Abstract

The goal of the study is to identify optimal breakwater designs to be placed on the banks of various water bodies in coastal Louisiana, to prevent the coastal erosion. Coastal erosion is a significant concern for Louisiana's wavy coastline. The loss of coastal wetlands is threatening the environment and the economic development. One of the ways to prevent coastal erosion and wetland losses is by using breakwaters designed to reduce the wave energy and change the transport of sediments brought by the waves. The objective of this research is to analyze the turbulent characteristics around specially designed three-dimensional (3D) breakwaters, and its impact on sediment deposition under coastal wave actions. Both computational fluid dynamics (CFD) simulations and experimental measurements were conducted. In order to validate the CFD models used for this study, the simulation results were compared to data measured from a scale-down experiment. Once the validity of the CFD models has been confirmed on three miniature panels, namely, a solid panel, a panel with three holes, and a panel with eight holes, the simulations were scaled up to the actual size of the designed breakwater panels for tests. The breakwater designs aim to allow sediment pass through the holes, to deposit sediment at target areas, and to reduce wave actions. There were three different panel-design cases simulated in this study. The results of 3D CFD simulations of these panels were compared and analyzed to determine the performance of each design in terms of wave reduction and sediment retention.

References

References
1.
Couvillion
,
B. R.
,
Barras
,
J. A.
,
Steyer
,
G. D.
,
Sleavin
,
W.
,
Fischer
,
M.
,
Beck
,
H.
,
Trahan
,
N.
,
Griffin
,
B.
, and
Heckman
,
D.
,
2011
, “
Land Area Change in Coastal Louisiana From 1932 to 2010
,” U.S. Geological Survey Scientific Investigations Map 3164, Reston, VA.
2.
Dardis
,
D.
, and
Pat
,
P.
,
2018
, “
Louisiana's Oil
,” Wetlands and Coastal Erosion, Hammond, LO, accessed Apr. 24, 2018, http://www2.southeastern.edu/orgs/oilspill/wetlands.html
3.
Smith
,
K.
,
2012
, “
Paleoecological Study of Coastal Marsh in the Chenier Plain
,”
Investigating the Diatom Composition of Hurricane-Deposited Sediments and a Diatom Based Quantitative Reconstruction of Sea-Level Characteristics
,
University of Florida
,
Gainesville, FL
.
4.
Titus
,
J. G.
,
1985
, “
Potential Impacts of Sea Level Rise on the Beach at Ocean City, Maryland
,” U.S. Environmental Protection Agency, Office of Policy Planning and Evaluation, Washington, DC, Report No. 230-10-85-013.
5.
Leonardi
,
N.
,
Neil
,
K. G.
, and
Sergio
,
F.
,
2016
, “
A Linear Relationship Between Wave Power and Erosion Determines Salt-Marsh Resilience to Violent Storms and Hurricanes
,”
Proc. Natl. Acad. Sci.
,
113
(
1
), pp.
64
68
.10.1073/pnas.1510095112
6.
White
,
C. M.
,
1940
, “
The Equilibrium of Grains on the Bed of a Stream
,”
Proc. R. Soc. A
,
174
(
958
), pp.
322
338
.10.1098/rspa.1940.0023
7.
Hatton
,
R.
,
DeLaune
,
R.
, and
Patrick
,
W.
,
1983
, “
Sedimentation, Accretion, and Subsidence in Marshes of Barataria Basin, Louisiana
,”
Limnol. Oceanogr.
,
28
(
3
), pp.
494
502
.10.4319/lo.1983.28.3.0494
8.
Hughes
,
S.
,
2007
, “
Estimation of Overtopping Flow Velocities on Earthen Levees Due to Irregular Waves
,” U.S. Army Engineer Research and Development Center, Vicksburg, MS.
9.
Hardaway
,
C. S.
, and
James
,
R. G.
,
2010
, “
A Brief History of Headland Breakwaters for Shore Protection in Chesapeake Bay, USA
,”
Shore Beach
,
78
(
4
), pp.
1
9
.
10.
Gergely
,
T. T.
,
Sándor
,
B.
, and
Nils
,
R.
,
2017
, “
3D CFD Modeling of Local Scouring, Bed Armoring and Sediment Deposition
,”
Water
,
9
(
1
), p.
56
.10.3390/w9010056
11.
Chechko
,
V.
,
Sokolov
,
A.
,
Chubarenko
,
B.
,
Dikii
,
D.
, and
Topchaya
,
V.
,
2015
, “
Dynamics of Sediments Disposed in the Marine Coastal Zone Near the Vistula Lagoon Inlet, South-Eastern Part of the Baltic Sea
,”
Baltica
,
28
(
2
), pp.
189
199
.10.5200/baltica.2015.28.16
12.
Cheng
,
H.
, and
Jiri
,
M.
,
2014
, “
Enhancing Sedimentation and Trapping Sediment With a Bottom Grid Structure
,”
J. Environ. Eng.
,
140
(
1
), pp.
21
29
.10.1061/(ASCE)EE.1943-7870.0000774
13.
ANSYS
,
2013
, “
ANSYS Fluent Theory Guide
,” ANSYS, Canonsburg, PA.
14.
Morsi
,
S. A.
, and
Alexander
,
A. J.
,
1972
, “
An Investigation of Particle Trajectories in Two-Phase Flow Systems
,”
J. Fluid Mech.
,
55
(
2
), pp.
193
208
.10.1017/S0022112072001806
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