTPUT
 U,
*NODE OUTPUT,NSET=AIR
 POR,
*END STEP
*******************************
*STEP,INC=50,NLGEOM
 4: RESPONSE TO VERTICAL EXCITATION (DIRECT)
*STEADY STATE DYNAMICS, DIRECT,INTER=EIGEN
 225.0, 235.0, 3
** 200.0, 260.0, 7 -> to produce manual figures
*BOUNDARY
TIRE-RIM,1,6
ROAD,1,2
ROAD,4,6
**
*BOUNDARY
 ROAD,3,3,0.001
**
*OUTPUT,HISTORY,FREQ=1
*NODE OUTPUT,NSET=AIRCROWN
POR,
*NODE OUTPUT,NSET=AIRFOOT
POR,
*NODE OUTPUT,NSET=AIRSIDE
POR,
*NODE OUTPUT,NSET=SIDE
U,
*NODE OUTPUT,NSET=ROAD
U,RF
*END STEP
*******************************
*STEP,NLGEOM
 6: COMPLEX EIGENVALUES
*COMPLEXFREQUENCY
*ENDSTEP