基于船机桨匹配和波浪统计的船舶失速系数分析

为减少温室气体排放，国际海事组织（IMO）提出了新船能效设计指数（EEDI）规范要求，但尚未明确其中失速系数的计算方法.针对失速系数的估算方法进行了分析探讨，提出了一种基于船机桨匹配和长期波浪统计数据的失速系数计算方法.该方法中考虑了船机桨间的能量传递和水动力相互干扰，同时用船舶运营海区的长期波浪统计数据作为环境参数，对一艘实际运营的集装箱船进行了试算，并与IMO规范值、中国船舶科学研究中心回归公式和目前应用较广的NMRI方法进行了对比.结果表明：由所提出的方法得到的失速系数，其变化规律与NMRI法一致且更为保守，能指导船舶能效设计，更有利于保障船舶在实海域中的航行性能.

Analysis of the Ship Speed Loss Coefficient Based on Hull-Engine-Propeller Matching and Wave Statistics

In order to reduce green-house-gas emission, international maritime organization (IMO) proposed the energy efficiency design index (EEDI) regulation, but has not specified the procedure for calculating the speed loss coefficient. Therefore, this paper aims at analyzing and proposing a calculation process based on hull engine propeller matching and long term wave statistics to estimate this speed loss coefficient. The proposed method takes into account the energy transmission among hull, engine and propeller as well as their hydrodynamic interactions; on addition, long term wave statistics of the ship’s operational regions are adopted as environment input, thus making the current method more objective and realistic. Calculation is performed to a containership in operation and the result is compared with IMO reference value, the regression formula of China ship scientific research center and the widely used NMRI approach. The result obtained by the current method shows the same trend as the NMRI method while being more conservative. Therefore, using the current method to guide ship energy efficiency design can better guarantee the navigation performance of the ship at actual seas. Key words：