The East Sea surrounded by Korea, Japan and Russia is one of the most vulnerable places to tsunam... more The East Sea surrounded by Korea, Japan and Russia is one of the most vulnerable places to tsunami attacks in the world. A number of tsunamis have been occurred during last decades in the region. In special, the middle areas of the eastern coast of the Korean Peninsula have been damaged due to the Central East Sea Tsunami occurred in 1983. Thus, tsunami hazard mitigation becomes an important issue at those coastal communities. The countermeasures against unexpected tsunami attacks are not sufficient because the government policy of Korea generally focused on not preventing but recovering. In this study, a hazard map based on the field survey and tsunami evacuation plan is developed to mitigate tsunami damage at Imwon port, which was severely damaged during the 1983 Central East Sea Tsunami.
The linear shallow-water equations have been used frequently to simulate transoceanic propagation... more The linear shallow-water equations have been used frequently to simulate transoceanic propagation of tsunamis instead of the linear Boussinesq equations. In previous studies, the physical dispersion is compensated by using the numerical dispersion generated from the leap-frog finite difference scheme. However, the linear Boussinesq equations can be directly solved because computer technique has been improved dramatically. In this study, a new finite difference scheme is proposed to discretize the linear Boussinesq equations. The newly developed model is applied to propagation of a Gaussian hump over a constant water depth. The model is then verified by comparing predicted results with analytic solutions. Predicted results agree well with analytical solutions. The model can be directly applied to simulation of transoceanic propagation of tsunamis.
This thesis contains two different topics: 1) Wave energy resource assessments, characterizations... more This thesis contains two different topics: 1) Wave energy resource assessments, characterizations, and classifications for US coastal waters, 2) Numerical studies for three-dimensional circulation during coastal upwelling favorable winds on the inner shelf near Point Sal, California. Ocean waves are a largely abundant and untapped renewable source of energy with limited environmental impact and high energy density. Although ocean waves have significant energy potential, the technology is in early stages of development due to high costs from lower conversion efficiencies as well as risks to operations, maintenance and survival. This study characterizes and classifies the wave energy resource by performing a comprehensive resource assessment of the wave energy for the US. The work for this portion includes three parts. The first part focuses on describing the wave energy resource parameters or metrics for characterization, e.g., wave energy potential, dominant frequency, directional and t...
Classification systems for wave energy resources and wave energy converter (WEC) technologies cou... more Classification systems for wave energy resources and wave energy converter (WEC) technologies could provide similar benefits to those for the wind energy industry: resource classification facilitating reconnaissance studies and project planning at both regional and national scales; and WEC classification streamlining and reducing costs of WEC device design and manufacturing. In the present study, a classification system for U.S. wave resources is used to investigate the feasibility of WEC classification. Wave spectra inputs from three wave energy resource classes delineated in this system are used to derive distributions of optimized WEC design scaling factors, as well as WEC design responses. Preliminary results indicate that a single standard WEC design class could serve within a given resource class, and corresponding regional wave climate, due to distinct wave energy distributions and concentrations of energy within partitioned period bands for each resource class. The WEC respo...
The submission includes wave resource classification reports, summary of classification statistic... more The submission includes wave resource classification reports, summary of classification statistics and regional trends, and data files with classification statistics for selected sites for extreme significant wave height. Two conference papers were uploaded that include classification metrics and geographic distributions for US coastal waters. These conference papers are: Neary, V.S., Coe, R.G., Cruz, J., Haas, K., Bacelli, G., Debruyne, Y., Ahn, S., Nevarez, V. (2017) Classification systems for wave energy resources and WEC technologies. Proceedings of 12th European Wave and Tidal Energy Conference Series (EWTEC 2017), Cork, Ireland, August 27-September 1, 2017 Haas, K., Ahn, S., Neary, V.S., and S. Bredin (2017) Development of a wave energy classification system. Proceedings of the 5th Marine Energy Technology Symposium (METS2017), Washington, D.C., May 1-3, 2017
The East Sea surrounded by Korea, Japan and Russia is one of the most vulnerable places to tsunam... more The East Sea surrounded by Korea, Japan and Russia is one of the most vulnerable places to tsunami attacks in the world. A number of tsunamis have been occurred during last decades in the region. In special, the middle areas of the eastern coast of the Korean Peninsula have been damaged due to the Central East Sea Tsunami occurred in 1983. Thus, tsunami hazard mitigation becomes an important issue at those coastal communities. The countermeasures against unexpected tsunami attacks are not sufficient because the government policy of Korea generally focused on not preventing but recovering. In this study, a hazard map based on the field survey and tsunami evacuation plan is developed to mitigate tsunami damage at Imwon port, which was severely damaged during the 1983 Central East Sea Tsunami.
