1088 
energy than would be obtained by integrating to some fixed time which 
is independent of weight and distance. 
Log rfivl/S (reduced impulse) is plotted against log wl/3/R in 
Fige 4, and the empirical equations obtained from the best straight 
line through the experimental points and the standard deviation of the 
experimental points from the line is; 
I = 1.46 wi/3 (W2/3 /R)0+89 mo 10.3% 
The experimental ourves are not concave downward as is the theoreti- 
cal curve, which is shown,as a dotted line on Fig. 4. The spherical 
pentolite impulse ourve®/ agreed with the theoretical curve in this re- 
spect, but the linearity ,of the TNT ,impulse curve is to be expeoted since 
the log time oonstant/W oe log wl/3/R relation is nearly linear. 
(d) Energy:--The energy factor (E) reported here is defined as: 
1 -6 
075 
(where @ is the nominal time constant at the parfyoular value of w/3 7p) 
and contains the correction for finite amplitude yhough the "afterflow" 
terms are omitted. Figure 5 is a plot of log E/\l versus log wi/5/ 
for TNT. The empirical equation for energy as a function of oharge 
weight and charge-to-gauge distance obtained from the best straight line 
through the experimental points is: 
From Fige 5, for TNT, 
B= 2.44 x 10° wi/S (wi/S py? +O 
with the standard deviation of the experimentally determined values from 
the line of 16.0%. 
The total energy flux density per unit area is given by the equations 
1 
fo 
where F 
Fe 
(s'265%x 207° p..). f 827? pat + sof Bee pueda as] 
° @ ° 
total energy flux 
p = pressure as a function of time in 1b/in.* 
P, = peak pressure in 1b/in.? 
t = time in seconds 
o. = velocity of sound in sea water at given 
temperature in ft/seo 
