Environmental Engineering Reference
In-Depth Information
Fig. 5.8
Transient solution
for transport equation with
degradation; dimensionless
space variable x and
dimensionless concentration
y for
Pe ¼
100 and
Da
2
¼
1,
for
c
0
¼ c
in
=
2
¼
0
:
5
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0
0.2
0.4
0.6
0.8
1
Distance
x
[-]
the deviation from the steady state is relatively moderate but increasing. The plot
was obtained by using the M-file
'analtransnodim.m'
with appropriate parameters.
Figure
5.8
shows a typical behavior when
c
0
is not equal to zero. In that case,
both terms in the formulae (
5.29
) and (
5.30
) have to be considered. The decline of
concentrations from one line to the other on the right side of the figure illustrates the
decay of the material, which was initially present in the system. Increasing
concentrations on the left side stem from the advancing front.
For analytical solutions of decay chains see chap. 10.4. For multi-species
transport of decay-chains see corresponding references in that chapter.
References
Anderson RF, Bopp RF, Buesseler KO, Biscaye PE (1988) Mixing of particles and organic
constituents in sediments from the continental shelf and slope off cape cod: SEEP-1 results.
Cont Shelf Res 8(5-7):925-946
Appelo CA, Postma D (1993) Geochemistry, groundwater and pollution. Balkema, Rotterdam,
p 536
Henderson GM, Lindsay FN, Slowey NC (1999) Variation in bioturbation with water depth on
marine slopes: a study on the little Bahamas bank. Mar Geol 160:105-118
Walker A, Brown PA (1983) Measurement and prediction of chlorsulforon persistence in soil. Bull
Environ Contam Toxicol 30:365-372
Wexler EJ (1992) Analytical solutions for one-, two-, and three-dimensional solute transport in
groundwater systems with uniform flow, Techniques of Water-Resources Investigations of the
United States Geological Survey, Book 3, Chapter B7, p 190
