*HEADING
EC34AFAW: Nonreflective end, complex material via volumetric
drag and direct 
Compare IMPEDANCE WITH SIMPEDANCE, and STEADY STATE DYNAMICS, DIRECT
with SUBSPACE PROJECTION.
********************
*part,name=duct1
*NODE, Nset=ODB_NSET
1,    0, 0
41,  .5, 0
51,   0, 1.e-2
91,  .5, 1.e-2
101,  0, 2.e-2
141, .5, 2.e-2
201,  0, 1.e-2,1.e-2
241, .5, 1.e-2,1.e-2
501,  0,  0, 1.e-2
541, .5,  0, 1.e-2
601,  0, 2.e-2, 1.e-2
641, .5, 2.e-2, 1.e-2
1001, 0,  0, 2.e-2
1041,.5,  0, 2.e-2
1051, 0, 1.e-2, 2.e-2
1091,.5, 1.e-2, 2.e-2
1101, 0, 2.e-2, 2.e-2
1141,.5, 2.e-2, 2.e-2
*NGEN,NSET=NALL
1,41
101,141
1001,1041
1101,1141
*NSET,NSET=LOAD
1,101, 1001,1101
*NSET,NSET=QA_TEST,GENERATE
1,41
*ELEMENT,TYPE=AC3D4,ELSET=EALL
    1,    1,    3,  103, 1001
    2,    3,  103, 1001, 1003
    3,  103, 1001, 1003, 1103
    4,    1,  103,  101, 1001
    5,  103,  101, 1001, 1103
    6,  101, 1001, 1103, 1101
*ELGEN,ELSET=EALL
1,20,2,6
2,20,2,6
3,20,2,6
4,20,2,6
5,20,2,6
6,20,2,6
*SOLID SECTION,MATERIAL=ABSORB,ELSET=EALL
1.,
*end part
**
*part,name=duct2
*NODE, Nset=ODB_NSET
1,    0, 0
41,  .5, 0
51,   0, 1.e-2
91,  .5, 1.e-2
101,  0, 2.e-2
141, .5, 2.e-2
201,  0, 1.e-2,1.e-2
241, .5, 1.e-2,1.e-2
501,  0,  0, 1.e-2
541, .5,  0, 1.e-2
601,  0, 2.e-2, 1.e-2
641, .5, 2.e-2, 1.e-2
1001, 0,  0, 2.e-2
1041,.5,  0, 2.e-2
1051, 0, 1.e-2, 2.e-2
1091,.5, 1.e-2, 2.e-2
1101, 0, 2.e-2, 2.e-2
1141,.5, 2.e-2, 2.e-2
*NGEN,NSET=NALL
1,41
101,141
1001,1041
1101,1141
*NSET,NSET=LOAD
1,101, 1001,1101
*NSET,NSET=QA_TEST,GENERATE
1,41
*ELEMENT,TYPE=AC3D4,ELSET=EALL
    1,    1,    3,  103, 1001
    2,    3,  103, 1001, 1003
    3,  103, 1001, 1003, 1103
    4,    1,  103,  101, 1001
    5,  103,  101, 1001, 1103
    6,  101, 1001, 1103, 1101
*ELGEN,ELSET=EALL
1,20,2,6
2,20,2,6
3,20,2,6
4,20,2,6
5,20,2,6
6,20,2,6
*SOLID SECTION,MATERIAL=ABSORB,ELSET=EALL
1.,
*end part
**
*assembly,name=AcousticMaterialTest
*instance,part=duct1,name=duct1
*end instance
*instance,part=duct2,name=duct2
0,0.1,0
*end instance
*Elset,Elset=ODB_ESET
DUCT1.EALL,DUCT2.EALL
*Nset, Nset=QA_TEST
DUCT1.qa_test,DUCT2.QA_TEST
*NSET,NSET=LOAD
DUCT1.LOAD,DUCT2.LOAD
*surface,NAME=NRS
DUCT1.116,S2
DUCT2.116,S2
DUCT1.117,S4
DUCT2.117,S4
*Nset,Nset=corners
duct1.101,duct1.1,duct2.101,duct2.1
*nset,nset=mid
duct1.51,duct2.51
*end assembly
**
*MATERIAL,NAME=ABSORB
*DENSITY
 1.21,
*ACOUSTIC MEDIUM,BULK MODULUS
 0.1424E6,
*ACOUSTIC MEDIUM,VOLUMETRIC DRAG
1400.,
**
*MATERIAL,NAME=complex
*ACOUSTIC MEDIUM,COMPLEX DENSITY
 1.21, -2.2282,100.0
*ACOUSTIC MEDIUM,BULK MODULUS
 0.1424E6,
**
*AMPLITUDE,NAME=OMEGA
0.,0., 1E6,6.2831853E6
************************************************
**       ** ANALYTIC SOLUTION  **
**  
**  at freq=100,
**  Impedance: Z = root( K_f (rho  - i r/omega))
**               = 516.411 -307.208 i
**  Propagation constant 
**             b = i (omega/K_f) Z
**               = 1.35551 + 2.27859 i
**
**  Solution: with nonreflective end,
**  Complex pressure
**             p(x) = Z v(0) exp( - b x)
**  i.e. |p(x)| = |Z v(0)| exp ( - Re(b) x)
**              = 600.8805  exp ( -1.35551 x)
**
**       Arg(p) = Arg(Z) - Im(b) x
**       ppor   = -30.74799 - 130.5534 x
**
************************************************  
*physi,spl=1.23456
**
**
**
*STEP
*FREQUENCY,NORM=MASS,EIGENSOLVER=LANCZOS,SIM,Ac=off
50, , ,
*NODE PRINT,F=0
*EL PRINT,F=0
*OUTPUT,FIELD,Frequency=0
*END STEP
**
**
*STEP
*STEADY STATE DYNAMIC,SUBSPACE PROJECTION
100,1000,20
***IMPEDANCE
** duct1.116,I2
** duct1.117,I4
** duct2.116,I2
** duct2.117,I4
**
*CLOAD,LOAD CASE=2, AMP=OMEGA
LOAD, 8, 1.e-4
*ENERGYPRINT
*OUTPUT,FIELD
*NODE OUTPUT
POR,SPL
*END STEP
**
*STEP
*STEADY STATE DYNAMIC,SUBSPACE PROJECTION
100,
***SIMPEDANCE
**NRS, 
*CLOAD,LOAD CASE=2, AMP=OMEGA
LOAD, 8, 1.e-4
*ENERGYPRINT
*OUTPUT,FIELD
*NODE OUTPUT
POR,SPL
*OUTPUT,HISTORY
*NODE OUTPUT,NSET=QA_TEST
POR,
*END STEP