根据船、机、桨关系,以船舶动力装置的能量传递为基础,基于MATLAB/Simulink仿真平台建立了主机能效模型。以某内河旅游船舶为研究对象,根据船体与主机参数,利用回归多项式法得到螺旋桨敞水特性曲线。在船舶上安装了油耗仪等传感器,采集了主机瞬时油耗、船舶对地航速、对水航速等数据,并计算了主机的实际能效。针对实船采集数据,分析了航道水流速度的分布特征。基于仿真模型,计算了船舶在不同航道水流速度与对水航速下的主机能效,比较分析了实测数据与仿真结果,并对模型进行了验证。验证结果表明:航道水流速度偏度为-0.033,总体服从正态分布;船舶实际主机能效与对水航速之间不是一一对应关系,而是相关系数为0.824的散点分布;船舶主机能效模型能够精确地表征船舶在航行过程中的主机能效水平及其变化规律,误差不大于10.5%。
According to the hull-engine-propeller relationship, the energy efficiency model of marine main engine was established based on the energy transfer within marine power plant and MATLAB/Simulink simulation platform. An inland river cruise ship was chosen as a research object, and the open-water characteristic curves of propeller were obtained by using the regression polynomial method according to the parameters of hull and main engine. Several sensors (such as fuel consumption instruments) were amounted on the target ship, the instantaneous fuel oil consumption of main engine, the marine speed relative to ground, and the marine speed relative to water were collected, and the real main engine energy efficiencies were calculated. The distribution characteristic of water speed was analyzed according to actual collected data. The energy efficiencies of main engine under different water speeds and marine speeds relative to water were calculated based on the simulation model. The actual data and simulation results were compared and analyzed, and the model was verified. Verification result indicates that water speeds are almost normal distribution with skewness of --0. 032, the one-to- one correspondence between real energy efficiency and marine speed relative to water is not observed, but their relationship is a scattered distribution with correlation coefficient of 0. 824. The established energy efficiency model can accurately evaluate the energy efficiency level and changing rule of main engine in navigation process, and the error is less than 10.5~. 3 tabs, 11 figs, 26 refs.