The linear shallow-water equations have been used frequently to simulate transoceanic propagation... more The linear shallow-water equations have been used frequently to simulate transoceanic propagation of tsunamis instead of the linear Boussinesq equations. In previous studies, the physical dispersion is compensated by using the numerical dispersion generated from the leap-frog finite difference scheme. However, the linear Boussinesq equations can be directly solved because computer technique has been improved dramatically. In this study, a new finite difference scheme is proposed to discretize the linear Boussinesq equations. The newly developed model is applied to propagation of a Gaussian hump over a constant water depth. The model is then verified by comparing predicted results with analytic solutions. Predicted results agree well with analytical solutions. The model can be directly applied to simulation of transoceanic propagation of tsunamis.
This thesis contains two different topics: 1) Wave energy resource assessments, characterizations... more This thesis contains two different topics: 1) Wave energy resource assessments, characterizations, and classifications for US coastal waters, 2) Numerical studies for three-dimensional circulation during coastal upwelling favorable winds on the inner shelf near Point Sal, California. Ocean waves are a largely abundant and untapped renewable source of energy with limited environmental impact and high energy density. Although ocean waves have significant energy potential, the technology is in early stages of development due to high costs from lower conversion efficiencies as well as risks to operations, maintenance and survival. This study characterizes and classifies the wave energy resource by performing a comprehensive resource assessment of the wave energy for the US. The work for this portion includes three parts. The first part focuses on describing the wave energy resource parameters or metrics for characterization, e.g., wave energy potential, dominant frequency, directional and t...
Classification systems for wave energy resources and wave energy converter (WEC) technologies cou... more Classification systems for wave energy resources and wave energy converter (WEC) technologies could provide similar benefits to those for the wind energy industry: resource classification facilitating reconnaissance studies and project planning at both regional and national scales; and WEC classification streamlining and reducing costs of WEC device design and manufacturing. In the present study, a classification system for U.S. wave resources is used to investigate the feasibility of WEC classification. Wave spectra inputs from three wave energy resource classes delineated in this system are used to derive distributions of optimized WEC design scaling factors, as well as WEC design responses. Preliminary results indicate that a single standard WEC design class could serve within a given resource class, and corresponding regional wave climate, due to distinct wave energy distributions and concentrations of energy within partitioned period bands for each resource class. The WEC respo...
The submission includes wave resource classification reports, summary of classification statistic... more The submission includes wave resource classification reports, summary of classification statistics and regional trends, and data files with classification statistics for selected sites for extreme significant wave height. Two conference papers were uploaded that include classification metrics and geographic distributions for US coastal waters. These conference papers are: Neary, V.S., Coe, R.G., Cruz, J., Haas, K., Bacelli, G., Debruyne, Y., Ahn, S., Nevarez, V. (2017) Classification systems for wave energy resources and WEC technologies. Proceedings of 12th European Wave and Tidal Energy Conference Series (EWTEC 2017), Cork, Ireland, August 27-September 1, 2017 Haas, K., Ahn, S., Neary, V.S., and S. Bredin (2017) Development of a wave energy classification system. Proceedings of the 5th Marine Energy Technology Symposium (METS2017), Washington, D.C., May 1-3, 2017
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