基于营运效益的油船最优航速决策

Optimal speed decision of oil tankers based on operation benefit

针对油船营运效益,考虑主机燃油成本、锅炉燃油成本、辅机额外燃油成本和港口使费等变动成本和固定成本,建立油船航次净收益和每日净收益模型。应用基于可行域的遗传算法,通过实例分析验证模型的有效性。算例分析表明:考虑油船极限降速的航次净收益和每日净收益与航速之间的关系图为分层状曲面,分层点为临界航速;航速优化后的航次净收益和每日净收益比优化前分别提高0.21%和28.6%;以航次净收益最大为优化目标取得的经济效益略大于以每日净收益最大为优化目标取得的经济效益,但是前者的航次时间大于后者。建议油船优化目标的选择可根据航次租船合同对船期的要求和揽货市场的货源情况进行综合考虑。

In view of the operation benefit of oil tankers,variable costs(including main engine fuel cost,boiler fuel cost,additional cost of auxiliary machinery,and port charges)and fixed costs are considered comprehensively,and the models of voyage net income and daily net income are established.A genetic algorithm based on the feasible region is used,and the validity of the model is verified by example analysis.The results show that:under the consideration of the ultimate speed reduction of oil tankers,the relationship between the voyage net income(or the daily net income)and the ship speed is shown as a layered surface,and the delamination point is the critical speed;the voyage net income and the daily net income after the speed optimization are 0.21%and 28.6%higher than those before the speed optimization,respectively;the economic benefits obtained with the maximum voyage net income as the optimization goal are slightly greater than that with the maximum daily net income as the optimization goal,but the voyage time of the former is greater than that of the latter.It is suggested that the selection of the optimization goal of oil tankers can be considered comprehensively according to the requirements of the voyage charter contract on the shipping time and the market supply conditions.