Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering Conference
Shanghai, China, June 5–10, 2022
Copyright © 2022 by the International Society of Offshore and Polar Engineers (ISOPE)
ISBN 978-1-880653-81-4; ISSN 1098-6189

www.isope.org

Study on coupling behavior between leakage of damaged tanker and ship motion
Zhiwei Ma, Jinshu Lu*, Wenfeng Wu, Junjie Sun, Bo Chen, Xuxiu Wang
School of Naval Architecture and Maritime, Zhejiang Ocean University.
Zhoushan, Zhejiang, China

ABSTRACT

between oil leakage and hull motion. In addition, there are too manyassumptions. For instance, the simulated external environment is tooidealized, such as only considering hydrostatic conditions, ignores theimpact of ship sloshing caused by offshore wind and waves on the oilleakage process. The model is excessively simplified, such as thedamaged oil tanker is simplified to the damaged oil tank and the ship
motion is simplified only considering a certain degree of freedom. So,
it can ‵ t meet the requirements of oil leakage prediction accuracy ofdamaged tankers.

In this paper, the coupling process between oil leakage and hull
motion of a stationary double hulled damaged tanker in still water issimulated. The coupling process is realized by constructing a threedimensional full-scale numerical model of the damaged tanker, using
overlapping grid technology and DFBI six degree of freedom solver.
The oil-water flow law is explored by analyzing the characteristic
parameters such as hull draft, inclination, oil leakage speed and oilleakage time. The influence of hull motion on oil leakage of damaged
tankers and its mechanism are obtained. The research shows that thedriving force of oil leakage is gravity and pressure difference for thesix degree of freedom motion damaged tanker. The change of the total
mass of the ship caused by the damaged tanker mainly causes the hull
heave movement. In the process of floating and sinking, the hullchanges the pressure of the oil and sea water on the hole, affecting theleakage speed and spillage. The greater the heave movement
amplitude, the greater the pressure difference on both sides. The
stronger the leakage power, the greater the leakage.

Yamaguchi et al. (1993) took the middle section of a typical VLCC
cargo tank as the research object, used a 1/50 scale model to study thecargo transportation behavior of a double hull tanker after grounding
and collision. They also analyzed the tests of a double hull tanker
after grounding and collision. The oil flow under the conditions ofdouble bottom height, double side width, oil tank size, fracture degree,
fracture position, fracture axial offset, initial thickness of water layer
in double cabin, water draft and cargo location were measured. The
dynamic characteristics of water and cargo flow in double hull space
after break are studied. Ohtsubo et al. (1994) studied the failure
behavior of oil tanker structure during collision and grounding
through full-scale or large-scale tests, and found the failure
characteristics of oil tanker structure. Lee et al. (2006) studied theinteraction between ship motion and inner tank sloshing by using
time-domain simulation method. Mohammad et al. (2011) studied theoil flow of damaged ships with different tank designs in collision andgrounding accidents. Mohammad et al. (2012) conducted theoreticalanalysis and numerical simulation of oil leakage in damaged oil tanks
based on hydrostatic theory. But they did not consider the impact ofhull motion on oil leakage. Yang et al. (2017) conducted acomparative study on the role of turbulence model andcompressibility in DHT oil spill. A criterion for selecting anappropriate turbulence model based on the computational robustnessof effective Reynolds number is proposed. The compressibility of
fluid is quite large on a small space-time scale, but it has little effecton the macroscopical oil spill process. Kollo et al. (2017) developed a
new modeling method. In the hydraulic simulation, it is found that

KEY WORDS: Oil leakage; Overlapping grid; 6-DOF motion;
Leakage characteristics
INTRODUCTION
With the development of marine transportation industry, there are not
only a large number of ships, but also tend to be large-scale. To someextent, it increases the chance of accidents. Although the navigation
technology is constantly improving there are still many cases of shipdamage accidents under many uncontrollable factors (collision,grounding, etc.). As long as the ships are in operation, they will
inevitably be damaged and caused huge losses, especially for oiltankers. A large amount of oil will leak into the sea, which not only
causes marine environmental pollution and economic losses, but also
threatens the safety of personnel on board. At present, the research on
the underwater oil leakage of double hull oil tanker is mainly based on
the hydrostatics theory, without considering the coupling effect961