オイルフェンスの係留方式について

抄録

To prevent the spreading of oil spills, there are often used mechanical barriers consisting of floating chamber, skirt and sinker. Almost barriers of this type have pretty weighty stabilizing sinkers at the bottom of skirt unanimousely to prevent the inclination of skirt by water current. This shows nothing but that these barriers are moored at the top of skirt just under the floating chamber, when they are extended on sea surface.
However, it is questionable that the above mooring method is suitable for staying oil slicks.
This paper studies on the inclining angles caused by water current in the two mooring method as next; the one is that the barriers are moored at the top of skirt and the other is that they are moored at the bottom of skirt. And the facts which are confirmed or deduced both theorically and experimentally are as follows.
1) In case that such barriers as floating chamber-type are moored at the bottom of skirt vertically as possible, the inclinations of skirt are remarkably smaller than in case that they are moored at the top of skirt, although the floating chamber drifts in the rear side.
2) By mooring the bottom of skirt, oil staying capacity of barriers will be increased comparing to by mooring the top of skirt and moreover, the whole weight of barrier becomes far lighter because of needless of stabilizing sinkers.