Application of phase averaging method for measuring kites performance: onshore results

Morgan Behrel (1) , Kostia Roncin (1) , Jean-Baptiste Leroux (1) , Frédéric Montel (1) , Romain Hascoët (1) , Alain Nême (1) , Christian Jochum (1) , Yves Parlier (2)

1 IRDL - Institut de Recherche Dupuy de Lôme
2 Beyond the Sea

This paper describes an experimental setup aiming to control and measure performances of small leading edge inflatable tube kites, with surface area of less than 35 m². This setup can be deployed either onshore or on a dedicated boat. This article focuses on the onshore results. A 3D load cell is used to obtain the position of the kite under a straight-line assumption. A wind profiler (SODAR) is deployed to determine the wind speed and direction at the kite position. A specific post-processing of the data is presented, including phase averaging. The guideline of this work is to estimate the variation of the aerodynamic lift coefficient and lift to drag ratio along figure-of-eight trajectories. Results, for a chosen particular case, show a decrease of lift coefficient of about 20% of the maximum value during turning maneuvers of the kite. The lift to drag ratio evolution along a trajectory is also observed to go through a local minimum during turning maneuvers of the kite in this case. Influence of weight and inertia is highlighted introducing a point mass model of the kite and tethers. Buckling phenomena of the kite inflatable leading edge tube are highlighted and it is shown that they cause control problems.

Keywords: Kite; Phase averaging method; Kiteboat; Wind profiler

Domains: Fluid mechanics [physics.class-ph]

Morgan Behrel, Kostia Roncin, Jean-Baptiste Leroux, Frédéric Montel, Romain Hascoët, et al.. Application of phase averaging method for measuring kites performance: onshore results. Journal of Sailing Technology, 2018, pp.2018-05. ⟨hal-01889988⟩