High-resolution simulations of particle-driven gravity currents are presented. The study concentrates on dilute flows with small density differences between particle-laden and clear fluid. Moreover, particles are considered which have negligible inertia, and which are much smaller than the smallest length scales of the buoyancy-induced fluid motion. The governing equations are integrated numerically with a high-order mixed spectral/spectral-element technique. In the analysis of the results, special emphasis is placed on the sedimentation and resuspension of the particles, and on their feedback on the flow dynamics. Resuspension is modeled as a diffusive flux of particles through the bottom boundary. The conditions under which turbidity currents may become self-sustaining through particle entrainment are investigated as a function of slope angle, current and particle size, and particle concentration.

1.
Bonnecaze
 
R.
,
Huppert
 
H.
, and
Lister
 
J.
,
1993
. “
Particle-driven gravity currents
.”
J. Fluid Mech.
,
250
, pp.
339
369
.
2.
Dade
 
W.
, and
Huppert
 
H.
,
1995
. “
A box model for nonentraining, suspension-driven gravity surges on horizontal surfaces
.”
Sedimentology
,
42
, pp.
453
471
.
3.
Gladstone
 
C.
, and
Woods
 
A.
,
2000
. “
On the application of box models to particle-driven gravity currents
.”
J. Fluid Mech.
,
416
, pp.
187
195
.
4.
Hogg
 
A.
,
Ungarish
 
M.
, and
Huppert
 
H.
,
2000
. “
Particle-driven gravity currents: asymptotics and box-model solutions
.”
Eur. J. Mech. B-Fluids
,
19
, pp.
139
165
.
5.
Ungarish
 
M.
, and
Huppert
 
H.
,
2000
. “
High-reynolds-number gravity currents over a porous boundary: shallow-water solutions and box-model approximations
.”
J. Fluid Mech.
,
418
, pp.
1
23
.
6.
Ha¨artel
 
C.
,
Meiburg
 
E.
, and
Necker
 
F.
,
2000
. “
Analysis and direct numerical simulation of the flow at a gravity-current head. part 1. Flow topology and front speed for slip and no-slip boundaries
.”
J. Fluid Mech.
,
418
, pp.
189
212
.
7.
Ha¨rtel
 
C.
,
Carlsson
 
F.
, and
Thunblom
 
M.
,
2000
. “
Analysis and direct numerical simulation of the flow at a gravity-current head. part 2: The lobe-and-cleft instability
.”
J. Fluid Mech.
,
418
, pp.
213
229
.
8.
Necker
 
F.
,
Ha¨artel
 
C.
,
Kleiser
 
L.
, and
Meiburg
 
E.
,
2002
. “
High-resolution simulations of particle-driven gravity currents
.”
Int. J. of Multiphase Flow
,
28
, pp.
279
300
.
9.
Necker, F., Ha¨artel, C., Kleiser, L., and Meiburg, E., accepted for publication. “Mixing and dissipation in particle-driven gravity currents.” J. Fluid Mech.
10.
Dietrich
 
W.
,
1982
. “
Settling velocity of natural particles
.”
Water Resources Res.
,
18
(
6
), pp.
1615
1626
.
11.
Normark
 
W.
,
Posamentier
 
H.
, and
Mutti
 
E.
,
1993
. “
Turbidite systems; state of the art and future directions
.”
Rev. of Geophys.
,
31
, pp.
91
116
.
12.
Blanchette, F., Strauss, M., Meiburg, E., Kneller, B., and Glinsky, M., 2005. “High-resolution numerical simulations of resuspending gravity currents: conditions for self-sustainment.” J. Geophys. Res., to appear.
13.
Parsons
 
J.
, and
Garci´a
 
M.
,
1998
. “
Similarity of gravity current fronts
.”
Phys. of Fluids
,
10
, pp.
3209
3213
.
14.
Shraiman
 
B.
, and
Siggia
 
E.
,
2000
. “
Scalar turbulence
.”
Nature
,
405
, pp.
639
646
.
15.
Blanchette, F., Piche, V., Meiburg, E., and Strauss, M., submitted, 2004. “Evaluation of a simplified approach simulating gravity currents over slopes of varying angles.” Computers & Fluids.
16.
Garci´a
 
M.
, and
Parker
 
G.
,
1993
. “
Experiments on the entrainment of sediment into suspension by a dense bottom current
.”
J. Geo. Res.
,
98
, pp.
4793
4807
.
17.
Torquato
 
S.
,
Truskett
 
T.
, and
Debenedetti
 
P.
,
2000
. “
Is random close packing of spheres well defined?
Phys. Rev. Lett.
,
84
, pp.
2064
2067
.
18.
Ha¨rtel
 
C.
,
Kleiser
 
L.
,
Michaud
 
M.
, and
Stein
 
C.
,
1997
. “
A direct numerical simulation approach to the study of intrusion fronts
.”
J. Eng. Math.
,
32
, pp.
103
120
.
19.
de Rooij
 
F.
, and
Dalziel
 
S.
,
2001
. “
Time and space resolved measurements of deposition under turbidity currents
.”
Spec. Publs. in. Ass. Sediment
,
31
, pp.
207
215
.
20.
Garci´a
 
M.
,
1994
. “
Depositional turbidity currents laden with poorly sorted sediment
.”
J. Hydr. Engr.
,
120
, pp.
1240
1263
.
21.
Huppert
 
H.
, and
Simpson
 
J.
,
1980
. “
The slumping of gravity currents
.”
J. Fluid Mech.
,
99
, pp.
785
799
.
22.
Garci´a
 
M.
,
1993
. “
Hydraulic jumps in sediment-driven bottom currents
.”
J. Hydr. Engr.
,
119
, pp.
1094
1117
.
This content is only available via PDF.
You do not currently have access to this content.