Dutch Heesen Yachts has revealed new details about its largest construction project — 80,7-meter aluminum superyacht Project Cosmos (YN 19480). Although the ceremony of laying the keel to be held in may of this year, now work is in full swing.
Starting with the base — the development of naval architecture and hull design of the boat, the creators of the boats moved on to finding the nuances of design methods of computational fluid dynamics and directly physical model tests in reduced scale in the test pool, and finished with screws, and the steering system.
In all the above aspects of the project Heesen was based not only on the competence of its engineering Department, but also on the experience of regular partners — Van Oossanen Naval Architects and specialists in the propulsive plant of Rolls-Royce.
The first step was the creation of the concept of body type Fast Displacement (FDHF), which would ensure the yacht is not only high speed and efficiency, but also a particular hardness, and it is not easy, since “Space” — all aluminum. Note that at the request of the customer, the boat should reach maximum speed of about 30 knots.
to solve these problems, Heesen has developed a Backbone® — method design, which provides the necessary rigidity without adding mass, which could affect performance of the boat.
The solution was so successful that Heesen even patented this method.
To conduct physical tests at the shipyard specially built a scaled layout of the yacht with a length of 3.7 meters and ran it in a test pool science centre Wolfson Unit at Southampton University (UK). After you have collected the initial data for hydrodynamics, resistance and speed, the model has made self-propelled, radio — to study the impact of water pressure on the hull. The result provided valuable information to hone the design and further optimization of the Backbone.
In the case of such a big boat from “winged metal” it is particularly important to know the true forces acting on the body in the sea. And not only in order to comply with the requirements of Lloyd’s Register, but also to build a boat capable of withstanding the high loads.
The choice in favor of Fast Displacement and application of the technology Backbone on a yacht of this size cause a few raised the depth of the keel that really provides additional benefits. Because of the slightly increased precipitation “Space” boasts a very low coefficient of completeness of displacement. In turn, this means that part of the body, hidden under water, is very narrow. The result of all the boats stability at high speeds and relatively low fuel “appetite”.
The mission for the improvement of propellers with variable pitch fell on the shoulders of specialists Rolls-Royce. Promas — integration of the rudder and propeller into a single system to optimize hydrodynamic efficiency — their own know-how.
Thanks to the creation of a model of propulsion and steering complex Promas in scale 1:11 on-site Hydrodynamic Research Centre, Rolls-Royce (HRC) to Kristinehamn (Sweden) solved the problem of cavitation.
Cavitation is essentially the formation and subsequent collapse of bubbles in the fluid stream (in the case of boat — in which is incident on the propeller and behind the propeller stream of water), accompanied by noise and hydraulic shock.
Imagine how unpleasant it is, especially if the yacht is moving at full speed! The tests helped to identify the problem and solve it by changing the shape of the rudder.
“Project Cosmos again raises the bar not only for m but for the industry the construction of custom aluminum yachts in General. From a technical point of view, and from the performance point of view, we are entering a qualitatively new level. This 80,7-metre boat was designed not only to reach a maximum speed of almost 30 knots, but for walking on high — more than 20 knots — cruising speed in economy mode. The technical findings that we have introduced to meet all these requirements, once again stimulate the development of the world of superyachts,” says Arthur Brower (Arthur Brouwer), head of Heesen.
Over a 40-year history of Heesen earned the reputation of the shipyard, which is building the ultra-modern superyacht, expanding boundaries in design, speed and effectiveness: remember once the record Octopussy or a more recent Star Galactica, Galactica Super Nova and Home.