Environmental Engineering Reference
In-Depth Information
The crosspoints of these two lines are S and W. But in normal detonation, Rayleigh
line is tangential to Hugoniot curve (the detonation adiabatic curve). And the
contact point is P. Figure
2.6
gives the relative positions of Rayleigh line and
Hugoniot curve.
The contact point P corresponds to normal detonation or CJ detonation. The high
crosspoint S correlates super pressure detonation. The low crosspoint W corre-
sponds to under-compressed detonation.
N and N
, which are the crosspoints of two Rayleigh lines and shock/impact
adiabatic curve, correlate with the shock/impact compression condition of
initiations.
Point W, which is different from S, is in the weak branch under the contact point
P of the detonation adiabatic curve. Point P is also weak detonation point.
Zel
′
'
dovich founded classic detonation theory [
6
]. In the topic
“
Shock Waves of
Condensed Media
[
7
], Dremin proved that in general under-pressure detonation is
not reachable using thermal dynamics and gas kinetics.
The impossibility of under-pressure detonation is discussed. Figure
2.7
shows
the relative positions of detonation adiabatic curve H with balance conditions and
detonation adiabatic curve ki
i
(k
i
is the intermediates with certain amount ratio). The
released energy is more if the subscript i of k
i
is larger. The adiabatic curve of k
0
equals the impact adiabatic curve of the original explosives.
”
Fig. 2.6 The relative
positions of Rayleigh line and
Hugoniot curve
