*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 0.0, 0.0, 0.0, 0.0, 0.0, 1.0 *SYMMETRIC RESULTS TRANSFER *NSET,NSET=AIRCROWN 211 *NSET,NSET=AIRSIDE 15211 ******************************************** *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 1.0, *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 reproduce the figures in the manual *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, FREQUENCY SCALE=LINEAR, INTERVAL=RANGE 225.0, 235.0, 10 ** 200.0, 260.0, 121 ---> To reproduce the figures in the manual *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=AIRSIDE POR, *NODE OUTPUT,NSET=ROAD U,RF *END STEP *******************************