This paper presents a comparative analysis between single and twin-screw propulsion systems of a bulk carrier to evaluate the ship and propeller performance in terms of fuel consumption as well as to discuss the cavit...This paper presents a comparative analysis between single and twin-screw propulsion systems of a bulk carrier to evaluate the ship and propeller performance in terms of fuel consumption as well as to discuss the cavitation and noise criteria.An optimization model is developed to select the optimum propeller geometry and operational point along the engine load diagram for the selected engines of each case.The engines are selected from the same series due to the same behaviour along the engine load diagram.The propellers are selected from the B-series as fixed-pitch propellers.It has been concluded that while the components of the single-screw propulsion system are larger than the twin-screw,the single-screw propulsion system shows a reduction in fuel consumption than the twin screw by around 19%,thus affecting the amount of exhaust emissions from the ship.This model helps the ship designers to select a suitable propeller to improve the energy efficiency of the ships.展开更多
This paper presents a review of the different International Maritime Organization(IMO)initiatives to improve the ship energy efficiency of new and existing ships,which is considered one of the essential tasks to reduc...This paper presents a review of the different International Maritime Organization(IMO)initiatives to improve the ship energy efficiency of new and existing ships,which is considered one of the essential tasks to reduce Greenhouse Gas(GHG)in the maritime industry.First,the IMO effort and initiatives and the different indices suggested by the IMO are presented till the last version of the Marine Environment Protection Committee(MEPC),showing the effect of different technologies on reducing the level of indices and the suggested improvement of the terms of indices in the next years.Second,the short-and long-term strategies suggested by the IMO are presented,showing that the effect of indices will be noticed in the short term,while the new fuels will show a significant improvement in the long term.Finally,several examples of cooperation between the different organizations are presented,showing that transferring knowledge and experience will significantly impact the maritime industry and thus lead to the concept of green ships in the near future.This paper shows that the combination of different solutions,the cooperation between stakeholders and the sharing of the data and information are important to achieve the required goal.展开更多
文摘This paper presents a comparative analysis between single and twin-screw propulsion systems of a bulk carrier to evaluate the ship and propeller performance in terms of fuel consumption as well as to discuss the cavitation and noise criteria.An optimization model is developed to select the optimum propeller geometry and operational point along the engine load diagram for the selected engines of each case.The engines are selected from the same series due to the same behaviour along the engine load diagram.The propellers are selected from the B-series as fixed-pitch propellers.It has been concluded that while the components of the single-screw propulsion system are larger than the twin-screw,the single-screw propulsion system shows a reduction in fuel consumption than the twin screw by around 19%,thus affecting the amount of exhaust emissions from the ship.This model helps the ship designers to select a suitable propeller to improve the energy efficiency of the ships.
基金financed by the Portuguese Foundation for Science and Technology(Fundação para a Ciência e Tecnologia-FCT)(Grant No.UIDB/UIDP/00134/2020)which contributes to the Strategic Research Plan of the Centre for Marine Technology and Ocean Engineering(CENTEC).
文摘This paper presents a review of the different International Maritime Organization(IMO)initiatives to improve the ship energy efficiency of new and existing ships,which is considered one of the essential tasks to reduce Greenhouse Gas(GHG)in the maritime industry.First,the IMO effort and initiatives and the different indices suggested by the IMO are presented till the last version of the Marine Environment Protection Committee(MEPC),showing the effect of different technologies on reducing the level of indices and the suggested improvement of the terms of indices in the next years.Second,the short-and long-term strategies suggested by the IMO are presented,showing that the effect of indices will be noticed in the short term,while the new fuels will show a significant improvement in the long term.Finally,several examples of cooperation between the different organizations are presented,showing that transferring knowledge and experience will significantly impact the maritime industry and thus lead to the concept of green ships in the near future.This paper shows that the combination of different solutions,the cooperation between stakeholders and the sharing of the data and information are important to achieve the required goal.
