FIELD: converting energy of flowing fluid to useful work. SUBSTANCE: device has vertical power take-off shaft provided with cylindrical sections of shaped blades separated with disk holders. The blades are arranged parallel to the shaft in two series over concentric circumferences. The blades are constructed as conjugated arcs of different radius, the arc of grater radius being closer to the shaft. The chords of the arcs are mutually perpendicular and inclined at 45 deg to the radius drawn from the shaft axis to the mostly spaced edge of the blade. EFFECT: simplified design. 3 dwg
