Recovery of oil‐pollutant from shipwrecks: DIFIS project

Abstract

PurposeThe purpose of this paper is to describe a method for the prompt intervention and remediation of tanker wrecks, for recovering the fuel trapped in their tanks.Design/methodology/approachThe environmental conditions, the functional specifications, the conceptual and preliminary design, the computational methods (fluid/structure interaction, computational fluid dynamics analysis and finite element analysis), the hydrodynamic scale model tests and the dynamic response analysis are included in this research paper.FindingsThe paper provides analytical and numerical tools for the response of subsea structures. These tools were calibrated by hydrodynamic scale model tests and extrapolated for different depths (shallow, deep water and ultra deep water).Research limitations/implicationsThe method is applicable as long as the trapped pollutant does not dissolve and is of lower density than the sea water.Originality/valueThis paper presents a new structure for the oil recovery from shipwrecks, which is simple and quickly deployed.

2 – Way Fluid – Structure Interaction Study for the DIFIS System’s Riser Tube

“…THE DIFIS SYSTEM DIFIS System was developed and funded during EU FP6 Framework for the oil recovery from shipwrecks [3], [4], [11]. DIFIS System is a flexible and quickdeployed structure around the shipwreck, which is able to remain in place until the pollution threat is eliminated.…”

“…The Riser Tube is vulnerable to the sea currents, due to mechanical and physical properties of polyethylene. For this reason, the design of the DIFIS's Riser Tube has based on the high natural frequencies of the structure, in order to prevent resonance [4].…”

“…The specifications and the models assumptions are based on simulation time minimization and peak residual errors prevention (Table 6). The fluid domain has been generated in CATIA (Figure 14a,b) following the proposed dimensions [4]. The mesh parameters are presented in Table 7.…”

“…The main difference between the DIFIS risers and offshore risers is the geometry, such as large external diameter that is presented in DIFIS System (2000 mm in DIFIS while the offshore are close to 800 mm). An extensive study for design, analysis and optimization of DIFIS System is presented by [4]. For a part of the riser tube, a modal analysis and a 1way FSI analysis were performed.…”

“…The results of the study show that the 15 meter polyethylene riser could avoid the vortex shedding and the riser responds as static. Moreover, the results of the study [4] has been validated and compared with experimental measurements from MARIN's hydrochannel [5].…”