





B 





8 













a 































9 





















a 



^ 



0^-^" 









a a 













« « 



























e 



i ° 

























e 















Period 



e Sing 



• 5.3 MC 



tngth ■ 101. ft 



a manifold 





• 







• 









































































Pet Attenuation 

 a. Wave Period = 5.3 s 













1 | 



1 





— — J- — fTaZ-J- — i 



















l_ 



^5-— - 



G 





J^A 



| 









B 



s 







k 













k^ 















^ " 



" 









$ 











^\ 









^ 



































^\ 





s 

















4 

 r 



V 









1 



























J* 





























/ 







































/ 









































/ 







/ 



V* 











© 



e 







' 













I 



/ 





/ 



/ 

















wovalmjth ■ 6 



.6 ft 











/ 





/ 











\ 







B OouDIo morvifold 

 A Tripli monlfold 











I 



/ 





































V 







































Pet Attenuation 

 b. Wave Period = 3.75 s 



Figure 149.. Air discharge versus wave height attenuation in large-scale 

 pneumatic breakwater system tests (after Sherk, 1960). 



210 



