Environmental Engineering Reference
In-Depth Information
Ta b l e A . 5
Conversion factors in formulas for transport coefficients.
Number Formula
C
Units
10
5
cm
2
/s
K
in cm
2
/(V s),
T
in K
1
D
D
CKT
8.617
1cm
2
/s
K
in cm
2
/(V s),
T
in eV
11 604 cm
2
/(V s)
D
in cm
2
/s,
T
in K
2
K
D
CD
/
T
1cm
2
/(V s),
D
in cm
2
/s,
T
in eV
C
p
T
/
10
21
cm
2
/s
σ
1
in Å
2
,
N
in cm
3
,
T
in K,
3
D
D
μ
/(
N
σ
1
)
4.617
μ
in amu.
10
19
cm
3
,
1.595 cm
2
/s
σ
1
in Å
2
,
N
D
2.687
T
in K,
μ
in amu
171.8 cm
2
/s
σ
1
in Å
2
,
N
10
19
cm
3
,
D
2.687
T
in eV,
μ
in amu
68.1115 cm
2
/s
σ
1
in Å
2
,
N
10
19
cm
3
,
D
2.687
T
,
μ
in emu
7338 cm
2
/s
σ
1
in Å
2
,
N
10
19
cm
3
,
D
2.687
T
in eV,
μ
in emu
C
(
p
T
σ
1
)
1
10
4
cm
2
/(V s)
σ
1
in Å
2
,
N
10
19
cm
3
,
4
K
D
μ
N
1.851
D
2.687
T
in
K
,
μ
in amu
171.8 cm
2
/(V s)
σ
1
in Å
2
,
N
10
19
cm
3
,
D
2.687
T
in eV,
μ
in amu
10
5
cm
2
/(V s)
σ
1
in Å
2
,
N
10
19
cm
3
,
7.904
D
2.687
T
in
K
,
μ
in emu
7338 cm
2
/(V s)
σ
1
in Å
2
,
N
10
19
cm
3
,
D
2.687
T
in eV,
μ
in emu
C
p
T
/
m
/
10
4
W/(cmK)
T
in K,
m
in amu,
σ
2
in Å
2
5
D
σ
2
1.743
10
5
W/(cmK)
T
in K,
m
in emu,
σ
2
in Å
2
7.443
C
p
Tm
/
10
5
g/(cms)
T
in K,
m
in amu,
σ
2
in Å
2
6
η
D
σ
2
5.591
1 The Einstein relation (4.38) for the diffusion coefficient of a charged particle in a gas
D
KT
/
e
,
where
D
and
K
are the diffusion coefficient and mobility of a charged particle and
T
is the gas
temperature.
2 The Einstein relation (4.38) for the mobility of a charged particle in a gas
K
D
eD
/
T
.
3 The diffusion coefficient of an
atomic
parti
cle
in a gas in the first Chapman-Enskog
approximation (4.53),
D
D
3
p
2
D
π
T
/
μ
/(16
N
σ
1
), where
T
is the gas temperature,
N
is the number
density of gas a
to
ms or molecules,
μ
is the reduced mass of a colliding particle and a gas atom or
1
is the average cross section of collision.
4 The mobil
ity of a c
harge
d p
article in a gas in the first Chapman-Enskog approximation (4.21),
K
molecule, and
σ
3
e
p
2
1
); the notation is the same as above.
5 The g
as th
ermal conductivity in the first Chapman-Enskog ap
pro
ximation (4.54),
D
π
/(
T
μ
)/(16
N
σ
25
p
π
D
T
/
(32
p
m
2
is the average cross section of
collision between gas atoms or molecules; other notation is the same as above.
6 The gas viscosity in the first Chapman-Enskog approximation (4.56),
σ
2
), where
m
is the mass of the atom or molecule and
σ
5
p
η
D
π
Tm
/(24
σ
2
); the
notation is the same as above.
