The physics of oil outflow from crude oil tankers during ship-ship collisions
Qu, Guan Lin
Date of Issue2016
School of Mechanical and Aerospace Engineering
The consequences caused by tanker collisions have become one of the main sources of oil pollution. Therefore this project is brought out to study on the physics of oil outflow from crude oil tankers during ship-ship collisions. The main aim of this paper is to find out the amount of oil outflow and factors that affected. Relevant researches have proven that hydrostatic balance plays a significant role in determining the amount of oil outflow. Due to the different densities of oil and seawater, different pressures will be generated at the same height. Hydrostatic balance can be only achieved when the internal oil pressure is equal to the external seawater pressure. Therefore the collision may cause an exchange flow of oil and seawater. The flow will stop when the ship approaches equilibrium. Based on that principle, an experiment is designed to find out the amount of oil outflow. PANAMAX, AFRAMAX, SUEZMAX and VLCC are the four tanker categories chosen for the study. Under these four categories, the effect of different vertical and longitudinal damaged locations as well as different ballast conditions on the amount of oil outflow will be obtained. By using the HECSALV software, simulations can be conducted and data can be obtained for further discussions. After tabulating and analyzing on the data obtained, the amount of oil outflow is found out and factors affecting the amount of oil outflow are determined. With a constant ship size and ballast condition, vertical damaged locations have a great impact on the percentage of oil outflow: the lower the damaged location, the smaller the amount of oil outflow. Besides that, longitudinal damaged locations have minor effect and it can be strengthened with a greater ballast condition. Ship sizes do not have significant effect on the percentage of oil outflow. However, VLCC seems to leak the largest amount due to its largest capacity.
Final Year Project (FYP)
Nanyang Technological University