Department of Naval Architecture and Marine Engineering, Faculty of Engineering, Alexandria University, Alexandria, 21544, Egypt.
Thermochemical Power Group (TPG), University of Genoa, Via Montallegro 1, 16145, Genoa, Italy.
Environ Sci Pollut Res Int. 2022 Dec;29(60):90509-90519. doi: 10.1007/s11356-022-22116-7. Epub 2022 Jul 23.
Environmental issues and targets to reduce greenhouse gas emissions have reinforced attempts to increase energy efficiency for all stakeholders, including the shipping industry. International maritime organization (IMO) has prescribed operational and design measures to develop energy efficiency and decrease ship emissions, and one of the effective operational measures is trim optimization, which is a feasible measure because it does not necessitate ship structural modification or engine advancement, but it can reduce the ship resistance and decrease fuel consumption. The study of trim optimization can be implemented by conducting experimental tests, but it is a difficult, expensive method and consumed more time. Therefore, the present paper proposes a numerical method to predict the optimum trim which achieves the minimum ship resistance and lower fuel consumption. The current paper investigated two types of ships as a case study, bulk carrier, and container ship. The optimization process has studied several trim conditions, ship drafts, and speeds. The results showed that positive trim (trim by bow) have an increasing effect on fuel consumption, while the negative trim (trim by stern) have a decreasing effect on fuel consumption. Fuel-saving based on using optimum trim at each speed is a significant quantity to be benefited as it would reduce the operating costs and increase the energy efficiency.
环境问题和减少温室气体排放的目标，加强了包括航运业在内的所有利益相关者提高能源效率的努力。国际海事组织（IMO）规定了运营和设计措施，以提高能源效率并减少船舶排放，其中一项有效的运营措施是吃水优化，这是一项可行的措施，因为它不需要船舶结构修改或发动机改进，但可以减少船舶阻力并降低燃料消耗。吃水优化的研究可以通过进行实验测试来实施，但这是一种困难且昂贵的方法，并且需要更多的时间。因此，本文提出了一种数值方法来预测最佳吃水，以实现最小的船舶阻力和更低的燃料消耗。本文研究了两种船舶作为案例研究，即散货船和集装箱船。优化过程研究了几种吃水条件、船舶吃水深度和速度。结果表明，正吃水（船头吃水）对燃料消耗有增加的影响，而负吃水（船尾吃水）对燃料消耗有减少的影响。在每个速度下使用最佳吃水来节省燃料是一个很大的数量，可以降低运营成本并提高能源效率。
