Environmental Engineering Reference
In-Depth Information
But for certain purpose, only one or several kinds of explosion are effective. The
total work capacity of liquid explosives is expressed in Eq.
2.32
.
A ¼ A
1
þ
A
2
þ
A
3
...þ
A
n
ð
2
:
32
Þ
Here, A
1
,A
2
, A
3
,...A
n
is the work of each explosive effect. A
T
is the sum of all
work.
The sum of all explosion effect of liquid explosives for the surrounding media is
the work of explosives, or the work capacity of explosives. The capacity is also the
power of explosives. It can be calculated from theory or obtained from experiments.
2.3.1.1 Ways to Express the Work Capacity of Liquid Explosives
If the work of liquid explosives to the surrounding is done through the adiabatic
expansion of high-temperature and high-pressure gas products, according to the
rst
law of thermodynamics, the decrease in the internal energy of a system is equal to
the total released heat and work done to the surroundings.
du ¼
dQ
þ
dA
ð
2
:
33
Þ
du is the decrease in the internal energy of explosive system; dQ is the
heat released to the surroundings from the explosive system; dA is the work done to
the surroundings.
According to the adiabatic assumption of expansion, dQ = 0. So Eq.
2.33
is
changed to
Here,
-
du ¼
C
v
dT
dA ¼
After integration of A, Eq.
2.34
is obtained.
Z
Z
T
2
T
1
CvdT ¼
T
2
C
v
dT ¼ C
v
T
1
T
2
A ¼
ð
Þ
ð
2
:
34
Þ
T
2
Here, T
1
is the explosion temperature; T
2
is the
final temperature after cooling
C is usually used as the standard temperature); C
v
is the average constant
volume heat capacity of explosive products between T
1
and T
2
.
The explosion heat has below relationship.
down (15
°
Qv ¼ Cv T
1
T
2
ð
Þ
ð
2
:
35
Þ
Here, E is the mechanical equivalent of heat; Q
v
is the explosion heat of an
explosive; A = EQ
v
is the potential energy of an explosive, which is the total work
