292 Lecture 15 
coefficient 
Varying hourglass’ modes 
damping 
Acoustic 
+0 
Long wavelengthy/ Radiated wavelength 
(o< Frequency ) 
Fig. 15.15. Junger's "cutoff" frequency. 
150 
~ 
5 
100 
ov 
i= 
= 
uv 
N 
° 
fe) 
©) 
z 
we} 
mo) 
o 
= 50 
ie 300 fr 
S L000 ft Distance from submarine 
fe) at go° to path at nearest 
10.000ftJ point. 
§ 
E 
6 
= 
0 
50 100 
Velocity ft/sec 
Fig. 15.16. Radiated sound from smooth rigid submarine (surface area, 18,000 ft”), 
