Environmental Engineering Reference
In-Depth Information
s
1
q
0
1
q
1
#
1
#
0
¼
ð
P
1
P
0
Þ
s
1
q
1
1
q
2
#
2
#
1
¼
ð
P
2
P
1
Þ
ection waves are opposite from the incident ones, the
incident waves are positive, the re
Because the direction of re
fl
fl
ection waves are negative, and
#
1
¼
#
2
¼
0, so
1
q
0
1
q
1
1
q
1
1
q
2
ð
P
1
P
0
Þ
¼ P
2
P
1
ð
Þ
or
¼ P
2
P
1
P
1
P
0
q
0
q
0
q
1
q
1
q
2
1
ð
Þ
1
ð
2
:
95
Þ
The adiabatic function of shock waves is below.
P
1
P
2
k
þ
1
k
þ
1
k
1
P
0
þ
1
k
1
P
1
þ
1
q
1
q
0
¼
q
2
q
1
¼
;
P
1
P
0
P
2
P
1
k
þ
1
k
þ
1
k
1
þ
k
1
þ
Substitute the adiabatic function into Eq.
2.95
2
2 P
1
P
0
ð
Þ
q
1
k
½
ð
1
Þ
P
1
þ
k
þ
ð
1
Þ
P
0
2
2 P
2
P
1
ð
Þ
¼
q
1
k
þ
½
ð
Þ
P
2
þ
k
ð
Þ
P
1
1
1
2
1
¼
#
The super pressure of incident waves is
D
P
1
¼ P
1
P
0
And the super pressure of re
fl
ection waves is
D
P
2
¼ P
2
P
0
The above equation is changed to
2
D
P
2
ð
D
P
2
D
P
1
Þ
2kP
0
¼
ð
k
1
Þ
D
P
1
þ
ð
k
þ
1
Þ
D
P
2
þ
k
þ
ð
1
Þ
P
2
þ
k
ð
1
Þ
D
P
1
þ
2kP
0