*HEADING
BENCHMARK: STRUCTURAL ACOUSTIC ANALYSIS OF AN INTERNALLY FLUID-LOADED SPHERICAL SHELL
*PART,NAME=COUPLED_MODEL
*NODE
*ELEMENT,TYPE=SAX1,ELSET=SHELL
*ELEMENT,TYPE=ASI2A,ELSET=flst
*INTERFACE,ELSET=FLST
*ELEMENT,TYPE=ACAX4,ELSET=     h2o
*NSET, NSET=  sphere
**
*shell section,elset=shell,material=steel
0.0254,
*solid section,elset=h2o,material=h2o
**
*NSET,NSET=QA_TEST
*NSET,NSET=LOADPT
*NSET, NSET=SHELL-SYM
*END PART
**
**
**
*PART,NAME=DUMMY
**************************
** THIS IS A DUMMY PART USED TO INCLUDE
** THE ANALYTIC SOLUTION OF STEPANISHEN AND COX IN
** THE OUTPUT DATABASE (.ODB) FILE. THE ANALYTIC
** SOLUTION IS FOUND IN STEPANISHEN AND COX,
** 'STRUCTURAL-ACOUSTIC ANALYSIS OF AN INTERNALLY
** FLUID-LOADED SPHERICAL SHELL: COMPARISON OF
** ANALYSTICAL AND FINITE ELEMENT MODELING RESULTS,'
** NUWC-NPT TM 00-118. THESE ANALYTIC RESULTS ARE
** FOR VELOCITY (V2) AT THE LOADPT. THE ABAQUS
** STEADY-STATE DISPLACEMENTS MUST BE MANIPULATED
** IN THE POST-PROCESSOR TO YIELD COMPARABLE DATA.
**************************
*NODE,NSET=ANALYTIC
*ELEMENT,TYPE=MASS,ELSET=ANALYTIC
*MASS,ELSET=ANALYTIC
1.0
*END PART
**
**
**
*ASSEMBLY,NAME=WHOLE
*INSTANCE,NAME=COUPLED_MODEL,PART=COUPLED_MODEL
*END INSTANCE
*INSTANCE,NAME=DUMMY,PART=DUMMY
*END INSTANCE
*END ASSEMBLY
**
**
**
*MATERIAL, NAME=steel
*elastic
2.068e11,0.3
*density
7800.
*MATERIAL, NAME=h2o
*acoustic medium,bulk modulus
*density
1000.
**
**
*amplitude,definition=tabular,name=STEPANISHEN_COX
   100.00    , 5.21706E-06,  101.00    , 5.30853E-06,  102.00    , 5.40609E-06,  103.00    , 5.51160E-06,
   104.00    , 5.62777E-06,  105.00    , 5.75886E-06,  106.00    , 5.91190E-06,  107.00    , 6.09943E-06,
   108.00    , 6.34620E-06,  109.00    , 6.70894E-06,  110.00    , 7.35281E-06,  111.00    , 9.04761E-06,
   112.00    , 4.59659E-05,  113.00    , 1.71066E-06,  114.00    , 3.92695E-06,  115.00    , 4.67124E-06,
   116.00    , 5.07451E-06,  117.00    , 5.34605E-06,  118.00    , 5.55348E-06,  119.00    , 5.72536E-06,
   120.00    , 5.87582E-06,  121.00    , 6.01276E-06,  122.00    , 6.14091E-06,  123.00    , 6.26338E-06,
   124.00    , 6.38228E-06,  125.00    , 6.49919E-06,  126.00    , 6.61531E-06,  127.00    , 6.73166E-06,
   128.00    , 6.84912E-06,  129.00    , 6.96855E-06,  130.00    , 7.09081E-06,  131.00    , 7.21684E-06,
*************************************************************
*BOUNDARY
WHOLE.COUPLED_MODEL.SHELL-SYM, 1, 1, 0.0
WHOLE.COUPLED_MODEL.SHELL-SYM, 6, 6, 0.0
*step
Frequency extraction
*frequency
50,100
*output,field
*node output
u,por
*end step
*STEP
DRIVE 100 TO 1000 HZ, 5 Hz Incs, LINEAR FREQUENCY SCALE
*STEADY STATE DYNAMICS,DIRECT,FREQUENCYSCALE=LINEAR,interval=range
100.,1000., 181, 1.0,
*CLOAD
WHOLE.COUPLED_MODEL.loadpt,2,1.0
**
*BOUNDARY,AMPLITUDE=STEPANISHEN_COX
WHOLE.DUMMY.ANALYTIC,1,1,1.0
**
*EL PRINT,FREQUENCY=99999
*NODE PRINT,FREQUENCY=999999
*OUTPUT,FIELD, FREQUENCY=177
*NODE OUTPUT
POR,U
**
*OUTPUT, HISTORY, FREQUENCY=1
*NODE OUTPUT, NSET=WHOLE.DUMMY.ANALYTIC
U,
*NODE OUTPUT, NSET=WHOLE.COUPLED_MODEL.QA_TEST
U,POR
**
*END STEP
**------------------------------------------
*STEP
*STEADY STATE DYNAMICS,FREQUENCYSCALE=LINEAR,interval=range
100.,1000., 181, 1.0,
*CLOAD
WHOLE.COUPLED_MODEL.loadpt,2,1.0
**
*EL PRINT,FREQUENCY=99999
*NODE PRINT,FREQUENCY=999999
*OUTPUT,FIELD, FREQUENCY=177
*NODE OUTPUT
POR,U
**
*OUTPUT, HISTORY, FREQUENCY=1
*NODE OUTPUT, NSET=WHOLE.DUMMY.ANALYTIC
U,
*NODE OUTPUT, NSET=WHOLE.COUPLED_MODEL.QA_TEST
U,POR
**
*END STEP