Wind-tunnel pressure measurements on model-scale rigid downwind sails
Article dans une revue avec comité de lecture
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.
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Communication avec acteBOT, Patrick; VIOLA, Ignazio Maria; FLAY, Richard G.J.; BRETT, Jean-Sébastien (Ecole Navale, 2013)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 ...
Communication avec acteSOUPPEZ, Jean-Baptiste R.G.; BOT, Patrick; VIOLA, Ignazio Maria (RINA NZ, 2021-03)The spinnaker is the most powerful and one of the most used sails both in racing and cruising - yet its complex aerodynamics governed by flow separation is still not fully understood. While the flow around a spinnaker is ...
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Experimental Investigation of Asymmetric Spinnaker Aerodynamics Using Pressure and Sail Shape Measurements Article dans une revue avec comité de lectureMOTTA, Dario; FLAY, Richard G.J.; RICHARDS, P.J.; LE PELLEY, David; DEPARDAY, Julien; BOT, Patrick (Elsevier, 2014)An innovative method combining simultaneous on-water pressure and sail shape measurements for determining aerodynamic forces produced by sails is described and used on Stewart 34 and J80 Class yachts flying asymmetric ...
Article dans une revue avec comité de lectureVIOLA, Ignazio Maria; BOT, Patrick; RIOTTE, Matthieu (Wiley, 2013)A verification and validation procedure for yacht sail aerodynamics is presented. Guidelines and an example of application are provided. The grid uncertainty for the aerodynamic lift, drag and pressure distributions for ...