STUDIES OF THE RESISTANCE OF LNG CARRIERS TO COLLISIONS
摘要
LNG carriers must be designed to withstand collision impacts. Particularly in ports, the risk of an LNG spill must be minimized. This paper discusses studies of the resistance of LNG carriers to collisions. It deals with the evaluation of critical impact speeds of typical 125,000 cu m LNG tankers. The critical impact speed is the speed at which a ship may strike an LNG carrier without any damage to the cargo tanks. Critical speeds were determined for various sizes of striking ships and both for floating and moored LNG carriers. The calculations are based on the Minorsky method, which was, however, modified on the basis of recent collision test results. The effect of the angle of impact and the point of attack were studied. To compare actual collisions with theoretical critical speeds, collisions between a 125,000 cu m LNG carrier and a typical dry cargo ship as well as an oil tanker were simulated by a computer-aided ship-handling simulator. The results show that double-wall LNG tankers are safe in collisions.