摘要 |
An aerofoil array for a gas turbine system has an inner annular platform (3a) and an outer annular platform (4a), which extend about a longitudinal axis (la) and radially delimit an annular channel (5) for a gas flow; the annular channel houses a plurality of aerofoils, arranged at a substantially constant angular pitch and comprising respective central portions (7a, 7b) and respective ends (8a, 8b) connected to the platforms (3a, 4a); the aerofoils are formed by two series of aerofoils (5a, 5b) having a different geometrical feature in order to intentionally vary the eigenfreguencies and arranged about the longitudinal axis (la) with a sequence that is regularly repeated all along the annular channel (5); even though the external geometry of the aerofoils (5a, 5b) is varied, the cross-sections (9a, 9b) remain unchanged in the central portions (7a, 7b), at any given radius with respect to the longitudinal axis (la). |