Accession Number : ADA253656

Title :   Probabilistic Oil Outflow Analysis of Alternative Tanker Designs.

Descriptive Note : Final rept.

Corporate Author : HERBERT ENGINEERING CORP SAN FRANCISCO CA

Report Date : JUL 1992

Pagination or Media Count : 189

Abstract : The Oil Pollution Act 1990 mandates double hulls for all newly constructed tankers calling in U.S. waters. This study addresses the equivalence of four alternatives to the Double Hull design, based on projected oil outflow resulting from groundings and collisions. The four alternative designs were the Mid-Deck tanker, an underpressure system fitted to a MARPOL tanker, and two proprietary tankage configurations, the Coulombi Egg and POLMIS tankers. Three sizes of vessels, with cargo capacities of 50,000, 150,000, and 272,000 metric tons, were investigated. A probabilistic approach has been adopted for these analyses, utilizing statistical data for tanker casualities developed for the International Maritime Organization. Both side and bottom damage were considered. Loss calculations were based on hydrostatic balance principles. Initial oil loss at impact and dynamic losses due to current and waves were computed based on model tests. Plots illustrating the cumulative oil outflow for each damage condition are presented. Three 'figures of merit' were computed for each damage condition. These are: the probability of zero outflow, the mean outflow, and the extreme (1/10) outflow.

Descriptors :   *TANKER SHIPS, *OIL POLLUTION CONTAINMENT, *STATISTICAL DATA, SHIP HULLS, MARINE ENGINEERING.

Subject Categories : Marine Engineering
      Water Pollution and Control
      Statistics and Probability

Distribution Statement : APPROVED FOR PUBLIC RELEASE