冰级船主机功率理论预报方法研究

强非线性冰载荷对极地航行商船的阻力和主机功率计算均提出巨大挑战。以往计算冰级船主机功率时,通常采用规范法的经验公式。尽管经验公式计算简便,但由于没有考虑航速变化对主机功率的影响,计算结果往往过于保守。本文基于离散元的理论方法和数值模型,采用阻力-速度曲线法建立了冰区加强型商船主机功率计算方法。借鉴中国商船“永盛轮”首航北极的实际航行经验,将预报方法应用于B1冰级的36000 t冰级多用途船的主机功率计算中。计算结果表明,该方法计算获得的主机功率较规范法小。该预报方法将为我国极地商船设计与制造提供技术支撑。

Theoretical calculation method of power of main engine of ice-classed ships

Nonlinear ice loads present huge challenges on calculating the resistance and power of main engine of iceclassed ships.Empirical formulas of the rules of classification society are usually adopted to calculate the power of main engine of ice-classed ships.Although it is easy to use the empirical formula,the result is usually much larger than that needed due to the neglect of the effects of speed.Based on the theoretical method and numerical model of Discrete Element Method(DEM),resistance-velocity curve is used to calculate the power of main engine of ice-classed ships.Considering the actual navigation experiences of Chinese merchant ship‘Yongsheng’through arctic route,the proposed method is applied to calculate the power of main engine of a B1 ice-classed 36000 DWT multi-purpose vessel(MPV).It is found that the calculated power of main engine of this method is smaller than that obtained from empirical formulas of the rules of classification society.The method and model aim to provide technical supports for the arctic navigation of Chinese merchant ships.