Aeolian systems – Wind turbine and fresh water production on a sea barge; Pylon – wind blade interaction

Site last update April 29th_2021

Keywords: Aeolian wind turbine energy concentrator fresh water production sea barge pylon wind blade thermo energies

There are many wind systems for capturing wind energy. The most widespread system in the world is composed of a very tall pylon supporting at its upper end a three-bladed rotor oriented in the wind direction. Although in constant deployment and development (concerning the blade diameter and the materials) this system presents several disadvantages: very important foundations for keeping the pylon in place, low energy production per unit of mass, heavy infrastructure (control room, elevator), the motorized positioning of the rotor, considerable efforts on the blades, a low average efficiency and a short operating time under ground conditions.

Section 1_Wind turbine system on barge 

It describes a multi-stage wind system, mounted on a barge and fitted upstream with an energy concentrator. This system is naturally oriented towards the wind, provides a high average efficiency and a long operating time given its installation on the sea at a relatively large distance from the coast. The production of energy can materialize in several ways, more particularly, the production of electricity with a cable connecting the barge to the ground or to another barge and also the production of hydrogen and oxygen.

Section 2_Fresh water Production on Barge 

It describes a wind system similar to the previous one. It is also a multi-stage system, mounted on a barge and fitted upstream with an energy concentrator. This system is designed for the production of cold and, more particularly, for the production of fresh water. The system naturally turns towards the wind. Water production is dependent on atmospheric conditions, in particular, wind speed, temperature and the hydrometric degree of the air. These elements determine the most suitable places on the oceans for optimal water production: an area close to a tropical area where the wind is of relatively high intensity and with a sufficiently high humidity.

Section 3_Thermo Energies 

It describes systems that can be combined with the wind system for increased water production. These systems use the following techniques: thermo electricity, thermo acoustics or thermo magnetism each allowing a complementary production of cold which can be useful when the hydrometric degree is not sufficiently high or the intensity of the wind not sufficiently important.

Section 4_Urban Wind System 

It describes a wind system that can be adopted in an urban environment. This system includes a set of wind units installed inside a well formed by a round building or a set of buildings surrounding this well. The wind turbine rotors, unlike conventional wind turbines, are mounted parallel to the ground, the wind being directed in an upward movement. These urban wind systems can be used in open areas exposed to significant air circulation. The energy produced can be used for local electrical energy production with partial storage or redistributed to the local network.

Section 5_ Pylon – Wind Blade Interaction

It describes a system to attenuate the dynamic excitations resulting from the passage of a blade in front of the pylon supporting the rotor of a wind turbine. In the current situation, the large diameter pylon obstructs the wind, causing at least two problems. Firstly, when a blade passes in front of the pylon, the force exerted by the air on the blade is reduced because the air cannot flow directly downstream of the blade. Secondly, the pylon with a large cross section generates strong turbulence downstream of the pylon which is doubly excited when a blade passes in front of the pylon. Furthermore, the emergence of strong turbulence downstream of the pylon tends to increase the apparent diameter of the pylon (hydraulic diameter) representing the lateral section where the air cannot flow naturally. One solution to reduce all of these excitations would consist in installing a profiled mobile body around the pylon. Due to its profile and its mounting on the pylon, the mobile body is automatically oriented facing the wind. The thickness of the mobile body being small because subjected to little mechanical stress and the turbulence induced on the pylon being reduced, the hydraulic diameter of the pylon is reduced thereby generating less stress at the blades.

More information will be provided during 2021. For more information on this theme, please contact the author.