Numerical Simulation of Oil Spill from Crude Oil Tankers

Abstract

In this paper a numerical simulation method to predict the behaviour of spilled oil over the surface of the sea is proposed. On the basis of the shallow water assumption, dispersion of the oil slick is efficiently solved by a finite difference method. The simulation method is verified by comparison with experimental data obtained from scale model tests and tests at actual seas. The followings are main conclusions from this study: (1) From the discussions shown in the paper, the present method is effective to simulate the early stage of oil spill phenomena (i.e., gravity-inertial and gravity-viscous regimes). Especially, the accuracy of the numerical simulation is excellent in the gravity-inertial regime. In the gravity-viscous regime our numerical simulation slightly over estimates the area of spreading oil. However, this estimation is considered to be on the safe side. (2) The present method has the advantage of treating the arbitrary shaped boundary conditions such as ship hulls and oil fences and therefore it can be used to simulate actual tanker accidents. The method is also applicable to a wide range of related studies ; assessment of the performance of oil skimming vessels, investigation into the set-up strategy of oil fences around wrecked tankers, etc.