The purpose of this study is to investigate the effects of three external forces (tidal current, wind, and waves) on the movement of oil spilled during the Hebei Spirit oil spill accident. The diffusion of the spilled oil was simulated by using a random walk (RW) model that tracks the movement caused by advection-diffusion assuming oil as particles. For oil simulation, the wind drift current generated by wind and tidal current fields were computed by using the environmental fluid dynamics code (EFDC) model. Next, the wave fields were simulated by using the simulating waves nearshore (SWAN) model, and the Stokes drift current fields were calculated by applying the equation proposed by Stokes. The computed tidal currents, wind drift currents, and Stokes drift currents were applied as input data to the RW model. Then, oil diffusion distribution for each external force component was investigated and compared with that obtained from satellite images. When the wind drift currents and Stokes drift currents caused by waves were considered, the diffusion distribution of the spilled oil showed good agreement with that obtained from the observation.

Lee, K.H. and Kim, T.G., 2018. Three-dimensional Numerical Simulation of Airflow in Oscillating Water Column Device. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1346–1350. Coconut Creek (Florida), ISSN 0749-0208. An Oscillating Water Column (OWC) is a wave energy converting technology that uses the compressed and decompressed airflow induced by the vertical oscillations of water column inside the chamber as a driving force of an airflow turbine. In this study, three-dimensional numerical simulations of a bottom-fixed OWC are performed to understand the interaction of an OWC device with regular waves. The open-source CFD model REEF3D is used, which is able to consider immiscible two-phases (air and water) using the Reynolds-averaged Navier-Stokes equations. The simulation capability of REEF3D is validated by comparison with experimental data for wave deformations caused by the OWC and air-flow fields and the airflow velocity in the chamber. The numerical results revealed that the CFD numerical tool REEF3D can successfully simulate wave deformations caused by wave-OWC interactions, and directly estimate an air velocity inside the chamber. In addition, it was found that a phase difference occurs between time series of free surface evolution and air velocity evolution.