Abstract
A large number of studies of flow visualisations, developed on the upper surface of delta and of gothic wings, and of cones, have been carried out in the wind tunnel of the Valenciennes University’s Aerodynamics and Hydrodynamics Laboratory. These studies have provided a better understanding of the development and of the positioning of vortex structures and have enabled, in particular, the preferential nature of intervortex angles, thereby defined, to be determined. This study of the vortical structures developed on the upper surface of a double-delta wing has revealed that these vortex flows are quite complex and that vortex structures interact with one another. Indeed, it would seem that vortex behaviour has something of a universal nature. An angular conformity between primary and secondary vortex torques and the leading edges of the wing can be expressed by the law of filiation. Intervortex angles evolve with increasing incidence while fragmentation is a function of the apex angle. It would be interesting to recall that this particular spatial organisation of vortex structures, citing the concept of preferential angles, also appears in standard theories on aerodynamics as, for example, in those governing aerodynamic drag. Nevertheless, the link between interior and exterior vortex structures remains to be investigated further. Such studies might even prove the existence of a supplementary torque. In addition, the least resistance of secondary vortices in relation to their fragmentation inevitably calls for experiments to be undertaken with other possible combinations of slender bodies although these areas of research are beyond the scope of this article.
Highlights
Quite a considerable number of studies have been carried out to date into delta wings, ogival wings, cones and into more or less simple slender bodies formed from combinations of such components; the findings have dealt as much with the development of approximate theories as with the definition of models specifying vortex lift by unit area
A large number of photographic visualisations, concerning vortex flows developed on the upper surface of delta or ogival wings and cones, have been carried out at the Valenciennes University (France) laboratory [7] in such a way as to provide a better understanding of the development and positioning of vortex structures at low and mean incidence and at high incidence
Those vortex flows which are developed on such double-delta or delta-canard-wing-body configurations are quite complex : vortex flows can, be observed on the leading edges of the airfoil wing, but they appear on the leading edges of the canard-wing
Summary
Quite a considerable number of studies have been carried out to date into delta wings, ogival wings, cones and into more or less simple slender bodies formed from combinations of such components; the findings have dealt as much with the development of approximate theories as with the definition of models specifying vortex lift by unit area.Visualisations of hyper lifting vortex structures, mainly those carried out by Werle H [1,2,3,4,5,6], the analysis of pressure and speed fields created by these vortices, with or without breakdown – notably the analysis by Solignac et al [7] provide quite outstanding studies that are the standard works in their fields.Already described fully in such papers as, for example, those by [8,9,10,11] and Stahl [12], these findings offer today entirety a thorough knowledge of the properties of various types of slender bodies.given that the character of most of the aspects referred to remains empirical and limited to this or that degree of incidence [1,2,3,4] or to a numeric range [5], the way lies open, starting out from experimental data and various factors of analysis [6], for new attempts to be undertaken to examine the fundamental problems related to the position of vortices created by such slender bodies.A large number of photographic visualisations, concerning vortex flows developed on the upper surface of delta or ogival wings and cones, have been carried out at the Valenciennes University (France) laboratory [7] in such a way as to provide a better understanding of the development and positioning of vortex structures at low and mean incidence and at high incidence.These visualisations have enabled priority to be accorded to the study of examples of the most elementary shaped section, i.e., delta and ogival wings. A large number of photographic visualisations, concerning vortex flows developed on the upper surface of delta or ogival wings and cones, have been carried out at the Valenciennes University (France) laboratory [7] in such a way as to provide a better understanding of the development and positioning of vortex structures at low and mean incidence and at high incidence.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of Aeronautics & Aerospace Engineering
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
