• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.643-648
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• 2014

세일링 요트 (sailing yacht)는 세일 (sail)의 양력을 주로 이용하여 추진력을 얻는다. 요트 경주에서와 같이 항주 속도가 중요한 문제에서는 세일의 성능이 좋을수록 빠른 속도를 낼 수 있기 때문에 세일 주변의 유동해석을 통한 성능 추정과 효율의 최적화는 매우 중요하다. 본 논문에서는 일반적인 경주요트의 형태로써 지브 세일 (jib sail)과 메인 세일 (main sail) 그리고 한 개의 마스트(mast)로 구성된 슬루프(sloop)형 요트에 대한 유동해석을 하였다. 풍상범주 상태에서의 30ft급 세일링 요트인 KORDY-30의 jib sail과 main sail의 높이에 따른 단면을 모델링하였다. 슬루프형 요트의 경우, 세일링 요트에서 jib sail과 main sail이 각각 단독으로 있는 형태의 요트보다 세일의 개수가 증가함에 따라 양력이 증가하지만 항력도 따라서 증가 할 것이라고 가정했다. 따라서 jib sail의 각도를 다양하게 변화시켜 양력계수와, 항력계수의 변화를 살펴보고 그에 따른 양항비의 분석을 통해 최적의 효율을 갖는 jib sail의 각도를 알아보았다.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.4 s.148
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• pp.431-439
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• 2006

Due to the limitation of size of the test section, blockage effects could not be avoided in the model test of yacht sails for common wind tunnels. In this paper, a numerical analysis is performed to investigate the blockage effects on the lift and drag forces measured from wind tunnel experiments for a 30 feet sloop yacht sail. Complex airflows around the jib and main sails including three-dimensional flow separations are calculated for various close-hauled conditions. It is found that the blockage of a wind tunnel changes the flow separation and consequently the lift and drag forces of the sails, especially the main sail, reduce and increase, respectively, due to the blockage effects.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.06a
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• pp.832-839
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• 2005

It is important to understandflow characteristics and performances of sailsfor both sailors and designers who want to have efficient thrust of yacht. In this paper the viscous flows around sail-like rigid wings, which are similar to main and jib sails of a 30 feet sloop, are calculated using a CFD tool. Lift, drag and thrust forces are estimatedfor various conditions of gap distance between the two sails and the center of effort of the sail system is obtained. Wind tunnel experiments are also carried out to measure aerodynamic forces acting on the sail system and to validate the computation. It is found that the combination of two sails produces the lift force larger than the sum of that produced separately by each sail and the gap distance between the two sails is an important factor to determine total lift and thrust.