Investigation of the effects of hydrofoil set-up on the performance of an international moth dinghy using a dynamic VPP


Findlay, M.W. and Turnock, S.R. (2008) Investigation of the effects of hydrofoil set-up on the performance of an international moth dinghy using a dynamic VPP. In, Innovation in High Performance Sailing Yachts, Lorient, France, 29 - 30 May 2008. London, UK, Royal Institution of Naval Architects, 43-56.

Download

[img] PDF
Download (558Kb)

Description/Abstract

The International Moth dinghy is a 3.355m long single handed, una-rigged monohull dinghy. The class rules allow the use of hydrofoil that in certain wind conditions can significantly reduce resistance. A new velocity prediction program (VPP) has been developed to evaluate the impact of hydrofoil design and set-up on the performance of a Moth dinghy by simulating racing on a windward - leeward course. The VPP generates polar diagrams indicating the speed of the craft in a range of true wind strengths and angles. Sail force and windage are modelled using aerofoil theory. The drag model includes hull skin friction and residuary resistance, profile and induced drag for every foil, wavemaking drag of the lifting foils and spray drag of the surface piercing foils. Using an iterative process the VPP determines the boat speed that balances resistive forces with drive force, heeling moment and righting moment and vertical lift forces with weight. A series of case studies demonstrate the use of the VPP by examining the effects of changing the span of the forward foil, adding end plates, and using different foil geometries on performance.

Item Type: Conference or Workshop Item (Paper)
Related URLs:
Keywords: sailing vpp, hydrofoil yacht
Subjects: V Naval Science > VM Naval architecture. Shipbuilding. Marine engineering
Q Science > QA Mathematics > QA76 Computer software
Divisions: University Structure - Pre August 2011 > School of Engineering Sciences > Fluid-Structure Interactions
ePrint ID: 52462
Date Deposited: 01 Jul 2008
Last Modified: 27 Mar 2014 18:35
Publisher: Royal Institution of Naval Architects
URI: http://eprints.soton.ac.uk/id/eprint/52462

Actions (login required)

View Item View Item