From drawing board to Oceanbird

1. EARLY SKETCH

The sketch above is from 2017, when the design started to fall into place. Early on, we started to work on achieving an aerodynamically efficient hull, in harmony with the wing rigs. Back then, there were only four of them, instead of today’s five. It was early conceptual design development.

2. TELESCOPIC WING RIGS

We redesigned the wing rig into a telescopic solution where you can adjust the height of the sails by pushing sections up and down, which has many advantages. The construction is more robust, it´s possible to quickly get rid of wind power in strong winds and in port, you are able to pass under bridges and it also saves space on deck. You don’t have to expose the whole sailing area if you just need a small amount of power. The telescopic solution is also more efficient from a sailing performance point of view.

Designing Oceanbird, we had to pay much more attention to the aerodynamics than we normally would do. Not only do the wings have more in common with airplane wings than traditional sails, they also interact with the hull in a very complex way. This means that we can actually harness the power of wind in a very efficient way, where the different parts of the hull and wings are working closely together, boosting the vessel performance.

3. UNDERSTANDING THE WIND

A key to developing wind-powered vessels is to understand how the wind behaves. There is little systematic measurement data to validate models of wind behavior in the atmospheric ground boundary layer (0–250 metres above water) over the open ocean. To understand the characteristics of the wind in this region, we conducted a series of experiments together with KTH, our partner together with SSPA in the project wPCC (wind Powered Car-Carrier). We installed laser measuring equipment on an ocean-going ship´s deck during the autumn of 2019. This allowed us to measure both wind speed and wind direction from the ship deck up to 300 metres above deck, where the wings will operate.

4. MODEL IN OPEN WATER

Students in the course Naval Design at KTH made a sevenmeter model of Oceanbird. In May 2020, the students drove the model to Viggbyholm Boat Club, north of Stockholm. There they performed an inclination test to get the center of gravity and also tested the motoring part and the rudders.

5. HULL DURABILITY AND WAVE TEST

During 2020, SSPA performed several tests of an Oceanbird model in their towing tank. Earlier, we had done a number of computer simulations and needed to confirm the results of the experiments. We were interested in the hydrodynamic performance, focusing on the hull, rudder and propeller. Once in the water, the model behaved very well. We saw a smooth wave pattern behind the model, which indicated that the resistance was low and the hull was efficient. A few months later, SSPA exposed the model to difficult waves to see if it would hold a steady course.

6. OCEANBIRD TRANSLATED TO ORCELLE WIND

In February 2021, Orcelle Wind was presented to the world. Ever since Wallenius Wilhelmsen announced that they will be the first to order a vessel of the Oceanbird concept, called Orcelle Wind, it have been busy days for our Naval Architects. In close dialogue with our customer, we are now adjusting the design for their requirements. Meanwhile, work continues to develop the concept of Oceanbird for other types of vessels.

This article is shared by courtesy of Wallenius Marine, which designs ships powered by wind. They use big data and high level IT security to be able to manage ships in the most efficient and safe way.