TY - JOUR
T1 - Numerical study of run-up oscillations over fringing reefs
AU - Peláez-Zapata, D. S.
AU - Montoya, Rubén D.
AU - Osorio, Andrés F.
N1 - Funding Information:
The authors are grateful to the Colombian Administrative Department of Science, Technology, and Innovation (Colcien-cias) project ‘‘Extreme Oceanic Events in the Insular Coastal Ecosystems of the Colombian Pacific and Caribbean’’ (Eventos Oceánicos Extremos en Ecosistemas Costeros Insulares del Pacífico y el Caribe Colombianos) and the research fellowship ‘‘Wave modeling produced by extreme events in Colombian island regions in the Caribbean and Pacific’’ (Modelación de oleaje producido por eventos extremos en zonas insulares del Caribe y Pacífico colombianos) for financial support. We are also grateful to Dr. Zeki Demirbilek from Coastal and Hydraulics Laboratory, U.S. Army Engineer Research and Development Center of the U.S. Army Corp of Engineers (CHL/ERDC/USACE) for providing data from the ‘‘Laboratory Study of Wind Effect on Run-up over Fringing Reefs.’’ The authors thank the anonymous reviewers for their valuable comments that helped to improve this work.
Publisher Copyright:
© Coastal Education and Research Foundation, Inc. 2018.
PY - 2018/9/1
Y1 - 2018/9/1
N2 - Peláez-Zapata, D.S.; Montoya, R.D., and Osorio, A.F., 2018. Numerical study of run-up oscillations over fringing reefs. This work presents a numerical study of run-up oscillations over a typical fringing reef profile at the laboratory scale. The nonhydrostatic SWASH model was calibrated and validated using experimental data of free surface elevation for eight gauges and run-up oscillations. The model shows a high sensitivity to variations in the parameters of bottom friction and horizontal mixing length. A process of calibration found the optimal values to be 0.014 s m-1/3 and 0.01 m, respectively. With these values, the model is good at reproducing bulk run-up parameters such as the mean run-up period (r2 = 0.93), sea-swell significant run-up (r2 = 0.93), and infragravity significant run-up (r2 = 0.88). The ratio between the infragravity and sea-swell run-up is highly dependent on the surf similarity parameter. For dissipative and intermediate conditions, the run-up is mainly dominated by low-frequency or infragravity oscillations, whereas for reflective conditions, high-frequency or sea-swell oscillations become more important. The results show that the run-up spectrum at high frequencies is proportional to f-4. The energy level at high frequencies is apparently independent of the offshore wave conditions and the width of the reef flat. However, the depth of the reef crest seems to be the most influential variable on the high-frequency energy. A parametric equation that depends on both the energy level at high frequency and a function of the run-up period was obtained to analyze the spectral characteristics of the wave run-up. This equation can be considered a first approach to a general parameterization of the run-up spectrum for reef zones, which can be useful in coastal engineering applications, such as predicting both the run-up height and frequency, spectral response of sediment transport in the swash zone, and coupling with spectral wave models.
AB - Peláez-Zapata, D.S.; Montoya, R.D., and Osorio, A.F., 2018. Numerical study of run-up oscillations over fringing reefs. This work presents a numerical study of run-up oscillations over a typical fringing reef profile at the laboratory scale. The nonhydrostatic SWASH model was calibrated and validated using experimental data of free surface elevation for eight gauges and run-up oscillations. The model shows a high sensitivity to variations in the parameters of bottom friction and horizontal mixing length. A process of calibration found the optimal values to be 0.014 s m-1/3 and 0.01 m, respectively. With these values, the model is good at reproducing bulk run-up parameters such as the mean run-up period (r2 = 0.93), sea-swell significant run-up (r2 = 0.93), and infragravity significant run-up (r2 = 0.88). The ratio between the infragravity and sea-swell run-up is highly dependent on the surf similarity parameter. For dissipative and intermediate conditions, the run-up is mainly dominated by low-frequency or infragravity oscillations, whereas for reflective conditions, high-frequency or sea-swell oscillations become more important. The results show that the run-up spectrum at high frequencies is proportional to f-4. The energy level at high frequencies is apparently independent of the offshore wave conditions and the width of the reef flat. However, the depth of the reef crest seems to be the most influential variable on the high-frequency energy. A parametric equation that depends on both the energy level at high frequency and a function of the run-up period was obtained to analyze the spectral characteristics of the wave run-up. This equation can be considered a first approach to a general parameterization of the run-up spectrum for reef zones, which can be useful in coastal engineering applications, such as predicting both the run-up height and frequency, spectral response of sediment transport in the swash zone, and coupling with spectral wave models.
KW - numerical modeling
KW - run-up spectrum
KW - SWASH model
KW - Wave run-up
UR - http://www.scopus.com/inward/record.url?scp=85046125900&partnerID=8YFLogxK
U2 - 10.2112/JCOASTRES-D-17-00057.1
DO - 10.2112/JCOASTRES-D-17-00057.1
M3 - Artículo
AN - SCOPUS:85046125900
VL - 34
SP - 1065
EP - 1079
JO - Journal of Coastal Research
JF - Journal of Coastal Research
SN - 0749-0208
IS - 5
ER -