SPIRAL CASING FOR A HYDRAULIC TURBINE (OPTIONS)

摘要

FIELD: turbines or turbomachines.;SUBSTANCE: group of inventions relates to a spiral casing for a hydraulic turbine. Casing 32 comprises an array of spiral segments 37, 38 defining a passage to direct liquid entering the casing to a runner, inlet segment 36 defining a passage to receive liquid flowing into segments 37, 38, transition segment 34 connecting segment 36 segment 37 and defining a passage to direct liquid passing from segment 36 to segment 37, 38. Segment 36 extends at least partially around the runner and has an inner perimeter defining an opening to receive the runner. Cross-sectional areas of segments 37, 38 gradually decrease from inlet segment 37 of segments 37, 38 to a last one of segments 37, 38. Each of segments 37, 38 includes a gap aligned with the opening and the cross sections of segments 37, 38 do not correspond to a circular cross section. Segment 36 has a circular cross section. Segment 34 has a non-circular cross section, along at least a portion of its length. Cross sections of segment 34 include cross-sections having a height dimension greater than a width dimension.;EFFECT: group of inventions is aimed at providing the possibility of reducing the size of the casing.;17 cl, 5 dwg