重新评价低速机主机轴带发电机(定距桨系统)的节能及经济性

在定距桨系统中的低速机主机轴带发电机与常规柴油发电机的燃油耗量比较时,必须在等航速下把采用轴带发电机时的主机额定输出和采用柴油发电机时的主机额定输出与船型、螺旋桨的设计转速,以及在主机额定输出区中所选的额定输出点联系起来作为整体考虑。作者提出主机轴带发电机与柴油发电机相比较的节能精确计算法。按此计算法,轴带发电机未必有节能效果。

RE-EVALUATION ON ENERGY-SAVING AND ECONOMY OF SHAFT GENERATOR DRIVEN BY SLOW SPEED MAIN ENGINE WITH FIXED PITCH PROPELLER

The paper deals with comparison between a S/G by M/E with F. P. P. and a conventional diesel generator in terms of fuel oil consumption, from which it is shown that the MCR of M/E with and without S/G, where a D/G is used, under a certain constant ship speed, must be considered together with hull form, design revolution of propeller and optimum MCR point selected in layout area.From above point of view, an accurate calculating method for energysaving of S/G in comparison with D/G is proposed.According to the accurate calculating method, M/E driven S/G does not necessarily have energy-saving merits as compared with D/G, and energy-saving effect of S/G driven by low speed M/E with E. P.P. therefore needs to be re-evaluated.