A transition from ascending flight to vertical hovering: A study of a symmetric flapping modelM. Iima and T. Yanagita
Research Institute for Electronic Science, Hokkaido University Sapporo, 606-0812, Japan
received 22 November 2005; accepted in final form 31 January 2006
published online 17 February 2006
We study the motion of a model equipped with flapping wings under the influence of gravity (external force). This model moves in a two-dimensional fluid according to the hydrodynamic force generated by vortices separated from its wings. As a result of the interaction between the vortices and the wings, the model moves steadily in a direction against the gravity. Moreover, hovering, i.e., a steady flight staying in a particular position, can be achieved here by the effective use of vortex structures enhancing the hydrodynamic force that supports the model against gravity. The system exhibits a transition from the state with hovering to a state where hovering is impossible, as the model parameters are changed.
47.20.Ky - Nonlinearity, bifurcation, and symmetry breaking.
47.32.cb - Vortex interactions.
47.63.-b - Biological fluid dynamics.
© EDP Sciences 2006