Figure 6. Gas Bubble of an Underwater Explosion. 



Frame 1 : Bubble maximum 



Frame 2: About 6msec before bubble minimum 



Frame 3: About 6msec after bubble minimum 



Frame 4: Second bubble maximum 



(times quoted refer to the condition scaled in this model test: 354 lbs TNT in 80.8 ft. depth) 



Figure 7. Shape of the bubble pulse. The record shows a later portion of the pressure-time history. 

 The Shockwave is omitted. T means the duration of the first bubble oscillation. 



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