A 3-D Tanker Spill Visualization (TSV) Program

A basic problem in both tanker regulation and the public perception of tankers is that tanker oil spillage is not as simple as most people think. For the general populus including almost all regulators, you either have a hole in the ship or you don't. In fact, the amount of spillage is critically dependent on much more than simply the existence or non-existence of a hole. Much more important factors are location of the hole, especially the vertical extent, the internal and external pressure at the top of the damage, the size of the damaged tank(s), and the ability of the configuration to capture oil flowing out of hydrostatically overbalanced spaces in hydrostatically underbalanced spaces. (Another key factor is the ability of the structure to withstand the damaged stress pattern without further damage. But that will be addressed in a separate project.) The physics is simple -- little more than Archimedes Principle -- but the way these factors are related can be fairly complex and even for experienced tankermen surprisingly counter-intuitive.

Therefore an important part of this project will be to generate a 3-D visualization of tanker spillage. This will allow anybody to study a range of designs, loading patterns, and damage and actually watch what happens. Initially spillage rate will be based on a simple varient of the Torricelli equation. The development of a more accurate model of exchange flow spillage rate is an open research issue and will be addressed in the Spill Rate Project.

With such a tool, any intelligent laymen will be able to find out for himself what is important and what is not to spillage. He will quickly find that some ideas which at first glance promise big reductions in spillage make little or no difference -- someetimes even increasing spillage -- while ideas that at first glance sound hopelessly theoretically can generate massive reductions in spillage.

The single most important audience for this program will be the tanker crews themselves. The fact is that most tankship deck officers have at best a tenuous grasp of Archimedes Principle and its implications for spillage. Our expereince with MLOAD has shown that even a non-graphic spill calculator can be an important training tool, a graphic display of these results will be an order of magnitude better. In the longer run, one goal will be to distribute the output of this project with CTX_MATE, so that this visulization capability is installed on-board.

This project depends on the CTX_MATE project which will produce the ship's draft, trim and list, and the equilbrium tank ullages and oil/water interfaces for the given ship, loading pattern, and damage location(s).

The current intention is to use the Open Source VTK Package as our 3-D visualization toolkit.

Email about this project should be sent to tsv@c4tx.org.