COULWAVE simulation of waves generated by Hurricane Katrina entering the 17th Street Canal of New Orleans.

Research Projects

Numerical and Physical Modeling of Nearshore Tsunami Evolution

The goals of these projects focus on developing sufficient scientific knowledge and appropriate engineering tools on which to base comprehensive tsunami mitigation plans and communicate this information effectively to decision makers, the emergency planning community and the public.

"NEESR-SG: TSUNAMOS: A Validated, Multi-Scale Tsunami Model for Hybrid Numerical-Experimental Simulation." Funded by the National Science Foundation, September 2006 to September 2009. PI: P. Lynett. Co-PI's: Liu, A. Mercado, M. Teng, C. von Hillebrandt-Andrade.

"Tsunami Impacts in the Gulf of Oman." Funded by Lighthouse R & D Enterprises, Inc., September 2007 to September 2008. PI: P. Lynett, part of a larger effort led by S. DiMarco.

"NEESR: Tsunami Induced Coherent Structures and their Impact on our Coastal Infrastructure." Funded by the National Science Foundation, September 2011 to September 2014. PI: D. Foster. Co-PI's: T. Hsu, P. Lynett. See the NSF award page for details about the project

"Data Generation for Determination of Safe Depths near Ports, Harbors, and Marinas During Tsunamis." Funded by the California Emergency Management Agency (CalEMA), August 2012 to August 2013. PI: P. Lynett.

"Simulation of Complex Tsunami Processes for Use in Hazard Mapping." Funded by the California Geological Survey, September 2012 to September 2021. PI: P. Lynett.

"Tsunami Modeling in Support of the USGS Application for Risk Reduction Project." Funded by the USGS, September 2012 to September 2014. PI: P. Lynett.

"Simulation Confidence in Tsunami-Driven Overland Flow." Funded by the PEER, May 2014 to May 2015. PI: P. Lynett.

"Nonlinear Long Wave Amplification in the Shadow Zone of Offshore Islands." Funded by the National Science Foundation, September 2015 to September 2019. PI: C. Synolakis. Co-PI: P. Lynett. See the NSF award page for details about the project

"Recording Tsunami Impacts from the Taan Fjord, Alaska Landslide of October 17th, 2015." Funded by the National Science Foundation, September 2016 to September 2018. PI: P. Lynett. See the NSF award page for details about the project

"Tsunami Debris: Simulating Hazard and Loads." Funded by the PEER, January 2018 to May 2021. PI: P. Lynett.

Creation of a Hydraulic-Flow-Driven Wavetank

Our ultimate aim is to develop a new experimental device which would permit the study of multi-scale and vertically-variable oceanographic flows. Specific issues, such as nonlinear wave-current interaction over variable bathymetry, vertical mixing in the presence of waves and currents, surface and internal wave interaction, and any number of additional problems that might include nonlinear long waves, short waves, uniform and sheared currents, and vertical density stratification can be investigated. The platform on which these studies will be launched is a controlled hydraulic flow system. Both upstream and downstream flume boundaries are composed of an adjustable set of vertical baffles, or chambers. Each chamber is connected to an individual pump control system, such that the vertical distribution of flow is entirely controllable. In such a system, any arbitrary flow can be reasonably created, and different sets of baffles can be connected to different reservoirs to create vertical density profiles..

"No More Moving Walls: A Wave-Maker Concept for the Study of Oceanographic Flows." Internal funding by USC.

"Development of a High-Control Jet-Array Wavemaker." Funded by the National Science Foundation, September 2014 to September 2016. PI: P. Lynett. See NSF award page for more details.

Large-Scale, Multi-Physics Coastal Modeling

The broad aim of this project is to develop a coupled, hybrid hydrodynamic computational model for simulation and prediction of complex water wave processes from the deep ocean to the shoreline. The model will be physically comprehensive, with total domain scales on the order of hundred's of kilometers, yet with a nearshore grid resolution less than a meter. To include this great range of scales, a number of diverse hydrodynamic models, with various but overlapping physical and practical constraints, will be integrated to create a hybrid hydrodynamic software tool.

"Collaborative Research: ITR-(ASE+EVS)-(dmc+sim): Coastal Modeling and Management." Funded by the National Science Foundation, September 2004 to September 2008, $395,000. PI: P. Lynett. co-PI: V. Sarin.

In order for such models to have widespread adoption and use, a cohesive community organization, centered around shared research through cyber-infrastructure, must exist. Creation of the Virtual Institute for Multi-scale Inundation Studies (VIMIS) represents the initial effort towards development of such an organization.

"A Virtual Organization to Develop Complex, Multi-scale Models Addressing the Impact of Inundation on Natural and Man-made Environments." Funded by the National Science Foundation, September 2007 to September 2009. PI: C. Pancake. Co-PI's: H. Yeh, F. Williams, T. Dalrymple, P. Lynett. See NSF award page for more details.

Other funded projects include:

"Faster than Real-Time Coastal Wave Visualization with a Phase-Resolving Boussinesq-type Model." Funded by the Office of Naval Research, May 2014 to May 2016. PI: P. Lynett.

"Assimilation of Wave Imaging Radar Observations for Real-time Wave-by-Wave Forecasting." Funded by the DOE, December 2014 to December 2016. PI: M. Haller (OSU), P. Lynett co-PI.

