266 
-4- 
The numerical results are summarised below: 
T.N.T. density 1.5 gnem? Up = 6790 milliseconds. 
in Air 
@ = 124 degrees 24 minutes p = 129 degrees 30 minutes wW = 144 degrees 
24 minutes X = 38 degrees 36 minutes. Pressure in the shock wave = 300 atms. 
In water 
= 63 degrees g = 100 degrees 36 minutes W = 127 degrees 6 minutes 
X = 52 degrees 54 minutes. Pressure in the shock wave = 56,249 atms. 
T.N.T. density 1.0 gm/em? Uni 5266 milliseconds, 
In Air 
@ = 125 degrees 6 minutes dm = 131 degrees 42 minutes W = 145 degrees 
21 minutes X = 34 degrees 48 minutes. Pressure in the shock wave = 200 atms. 
In water 
@ = S57 degrees gb = 9 degrees 6 minutes W = 125 degrees 6 minutes 
X = 50 degrees 54 minutes. Pressure in the shock wave = 31,620 atms. 
The stream lines of the flow relative to the detonation wave are shown in Figure (1) 
for air and in Figure (5) for water. The line 0D separating the explosion products from the 
surrounding air or water is shown clearly in both figures. As might be expected the expansion 
is much more rapid in air than in water. The degree of confinement obtained by surrounding 
the explosive with air and water respectively may be judged by comparing the pressure at the 
surface of separation between the products of combustion and the surrounding medium. In air 
this is only 300 atmospheres while in water it is 56,000, 
This pressure may be compared with the initial pressure at the interface between water 
and a spherical explosive, calculated by Penney as 36,000 atmospheres. In Penney's case, the 
explosion products were assumed at rest before being suddenly released. A higher figure would 
have been obtained if the motion of the gas in the detonation wave had been taken into account. 
The angles of the interface shown in Figures (1) and (5) are those which would actually 
be seen in an instantaneous photograph if the detonation process did in fact take place ina thin 
layer. 
Among other things which might be the subject of experimental test is the prediction that 
the shock wave from a bare charge of T.N.T. would travel ahead of the detonation wave if exploded 
in helium but not in air. 
TABLE I. 
T.N.T. density 1.5 
p dynes/em* @ degrees @ degrees u_cm/sec. v_cm/sec. 
15.88 x 10/0 0 90° 0 4.57 x 10° 
7.809 53° 42° 9? 2u" 3.973 x 10° 3.80 * 
a7t 68° 4B" 102° 54° 4,917 0 3.33 a 
2.299 * 81° 30° 107° 42" 5.59 ci 2.76 ¥ 
8.878 x 10° 96° 4B' 113° 6° 6.234 * 1.82 * 
4,318" 106° azo aia" 6.476" 1.28 a 
1.947 8 113° 12" 121° 18° 6.611 " 0.937" 
7,980 x 10° 119° 6° 125° 24" 6.69 * 0.736 =" 
2.880 ": 124° 24° 129° 30° 6.758 0 9.608 * 
8.707 x 107 129° 30° 133° 5u" 6.808 * 521 °* 
1,999 * 134° 4B" 138° 30° 6.852 - Cuag 0” 
2.818 x 10° 140° 4a" 1u3° 4a! 6.894 * 6360 * 
0 6.973 * 0 
Table It weeee 
