An experimental study of tip-vortex structures behind a small wind turbine with a flanged diffuser

K. Abe, H. Kihara, A. Sakurai, E. Wada and K. Sato; Dept. of Aeronautics and Astronautics, Kyushu University, JapanrnM. Nishida; Dept. of Aerospace Systems Engineering, Sojo University, JapanrnY. Ohya; Research Institute for Applied Mechanics, Kyushu University, Japan