"NHERI: Computational Modeling and Simulation Center." Funded by the National Science Foundation, September 2016 to September 2021. PI: s. Mahin (Berkeley), Lynety co-I. See the NSF award page for details about the project

"Interactive Augmented Reality for Stakeholder Education of Coastal Hazards." Funded by the National Science Foundation, September 2019 to September 2022. PI: P. Lynett. See the NSF award page for details about the project

Estuary Mixing Processes

This work investigates the formation and development of large, two-dimensional coherent structures in coastal flows and their prediction using two-dimensional coastal numerical models.

"Laboratory studies of mixing processes in estuaries and coastal flows on the Texas coast." Funded by the Texas NOAA Sea Grant College Program, March 2006 to February 2008, $305,351. PI: S. Socolofsky. Co-PIs: K.-A. Chang and P. Lynett.

"Long Waves in Riverine Estuaries." Funded by the National Science Foundation, September 2018 to September 2021. PI: H. Yeh (OSU). Co-PI: P. Lynett. See the NSF award page for details about the project

Wave-Current Interactions

The hydrodynamics near a river mouth or inlet are among the most complex in the nearshore, involving strong current interactions, nonlinear free surface waves, and mixing of fresh and salt water. These physics lead to large shear, in both the horizontal and vertical directions, and thus any modeling approach must be capable of capturing the resulting turbulent motions - both small and large scale motions - in order to predict mixing and transport. While use of fully 3D approaches with proper turbulent closure, such as Large Eddy Simulation (LES), represents an extremely high fidelity method of simulating the "complete" physical problem, their correct application on practical, operational-scale domains is a vision of the future. To examine such problems efficiently, one must make use of an approximate approach. It is the goal of the research proposed here to further develop such an approach, but still include all the important hydrodynamics with minimal averaging. The proposed method of analysis is numerical, employing a new depth-integrated, Boussinesq-type flow framework. This modeling approach permits the complete physical coupling of wind waves in the coastal zone with any source of current in the time and space (phase-resolving) domain. The unique aspects of this new model centers on the fact that bottom-friction-driven turbulence, and the resulting vertical and horizontal vorticity, is explicitly included.

"Efficient Non-Hydrostatic Modeling of Rotational, Turbulent, Dispersive, and Variable-Density Flows in the Vicinity of River Mouths and Inlets." Funded by the Office of Naval Research, October 2009 to October 2012. PI: P. Lynett.

"Development of a "Spot-Application" Tool for Rapid, High-Resolution Simulation of Wave-Driven Nearshore Hydrodynamics." Funded by the Office of Naval Research, June 2013 to June 2015. PI: P. Lynett.

"Development of an Immersive Coastal Hydrodynamic Simulation Environment." Funded by the Office of Naval Research, September 2017 to September 2020. PI: P. Lynett.

Surge and Wave Modeling and Interaction with Structures

This research aims towards developing a better understanding of nearshore wave behavior, particulary for wave interaction with coastal structures such as breakwaters, levees, and seawalls. This increased understanding should then be directly applied to design procedure and guidelines.

"Boussinesq Modeling of Directional Spectra and Surge Overtopping of Levees." Funded by the U.S. Army Corps of Engineers, September 2006 to August 2007. PI: P. Lynett. co-PI: J. Irish.

"Development Of A Levee Overtopping Lookup Database Using Boussinesq Simulations." Funded by the U.S. Army Corps of Engineers, March 2007 to March 2008. PI: P. Lynett.

"Numerical Tool Development in Support of Risk-Based Engineering Models." Funded by the U.S. Army Corps of Engineers, June 2007 to January 2008. PI: P. Lynett.

"Development of GuideSpecs for Tsunami Loads on Bridges." Funded by the PEER, April 2015 to May 2018. PI: P. Lynett.

"Wave, Surge, and Tsunami Overland Hazard, Loading and Structural Response for Developed Shorelines." Funded by the National Science Foundation, July 2017 to July 2021. PI: A. Kennedy (Notre Dame). Co-PI: P. Lynett. See the NSF award page for details about the project

Modeling of Tsunami Impacts near Nuclear Reactors

Dr. Lynett has worked closely with the Nuclear Regulatory Commission's (NRC's) New Reactor group on review of site safety documents over the past 3 years, including direct interaction with contractors and their resulting analysis. These experiences will facilitate the development of guidelines for tsunami hazard assessment, reflecting both the state-of-the-art approaches and limitations in the current methods employed by contractors. Specific objectives include: (1) Comprehensive documentation of model approaches used for tsunamis of various sources, including the basic physical approximations and resulting limitations, governing equations, and numerical modeling schemes; (2) Details of typical model usage, including bathymetric and topographic grid generation, model resolution, and turbulence closure schemes; (3) Discussion of practical issues when employing and analyzing model output; (4) Model applications specific for reactor hazard assessment, including methods of including high levels of conservatism, and how that conservatism should be systematically relaxed with realistic assumptions for given site; and (5) Delineation of the level of detail required by applicants when presenting model results in safety and environmental reports.

"Numerical Modeling in Support of Review of Various Nuclear Power Plant License Applications" Funded by the U.S. Nuclear Regulatory Commission through USGS, September 2008 to September 2012. PI: P. Lynett.

"NUREG/CR: Development of Guidelines for Tsunami Hazard Assessment of Nuclear Power Facilities" Funded by the Nuclear Regulatory Commission through Univ. of Washington, September 2011 to September 2013. co-PI: P. Lynett.

"Re-Analysis of Tsunami Hazard for Existing Nuclear Power Facilities" Funded by the Nuclear Regulatory Commission through Taylor Engineering, October 2013 to October 2018. PI: P. Lynett.