RUNNER OF RADIAL-AN-AXIAL-FLOW HYDRAULIC TURBINE Russian patent published in 2000 - IPC

FIELD: mechanical engineering. SUBSTANCE: runner has anticavitational ribs on blades which protect the latter against cavitational destruction during operation when head deviates considerably from rated value. In runner containing hub, rim and blades coupled to them ribs are positioned on surfaces of blades. With their entry edges they adjoin entry edges of blades and are arranged between hub and boundary of development zone of blade cavitational erosion behind entry edges of blades near rim. In this case, ribs are mounted in directions of current lines in rated mode of operation. Extension of ribs along length makes up 0.05-0.2 of runner nominal diameter, and distance of entry edge of rib nearest to hub is 0.1-0.8 of length of blade entry edge projection of runner axle. Such arrangement of ribs makes if possible to reduce erosion destruction of blades by tens of times. EFFECT: enhanced efficiency. 3 dwg