Figure: Schematic of the TWERSKY problem.
The previous Pekeris problem is modified by the inclusion of surface
scatter. The rough surface involves a density of 0.092 bosses per km
of width 
and height 
. Note that the KRAKEN
\
result differs
from the KRAKENC
and SCOOTER
results. This reflects the error in
using a perturbation theory which however is probably negligible
considering the approximations of the scatter model.
'Pekeris problem with Twersky ice scatter'
10.0
1
'NSF'
0.092 8.2 5.1
500 0.0 5000.0
0.0 1500.0 /
5000.0 1500.0 /
'A' 0.0
5000.0 2000.0 0.0 2.0 0.0 0.0
1400.0 2000.0
1000.0 ! RMAX (km)
1 500.0 / ! NSD SD(1:NSD)
1 2500.0 / ! NRD RD(1:NRD)
KRAKEN- Pekeris problem with Twersky ice scatter
Frequency = 10.00 NMEDIA = 1
N2-LINEAR approximation to SSP
Attenuation units: dB/mkHz
Twersky SOFT BOSS scatter model
Twersky ice model parameters:
Bumden = 0.920000E-01 Eta = 8.20 Xi = 5.10
Z ALPHAR BETAR RHO ALPHAI BETAI
( Number of pts = 500 RMS roughness = 0.000E+00 )
0.00 1500.00 0.00 1.00 0.0000 0.0000
5000.00 1500.00 0.00 1.00 0.0000 0.0000
( RMS roughness = 0.000E+00 )
ACOUSTO-ELASTIC half-space
5000.00 2000.00 0.00 2.00 0.0000 0.0000
CLOW = 1400.0 CHIGH = 2000.0
RMAX = 1000.000000000000
Number of sources = 1
500.0000
Number of receivers = 1
2500.000
Mesh multiplier CPU seconds
1 8.08
2 6.19
I K ALPHA PHASE SPEED
1 0.4188333967E-01 -0.7143639068E-09 1500.163396
2 0.4186964892E-01 -0.2858563396E-08 1500.653927
3 0.4184681891E-01 -0.6435953313E-08 1501.472626
4 0.4181483151E-01 -0.1145206277E-07 1502.621218
5 0.4177366141E-01 -0.1791463612E-07 1504.102129
6 0.4172327607E-01 -0.2583358102E-07 1505.918494
7 0.4166363582E-01 -0.3522095285E-07 1508.074172
8 0.4159469382E-01 -0.4609093903E-07 1510.573761
9 0.4151639611E-01 -0.5845985229E-07 1513.422622
10 0.4142868154E-01 -0.7234613786E-07 1516.626905
11 0.4133148173E-01 -0.8777040005E-07 1520.193577
12 0.4122472102E-01 -0.1047554344E-06 1524.130462
13 0.4110831629E-01 -0.1233263186E-06 1528.446279
14 0.4098217683E-01 -0.1435104786E-06 1533.150699
15 0.4084620412E-01 -0.1653378169E-06 1538.254396
16 0.4070029155E-01 -0.1888408516E-06 1543.769115
17 0.4054432412E-01 -0.2140548873E-06 1549.707744
18 0.4037817804E-01 -0.2410182110E-06 1556.084403
19 0.4020172036E-01 -0.2697723168E-06 1562.914535
20 0.4001480842E-01 -0.3003621806E-06 1570.215017
21 0.3981728933E-01 -0.3328365176E-06 1578.004282
22 0.3960899938E-01 -0.3672481421E-06 1586.302458
23 0.3938976329E-01 -0.4036543176E-06 1595.131522
24 0.3915939350E-01 -0.4421171667E-06 1604.515480
25 0.3891768932E-01 -0.4827041259E-06 1614.480566
26 0.3866443598E-01 -0.5254884517E-06 1625.055467
27 0.3839940360E-01 -0.5705497741E-06 1636.271587
28 0.3812234607E-01 -0.6179747460E-06 1648.163336
29 0.3783299981E-01 -0.6678576894E-06 1660.768466
30 0.3753108238E-01 -0.7203013712E-06 1674.128458
31 0.3721629100E-01 -0.7754178193E-06 1688.288956
32 0.3688830091E-01 -0.8333291792E-06 1703.300275
33 0.3654676364E-01 -0.8941686039E-06 1719.217978
34 0.3619130513E-01 -0.9580810818E-06 1736.103543
35 0.3582152384E-01 -0.1025224135E-05 1754.025132
36 0.3543698884E-01 -0.1095768032E-05 1773.058466
37 0.3503723827E-01 -0.1169895081E-05 1793.287833
38 0.3462177842E-01 -0.1247796785E-05 1814.807209
39 0.3419008460E-01 -0.1329666243E-05 1837.721486
40 0.3374160587E-01 -0.1415679057E-05 1862.147680
41 0.3327577965E-01 -0.1505943298E-05 1888.215805
42 0.3279207350E-01 -0.1600349816E-05 1916.068317
43 0.3229012280E-01 -0.1697989094E-05 1945.853643
44 0.3177042607E-01 -0.1793021126E-05 1977.683678
Figure: Transmission loss for the TWERSKY problem.