This article presents the influence on the stability of a container ship, by connecting a Flettner balloon, as wind energy capturing system. Flettner balloon is a generator of electric power, filled with helium that rotates around a horizontal axis and sends the electricity using a cable. It rotates around a horizontal axis in response to the wind, effectively generating clean, renewable electricity at a lower cost than all competing systems. These article major points determined by the authors are: calculation of the forces which influence the balloon, calculation the influence of the balloon on the ship transverse and longitudinal stability, calculation of the ship new displacement, new draft, new GM and period of rolling. As a conclusion of the article, the reader will discover that the transverse stability of the ship will insignificant decreased with a small value of 0.01 and the longitudinal stability will be improved by 0.7532. The article demonstrates that a Flettner balloon, installed on a container ship, is a possible concept of capturing wind energy.

The time allotted to a single ship at berth varies greatly depending on the characteristics of the ship, the volume of cargo and its specifications.. Taking into account the service time and the problem of terminals by overcrowding of waiting ships and available berths (which may vary in number, depending on the size of ships already berthed), the average waiting time is calculated and obtained. The operating process is usually sequential, ie each type of cargo is stacked separately from the other types. For this reason, the operating time was considered to consist of four other indicators, which correspond to the main types of cargo of Ro-Ro / Ro-Pax ships: complete trucks, semi-trailers, • passenger cars, vehicles as goods themselves. Also, the time of operation of the goods by the dockers can be formulated by two other different terms: the time related to the ship and the time in the terminal. In this context, we intend to analyze the capacity of the terminal in Constanța Port.. Two different scenarios are considered: a more "common" case for the studied terminal with 40 semi-trailers and 80 trucks to be unloaded and the same amount to be loaded and an "extreme" case in which all goods are composed of semi-trailers ( 160 plus 160 in total). By using simulation models, the values for the optimal quay time were obtained, in relation to the number of units for loading data in the specified scenarios. Using modeling algorithms, we obtain reports of situations that include tables and graphs that allow the optimization of terminal operation.

The aerodynamic forces acting on a kite proposed for propelling marine shipping are investigated using computational and experimental means. Attention is given to the kite's positions as perpendicular or nearly perpendicular to the air flow that still possess potential for thrust generation but cannot be analysed using finite wing models applicable for kites at low angles of attack. Good agreement is achieved in the prediction of the time-averaged drag coefficient between the large eddy simulations (LESs) of a full scale kite and wind tunnel measurements of a small scale kite model. At zero-yaw conditions both the time-averaged drag and lift (side) forces show behavior similar to the literature-reported empirical relations for flat plates of the same aspect ratio (AR), but with differences of up to 20% in the coefficients’ values. Thus, the plate’s known empirical formulae for aerodynamic forces at zero yaw angles may be used as fast low-accuracy prediction tools before engaging with the more costly turbulent flow computations and wind tunnel tests. Yawing moderately the kite can actually increase mildly the drag but further yawing or pitching it reduces the dominant drag force. Both the drag and lift show unsteady components that are related to the large turbulent wake behind the kite and vortical shedding from the kite's ends. Power spectra of the aerodynamic forces’ coefficients are presented and analysed.

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