III-43 



4.0 



20 - 



1,0 

 08 



0.6 

 0.4 I— 



ATTENUATION 

 (db/cm) Q2 







.08 



.06 



.04 - 



.02 



20 



40 



60 20 



f = FREQUENCY (kc) 



2.0 



ATTENUATION 

 (db/cm) 



J \ \ L 



20 40 



f=FREOUENCY(kc) 



60 



FIGURE III- 15 



OBSERVED ATTENUATION THROUGH BUBBLE 

 SCREENS WFTH A DISTRIBUTION OF BUBBLE 

 SIZES (AFTER MEYER AND SKUDRZYK) 



S-7001-0307 



