Wind-tunnel pressure measurements on model-scale rigid downwind sails
Language
en
Article de revue
This item was published in
Ocean Engineering. 2014, vol. 90, p. 84-92
Elsevier
English Abstract
This paper describes an experiment that was carried out in the Twisted Flow Wind Tunnel at The University of Auckland to measure a detailed set of pressure distributions on a rigid 1/15th scale model of a modern asymmetric ...Read more >
This paper describes an experiment that was carried out in the Twisted Flow Wind Tunnel at The University of Auckland to measure a detailed set of pressure distributions on a rigid 1/15th scale model of a modern asymmetric spinnaker. It was observed that the pressures varied considerably up the height of the spinnaker. The fine resolution of pressure taps allowed the extent of leading edge separation bubble, pressure recovery region, and effect of sail curvature to be observed quite clearly. It was found that the shape of the pressure distributions could be understood in terms of conventional aerodynamic theory. The sail performed best at an apparent wind angle of about 55°, which is its design angle, and the effect of heel was more pronounced near the head than the foot. Analysis of pressure time histories allows the large scale vortex shedding to be detected in the separation region, with a Strouhal number in the range 0.1 - 0.3, based on local sail chord length.Read less <
English Keywords
Sails Aerodynamics
Downwind Sail
Pressure Measurements
Leading-edge Separation
Laminar Separation Bubble
Trailing-edge Separation
Origin
Hal imported