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.