Ill -37 



REFLECTION 



COEFFICIENT 



(db) 



FIGURE in-25 



20 30 40 50 60 



f ^FREQUENCY (kc/s) 



REFLECTION OF NORMALLY INCIDENT SOUND FROM 

 A SINGLE LATTICE SCREEN (AFTER MacPHERSON) 



VELOCITY 

 (fps) 





[d 2 in. diameter pipe 





EXPERIMENT ] O 3IN. DIAMETER PIPE 

 **'^>^>»^ [ a CAMPBELL & PITCHER(8) 



1,000 



^^^*-^^ f SPITZER 





^afc^^ THEORY |__^^^^ 





""^><L ^ 



100 



^^lA 





Sft^/w 





NOTE: DATA AND CURVES 





ARE REDUCED TO 



in 



15.8psi.abS., AND 80°F 



lO-'* 10-3 10-2 10-1 1 



CONCENTRATION (Proportion of Air to Mixture by Volume) 



FIGURE III-26 PHASE VELOCITY IN AIR- WATER MIXTURES (AFTER 



SILBERMAN) 



S-7001-0307 



