Environmental Engineering Reference
In-Depth Information
The Equation
Substituting
ϕ
(
x
)=
1 into Eq. (5.49), we have
u
(
x
,
t
)=
u
1
(
x
,
t
)+
u
2
(
x
,
t
)+
u
3
(
x
,
t
)
,
where
t
e
−
u
1
(
x
,
t
)=
2
τ
0
,
τ
0
I
0
b
2
d
x
+
At
1
2
A
1
2
t
e
−
2
u
2
(
x
,
t
)=
2
τ
0
(
At
)
−
(
x
−
ξ
)
ξ
,
x
−
At
t
2τ
0
I
e
−
u
3
(
x
,
t
)=
I
1
b
2
d
x
+
At
1
8
A
t
t
2τ
0
e
−
2
=
b
(
At
)
−
(
x
−
ξ
)
ξ
.
2
0
τ
x
−
At
2
2
(
)
−
(
−
ξ
)
At
x
By Eq. (5.47), we have
2
1
τ
0
1
t
e
−
u
2
(
x
,
t
)=
−
.
Also,
I
1
b
2
d
x
+
At
1
8
A
t
2
I
=
b
(
At
)
−
(
x
−
ξ
)
ξ
2
0
τ
x
−
At
2
2
(
At
)
−
(
x
−
ξ
)
t
τ
0
2
t
τ
0
4
t
τ
0
6
1
8
1
384
1
46080
=
+
+
+
···
t
2
2
t
2
4
t
2
6
1
2!
1
4!
1
6!
=
+
+
+
··· .
τ
0
τ
0
τ
0
i.e.
2
e
τ
0
t
1
t
t
e
−
τ
0
=
+
=
+
.
ch
2
τ
0
2
1
I
2
Hence,
2τ
0
ch
1
t
τ
0
e
−
t
1
2
−
t
t
2τ
0
e
−
e
−
u
3
(
x
,
t
)=
τ
0
−
=
+
.
2
2
Search WWH ::
Custom Search