Experiment and numerical simulation of an aluminum circular-blade butterfly wind turbine oleh Yutaka HARA, Akira SHIOZAKI, Hiroaki NISHIONO, Shigenori SAITO, Keisuke SHIOYA, Takahiro SUMI, Yuhei MATSUBARA, Yoshiyuki YASUMOTO, Katsuhiro TAKAGAKI, Shohei KOGO