A Data Replenishment Method for Self Regulating Sail-Assisted Ships Considering Big Data
The concept of intelligent sail-assisted ships based on big data comes to people's mind gradually. Data loss and distortion cannot be avoided during data collecting and preprocessing process. In this paper, a data replenishment method based on computational fluid dynamics (CFD) method is proposed and simulation cases are done to explain the method
Fundamental research for development of an advanced sail-assisted ship
A new hybrid sail that consists of a slat, a hard sail and a soft sail is designed for advanced sail-assisted bulk carriers. The new hybrid sail is assumed to utilize deck crane as its boom for practical application. Wind tunnel test for measuring aerodynamic characteristics has clarified that the hybrid sail has maximum thrust coefficient, 2.46. Interaction effect among plural hybrid sails and between hull and sails is also investigated experimentally. Although interaction effect that deteriorates sail performance is observed it is clarified experimentally that graduated arrangement of sails angle is effective for minimizing the undesirable interaction effect. Weather routing system for advanced sail-assisted ships is developed. The system searches for minimum fuel consumption route using a nonlinear programming method in which arrival time is constrained. Weather routing calculation using actual wind, waves and ocean current data in North Pacific Ocean has indicated that the advanced sail-assisted bulk carrier being equipped with the newly developed hybrid sails and utilizing the newly developed weather routing system can cut emission of carbon dioxide or fuel consumption by 17.4 percent totally compared to a conventional bulk carrier on Great Circle route.
On Aerodynamic Characteristics of a Hybrid-Sail with Square Soft Sail
It is a matter of concern on environmental problems all over the world to reduce exhaust of carbon dioxide gas (CO2) assumed to be one of causes of global warming. We consider that it is one of the important points to decrease the ship’s exhaust as the contribution of reduction of CO2. Some sail-equipped motor ships were constructed in Japan from the viewpoint of reduction on fuel consumption of a ship when the fuel price soared about 20 years ago (Ishihara, 1980; Matsumoto, 1982). In this time, the development of the high performance sail-equipped motor ship that uses clean energy as thrust of the ship is expected to reduce exhaust of CO2 in environmental problems. In our research institute, the investigation of aerodynamic characteristics on a hybrid-sail consisted of the rigid wing sail, which plays the role of a mast, a slat and a square soft sail was carried out at the wind tunnel in order to know performances and advantages of a sail-equipped motor ship. As a result the hybrid-sail presented in this paper is very useful compared with the previous sails and equipped on the deck of a motor ship actually. The performance of aerodynamic characteristics is also confirmed by calculation results of CFD.