Untitled - Aerobib - Universidad Politécnica de Madrid

122 CHAPTER 5. STRUCTURE OF THE COMBUSTION WAVES
zone of negligible thickness compared to that of the detonation wave, where no appreciable
chemical reaction occurs. After the shock wave the combustion is initiated. The
gases expand and accelerate and the pressure decreases. Temperature rises due to the
reaction. For Chapman-Jouguet detonation and slightly strong detonations, the maxi-
20
18
T/T 1
16
14
12
10
8
6
D
C
ε =0.3
E
ε =1
J
K
ε =0.7
E‘
4
2
0
ε =0
Trayectory through shock wave
P
0.2 0.4 0.6 0.8 1.0
τ /τ 1
Figure 5.3: Hugoniot diagram in variables (T, τ).
15
50
1.0
13
40
C
P/P 1
K
J
0.8
11
30
J
0.6
T/T 1
9
P/P 1
20
T/T 1
J
0.4
τ/τ 1
7
10
C
C
τ/τ 1
0.2
5
0.0 0.2 0.4 0.6 0.8 1.0
Figure 5.4: Typical values of T , p and τ in a Chapman-Jouguet detonation as a function of
the fraction of burnt gases.
ε