Design, operation and analysis of wind-assisted cargo ships

Concept Design and Performance Evaluation of a Fossil-Free Operated Cargo Ship with Unlimited Range

“…The numerical model used was developed to simulate the performance of a fossil-free operated cargo ship in realistic weather conditions. The presented methodology integrated real route conditions with the ship performance model ShipCLEAN [15,17], which simulated the ship performance using Flettner rotors together with renewable electric generators and an energy storage system to estimate the available energy. This integration made it possible to evaluate ship journey times, energy consumption, and energy production for different routes, ship types, sailing conditions, and renewable energy system configurations.…”

“…Flettner rotors have been selected in the study as the main propulsion system for their high efficiency in real environmental conditions, their flexibility and simplicity in operation, and their small sail area that reduces their interference with other renewable technologies on deck. Additionally, the ShipCLEAN model has already been validated proving reliable results using Flettner rotors as a wind-assisted propulsion system [15].…”

“…Additionally, a parameter defining the maximum allowed power consumption of the rotors is introduced. In this case, the conditions were re-optimized; see [15,17] for details. In the current study, ShipCLEAN was used to predict ship speed and Flettner rotor power consumption, respecting 4 DOF.…”

“…The rotors are installed in the front of the ship to advance the center of forces. An advanced position of the rotors, and the high side forces of the Flettner systems, are proved to give the most adequate drift condition for the studied ship to maximize the range of wind angles that the ship is able to sail and to minimize the required rudder angle for each sailing condition [15]. The previous studies [14,15] demonstrated that the configuration established with the respective rotor dimension is the most beneficial, assuming the attained speeds and energetical efficiency as the most critical aspects.…”

“…Additionally, the current study aims to demonstrate the applicability of the ship performance model ShipCLEAN [15] to define and simulate the propulsion system of the fossil-free concept ship with wind technologies as the main propulsor. From the ship dimensions, the wind propulsion system characteristics and weather conditions, ShipCLEAN evaluated the equilibrium of forces and moments in 4 degrees of freedom (surge, sway, yaw, and heel) and predicted the obtained ship speed and energy demand for the rotors for pure sailing (see Section 2.1).…”