Abstract
The biplane axial turbine with setting angle has been manufactured and tested to investigate the effects of setting angle, gap to chord ratio, and arrangement of biplane rotor on the turbine performance. The results have been compared with those of the biplane Wells turbine. A suitable choice of the design factors has been suggested. Next, the hysteretic characteristics has been clarified from the viewpoint of the design method. The hysteresis is more sensitive to the arrangement of biplane rotor and less sensitive to the setting angle and gap to chord ratio. By means of flow visualization, the relation between the overall characteristics and the behavior of wakes has been discussed.