A Study to Improve the Performance of a Fixd Type Fin Stabilizer with Coanda Effect

Seo, Dae-Won; Lee, Se-Jin; Lee, Seung-Hee

Journal of Navigation and Port Research 2013;37(3):257-262.
Published online June 30, 2013.

콴다효과를 적용한 고정식 핀 안정기의 성능개선에 관한 연구

서대원, 이세진, 이승희

A Study to Improve the Performance of a Fixd Type Fin Stabilizer with Coanda Effect

Dae-Won Seo, Se-Jin Lee, Seung-Hee Lee

Abstract

A ship operating in rough sea may suffer from an undesirable motion which may severely degrade the performance of equipment onboard and give a person an uncomfortable feeling. Hence, roll stabilization received a considerable attention and various devices including bilge keels, stabilizing fins, gyroscopic, anti-rolling tanks, rudders and flaps have been conceived and utilized for the purpose. The Coanda effect is evident when a jet stream is applied tangential to a curved surface of a hydrofoil since then the jet increases the circulation around the foil and consequently the lift. Model tests and numerical simulation have been conducted to examine the practicality of a fixed type fin stabilizer augmented by the Coanda jet. The results show that the lift coefficient of the modified Coanda fin at the zero angle of attack identically coincides with that of the original fin at α = 26° when Coanda jet is supplied at the rate of C_j = 0.25. It is also shown that fixed type fin stabilizers for active control of the motions of ships and the other mobile units without rotation can be put to practical use if the Coanda effect is applied.

Key Words: Stabilizer fin;Fixed type fin stabilizer;Active control;Coanda effect;Jet momentum;NACA 0015