Ki-Deok Ro
The Journal of Mechanical Science and Technology, vol. 23, no. 3, pp.836-844, 2009

Abstract : The performance improvement for a propulsion mechanism of Weis-Fogh type was attempted by using an elastic rubber wing. The elastic wings were made of rubber and wood with the rubber rate of 0%, 25%, and 50% in the wing area. The thrust and drag on the wing were measured for various velocity ratio V/U, opening angles of α=15° and α=30°. The average thrust coefficient and average thrust efficiency of the elastic wing were increased compared to those of the rigid wing, and the average drag coefficient was decreased; overall, by using elastic wing, the thrust, drag, and efficiency characteristics were improved. For an elastic wing with opening angle α=15° and rubber rate Rs=50% which relatively had the greatest performance improvement, thrust coefficient was increased by 30%, drag coefficient was decreased by 21%, and propulsive efficiency was increased by 17% in average compared to the rigid wing with Rs=0%.

Keyword : Hydraulic machine; Propulsion mechanism; Fluid force; Elastic wing; Rubber type; Performance improvement