Wing Cell Geometry and Pressure Distribution over The Surface of A Paraglider

Abstract

The paraglider poses an interesting challenge to the aerodynamics researcher. This paper studies aerodynamic issues involved in the deployment and operation of a paraglider. The surface shape of the paraglider is determined by the pressure distribution in and around the paraglider, the porosity of the fabric, and the presence of cell cross-flow, in addition to the fabric structure and the tensions in the lines at the attachment points. In this studies wind tunnel test of a three dimensional paraglider wing canopy cell model has been performed. Two dimensional (i.e. pressure measurement along the cord length and span wise direction) pressure distributions over the surface have been investigated at different angle of attack, simultaneously wing surface shape profiles has been measured directly. Surface contours of paraglider during operation in a wind tunnel are obtained. The pressure distribution in turn depends on the attitude and the surface shape. It has been observed that the minimum pressure over the surface of the wing increases towards the edges from the central section. Wing end effects also been investigated. There are a certain percentage of upper surfaces affected by the downwash

Keywords

• Paraglider, Aerodynamics, Flexible wing, Three dimensional measurements

References

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