We will co-host our regular seminar on this Friday, Nov 17, with the Coasts, Oceans, Ports & Rivers Institute (COPRI) student chapter. Dr. Navid Tahvildari of Old Dominion University will share a seminar about “Nonlinear Dynamics of Surface Waves in Dissipative Environments.” An abstract and bio are included below. Please join us in Mann 304 from 12:50-1:40pm.

Abstract: Accurate estimation of wave energy in the nearshore is critical for predicting storm forces on coastal infrastructure and estimating sediment transport. While it is well known that surface waves can undergo significant dissipation in interaction with aquatic vegetation canopies or muddy seabed, these processes are often modeled after applying simplifications that can affect both the rate of dissipation and the characteristics of surface waves resulting in potential inaccuracies in wave forecasting. Here, we present results of two phase-resolving numerical models that were developed to improve our understanding of mud- and vegetation-induced surface wave dynamics. First, a frequency-domain model is developed to simulate wave interaction with viscoelastic muds. The results indicate that compared to a widely-used model for viscous mud, viscoelastic mud can cause stronger or weaker dissipation depending on wave frequency affecting both bulk measures and the shape of the spectrum. Furthermore, a time-domain model is developed to simulate the interactions between waves and flexible vegetation. The model applies no limitation on vegetation rigidity, hence is capable of simulating extreme stem deflections as observed in seagrasses. Model validation and variations in frequency-dependent vegetative drag force will be discussed.

Bio: Dr. Navid Tahvildari is an assistant professor in the Department of Civil and Environmental Engineering at Old Dominion University. Dr. Tahvildari received his Ph.D. in civil engineering with coastal and ocean engineering focus from Texas A&M University in 2011. Prior to joining ODU, he was a postdoctoral scholar at the Environmental Fluid Mechanics Laboratory at Stanford University. His research interests include analytical and computational modeling of oceanic surface and internal waves, wave processes in natural and nature-based features, and the vulnerability of coastal infrastructure to flooding.