Ill -52 



2000 — 



PHASE VELOCITY 

 (m/sec) 



1 

 1 



I 

 1 



/ 



\ 

 \ . 



\ • 





1 







^ 





1 ••' 



"^^- • : ...... .. 





'. 



• 



-^ •*• .* .";/ 







1 1 1 



1 



1 1 1 1 1 1 1 1 1 



30 60 90 120 150 180 210 240 270 300 330 360 390 420 

 f- FREQUENCY (kc) 



Q. PLOT OF PHASE VELOCITY vs FREQUENCY SHOWING ALL OF THE RELIABLE 

 DATA OBTAINED. 



ATTENUATION 

 (db/cm) 





r. 





/\ 



- 



4 



- 







'11' ''^\ ' 





ll ' ^ • \" 





w' '• ^ A ' 





- / ■ ^ -X 



— 



• / \ . \ 





••/• ..\ •' \^ 



— 



'/•' • \ " ' N. 





'/• ''^•' ^V 



,'i 



r- "NJ , >v 



d 



1 1 1 1 1 1 1 1 1 r 1 



30 60 90 120 150 180 210 240 270 300 330 360 390 

 f^FREQUENCY (kc) 



b. PLOT OF ABSORPTION vs FREQUENCY SHOWING ALL OF THE RELIABLE 

 DATA OBTAINED. 



FIGURE III-23 PHASE VELOCITY AND ATTENUATION THROUGH A 



SCREEN HAVING THE BUBBLE DISTRIBUTION OF 

 FIGURE m-22 (AFTER FOX, CURLEY AND LARSON) 



S-7001-0307 



