CFD streamlines blog

The EcoClipper ship concept has been created by a group of visionaries to help reduce global emissions and to create a greener shipping industry.
Concentrating on the traditional principles of harnessing the power of wind for ship propulsion, the EcoClipper ship will offer emission-free sustainable transportation for cargo, passengers and trainees around the world’s oceans. The new wind-powered fleet of ships will sail on four shipping lines with fixed schedules, thereby creating a new shipping logistics system for sail cargo vessels.

Specifically, the newbuild will be built in steel with modern construction techniques, based on the design of the Dutch clipper Noach, launched in 1857. Whilst the original ship was stated as the fastest Dutch sailing vessel ever built, Jorne Langelaan, EcoClipper’s CEO, wanted to test different hull shapes, to ensure the best performance for the sail cargo ship.

“The historic records of Fop Smit’s Noach are extensive. As the design of the ship was built around cargo carrying capabilities and passenger comfort. With Cape Horn Engineering’s expertise, we are able to fine-tune the ship to make sure it can sail as fast as possible, whilst retaining these necessities,” he said.
Computational fluid dynamics (CFD) technology is a crucial support for naval architects to optimise designs for critical elements such as weight saving, performance predictions, reducing emissions and ship optimisation.

Cape Horn Engineering is to provide the design team with expert CFD analysis for the design of the first hull shape.

“We are delighted to be involved in this innovative project. We are dedicated to reducing shipping emissions and improving air pollution, and we have a strong desire to contribute to such developments, to help protect our planet. Our investment in researching new technologies is a strong commitment, as we firmly believe the future needs to rely on sustainable energy sources,” Rodrigo Azcueta, CEO of Cape Horn Engineering, commented.

An ”ambitious” R&D programme was agreed and extensive CFD simulations for four different candidate hulls were performed and compared at different sailing conditions to aid the design process. One of the main challenges was to compare fairly dissimilar hull shape candidates without the aid of a velocity prediction program (VPP) where all hydro and aero forces are balanced.

With such a sail plan, consisting of three square rigged masts, maximum of 29 sails (including stunsails) and the maximum sail area being around 1580 square metres, the generation of a full aerodynamic model was out of the scope of the project. Therefore, sail coefficients for similar sailing vessels found in literature had to be used, to give a relationship between the driving force, side force and heeling moment, to enable accurate calculations to be made for the hydrodynamic performance of the hull candidates.

Another detailed investigation was aimed at finding the best possible position to install the hydro-generators that will provide the electricity requirements of the vessel. Velocity maps around the hull were analysed in order to find the locations with the most homogeneous and higher speeds for best performance of the turbines.

Source:ecoclipper.org