*HEADING
EXPLICIT TO STANDARD IMPORT OF ACOUSTIC ELEMENTS 
*RESTART, WRITE
*PARAMETER
f=15
T1=0.005
omega=2*3.14159*f
*NODE, NSET=BACK_S
 1,  0.0, 0.0, 1.0
 3,  0.0, 0.0, 0.0
 7,  0.0, 1.0, 0.0
 5,  0.0, 1.0, 1.0
1010,0.0, 0.0, 0.5
1100,0.0, 1.0, 0.5
*NODE, NSET=FRONT_S
 2, 2.0, 0.0, 1.0
 4, 2.0, 0.0, 0.0
 8, 2.0, 1.0, 0.0
 6, 2.0, 1.0, 1.0
1030,2.0, 0.0, 0.5
1300,2.0, 1.0, 0.5
*NODE, NSET = CENTER_S
 101, 1.0, 0.0, 1.0
 102, 1.0, 0.0, 0.0
 103, 1.0, 1.0, 0.0
 104, 1.0, 1.0, 1.0
1020,1.0, 0.0, 0.5
1200,1.0, 1.0, 0.5
*NODE, NSET=BACK_F
 22, 2.0, 0.0, 1.0
 24, 2.0, 0.0, 0.0
 26, 2.0, 1.0, 1.0
 28, 2.0, 1.0, 0.0
1040,2.0, 0.0, 0.5
1400,2.0, 1.0, 0.5
*NODE, NSET=FRONT_F
 12, 3, 0.0, 1.0
 14, 3, 0.0, 0.0
 16, 3, 1.0, 1.0
 18, 3, 1.0, 0.0
1050,3.0, 0.0, 0.5
1500,3.0, 1.0, 0.5
*NODE
60, 4.0, 0.0, 1.0
61, 4.0, 0.0, 0.5
62, 4.0, 0.0, 0.0
63, 4.0, 1.0, 1.0
64, 4.0, 1.0, 0.5
65, 4.0, 1.0, 0.0
*NSET, NSET=NODE2
FRONT_S,
*NSET, NSET=SOLID
FRONT_S,CENTER_S,BACK_S
*NSET, NSET=QA_TEST
26,1400,28,24,1040,22
*NSET,NSET=ACOUS
BACK_F,FRONT_F
*ELEMENT, TYPE=C3D8R, ELSET=SOLID
1,1,1010,1100,5,101,1020,1200,104
2,1010,3,7,1100,1020,102,103,1200
3,101,1020,1200,104,2,1030,1300,6
4,1020,102,103,1200,1030,4,8,1300
*ELEMENT,TYPE=AC3D6, ELSET=FLUID
5,1400,26,22,1500,16,12 
6,22,1040,1400,12,1050,1500
7,1400,1040,24,1500,1050,14
8,24,28,1400,14,18,1500
9,1500, 16, 12,64,63,60
10,12,1050,1500,60,61,64
11,18,1500,1050,65,64,61
12,1050,14,18,61,62,65
*ELEMENT, TYPE=ACIN3D3, ELSET=INF
13, 64,63,60
14, 60,61,64
15, 65,64,61
16, 61,62,65
*ELSET,ELSET=QA_TEST
3,4
*SOLID SECTION, ELSET=SOLID, MATERIAL=ELAS
*MATERIAL, NAME=ELAS
*ELASTIC
207E9,0.3
*DENSITY
7800.0
*SOLID SECTION,ELSET=INF, MATERIAL=FLUID
1.0, -100.0, 0.5, 0.5
*****
*SOLID SECTION, ELSET=FLUID, MATERIAL=FLUID
*MATERIAL, NAME=FLUID
*ACOUSTIC MEDIUM
2.25E9
*DENSITY
1000.0
**
*SURFACE,NAME=SOLID
3,S2
4,S2
*SURFACE,NAME=FLUID
5,S1
6,S1
7,S1
8,S1
*TIE,NAME=COUPLE
SOLID,FLUID
**
*BOUNDARY
BACK_S,1,3
**
*AMPLITUDE,NAME=SINE,DEF=PERIODIC
1,<omega>,0.0,0.0
0,1,0,0
**
** Step 1
**
*STEP
*DYNAMIC,EXPLICIT
,<T1>
*BOUNDARY, AMP=SINE
FRONT_F,8,,1.e3
*OUTPUT, FIELD, NUMBER INTERVAL=20, VARIABLE=PRESELECT
*OUTPUT, HISTORY, TIME INTERVAL=25.E-6, VARIABLE=PRESELECT
*OUTPUT, FIELD, NUMBER INTERVAL=2
*NODE OUTPUT, NSET=QA_TEST
POR
*END STEP