Air Circulating Tank (ACT) is a system to drastically reduce the frictional resistance by air accumulated in the tank installed in a ships double bottom. The difference of the system from the air lubrication system using micro bubbles is no need of additional energy for injecting continuous air supply. The tank must be designed to make the air-escape minimum by generating a circulating flow of the air in the tank by the frictional force of the bottom water flow of the ship. In the present study, a very wide and shallow-draft ship is selected to get a large drag reduction effect by the ACT. In the present research project, the ACT is installed in the double bottom of the scale model of a 200m ship. CFD calculations are carried out to understand the characteristics of the generated air-circulation in the ACT and generated waves on the boundary between air and water. On the basis of the CFD results, an ACT has been developed, and model experiments to measure the resistance acting on the ship are carried out to know the effects. Finally, the scale effect of the ACT is investigated by using CFD.

Marine operations increase in the arctic, therefore collision risk of ships with ice bergs in the regions is higher and so the accurate assessment of the collision damage has become a necessity to estimate loads for the design of ship structures. This paper focuses on applications of ship–iceberg collision scenarios by using the KOSORI ice model which takes into account ice mechanic in terms of influencing parameters and, comparing results with rigid ice model. A case of collision of an iceberg with FLNG structure is studied by using the KOSORI ice model as well as the rigid body model for iceberg.

This study provides a comparison between aviation and maritime industries in the context of collision avoidance. Thus, it focuses on the regulations, operational practices, techniques and procedures in both aeroplanes and ships for collision avoidance. Due to safety and technology advancements in the aviation industry, advancements in aviation to prevent collision avoidance can be implemented in ships, developing a better situational awareness and improved navigational watch. Generally, the Officer of the Watch (OOW) on board ships is responsible for all the decisions that need to be taken on the navigational bridge. Consequently, this requires an immense amount of data analysis; moreover, this data is located in various locations on the bridge. Yet this can cause a work overload for the OOW, potentially leading to human errors and lack of situational awareness. This study reveals the shortages in maritime industry, helping us to adopt new safety-related enhancements and technologies to reduce the risk of collision at sea, which is inspired by the aviation industry.