*HEADING
 ECA4AFAD: ACAX4 ELEMENTS
 Acoustic test - 1D Problem, SS-DIRECT.
 A 4m long tube; from left to right,
 a sound source, 3m is air, then 1m of a highly
 absorbent material, followed by a rigid
 termination. 
*PREPRINT,ECHO=NO,HISTORY=NO,MODEL=YES
*RESTART,WRITE
***********************************************************
**
**
**   Mesh Generation
**
*NODE, Nset=ODB_NSET
    1,0,
  401,4,
 1001,0, 2E-2
 1401,4, 2E-2
*NGEN,NSET=ALL
   1,401
 1001,1401
*NSET,NSET=QA_TEST,GENERATE
 1,401,10
*NSET,NSET=LOAD
 1,1001
*ELEMENT,TYPE=ACAX4
 1,1,2,1002,1001
*ELGEN,ELSET=CHANNEL
 1,300
*ELEMENT,TYPE=ACAX4
  301,301,302,1302,1301
*ELGEN,ELSET=ABSORB
  301,100
**
**
************************************************
**    ** ELEMENT PROPERTIES **
**
*SOLID SECTION,MATERIAL=AIR,ELSET=CHANNEL
*SOLID SECTION,MATERIAL=ABSORB,ELSET=ABSORB
**
**
*MATERIAL,NAME=AIR
*DENSITY
 1.21,
*ACOUSTIC MEDIUM,BULK MODULUS
 0.1424E6,
**
**
*MATERIAL,NAME=ABSORB
*DENSITY
 1.21,
*ACOUSTIC MEDIUM,BULK MODULUS
 0.1424E6,
*ACOUSTIC MEDIUM,VOLUMETRIC DRAG
 1e4,
**
**
**
*************************************************
**
** Sets added by addodb
**
*Elset,Elset=ODB_ESET
CHANNEL, ABSORB
**
**
*Nset, Nset=ODB_NSET
ODB_NSET, ALL, QA_TEST, LOAD
**
**
*STEP
*STEADY STATE DYNAMICS,DIRECT,FREQUENCY SCALE=LINEAR
 10,1100,13,1
**
** Prescribe outward acceleration of 100 at loaded nodes.
** The tributary area of each node is 1/100, so the
** outward volume acceleration is 1.
**
*CLOAD
 LOAD,8, -1
*NODE PRINT, NSET=QA_TEST
 POR,PPOR,
*EL PRINT,FREQUENCY=0
*OUTPUT,FIELD, OP=NEW
*NODE OUTPUT,NSET=QA_TEST
 POR,
*ELEMENT OUTPUT,ELSET=ABSORB
ACV,INTEN,GRADP
*OUTPUT,HISTORY
*NODE OUTPUT,NSET=QA_TEST
 POR,
*ENDSTEP