A study on unsteady fluid-dynamic force characteristics of a pitching wing with leading edge protuberance

We conducted a study on unsteady characteristics of fluid-dynamic force acting pitching NACA0012 wing with linear leading edge (Baseline) and protuberance (Wave) in low Reynolds number region (Re =4.32×104) for the development fish-type autonomous underwater vehicle. To investigate effect motion force, measurement flow visualization were by using wind tunnel. In case Baseline, increase frequency amplitude produced higher lift than quasi-steady one upstroke phase. On other hand, downstroke phase, decreased become lower state. However, at large such as 15° where rapid decrease was observed end change close to one. Flow showed that phase caused separation control motion. Wave, although same forces Baseline observed, average smaller fluctuation which confirmed regardless conditions. Furthermore, 2-dimentional potential analysis revealed effects drag attributed considerably small compared separation.