*HEADING
VERIFICATION OF AC2D4 BY CAVITY FREQUENCY CALCULATION - HALF MODEL  
*NODE
  1,0
  5,0    ,0.1120
 41,0.113,0
 45,0.113,0.1120
 61,0.123,0
 65,0.123,0.1120
101,0.236,0.
105,0.236,0.1120
*NGEN,NSET=BOTTOM
  1, 41,10
 41, 61,10
 61,101,10
*NGEN,NSET=TOP
  5, 45,10
 45, 65,10
 65,105,10
*NFILL
BOTTOM,TOP,4
*NSET,NSET=ASYM
53,54,55
*ELEMENT,TYPE=AC2D4
 1,  1, 11, 12,  2
*ELGEN,ELSET=ALL
  1,3,1,1,4,10,10
** 31,2,30,30
** 61,2,1,1,4,10,10
  3,2,1,1,5,10,10
*MATERIAL,NAME=ALL
*DENSITY
 1.,
*ACOUSTIC MEDIUM,BULK MODULUS
1.183E5, 
*SOLID SECTION,MATERIAL=ALL,ELSET=ALL
 1,
*STEP
*FREQUENCY, eigensolver=lanczos, SIM=NO
 10, , ,-10.
*MODAL FILE
*END STEP
*STEP
*FREQUENCY, eigensolver=lanczos, SIM=NO
 10, , ,-10.
*BOUNDARY
ASYM,8,8
*MODAL FILE
*END STEP