AXIAL TURBOMACHINE WITH LOW CLEARANCE LOSSES Russian patent published in 2013 - IPC F01D5/20 F01D11/08 

FIELD: machine building.

SUBSTANCE: axial turbomachine (1) comprises a blade system which is formed by rotor blades (3) with each of the latter having a leading edge (8) and a free blade tip (15) set in the axial direction. The blade system is surrounded by the walls (13) of annular space. The annular space walls (13) are located in close proximity to the blade tips (15) providing for radial clearance (16) between the envelope of the blade tips (15) and the inner side (14) of the annular space. Radial projection (18) is respectively provided at the rotor blades (3) on their tips (15) near their leading edges (8). There is a circular radial recession (17) near the annular space walls (13) at the inner side (14) of the annular space; the recession is situated at radial distance (16) from the blade tips' (15) envelope. The profile of radial projections at their sides turned to the radial clearance (16) is copying the profile of the radial recession in the direction of main flow through the axial turbomachine (1). The profile on the inner side (14) of the annular space has at least four curvilinear sections divided by cusps in the direction of main flow through the axial turbomachine (1). The curvature of the adjacent curvilinear sections (19, 21, 23, 24) is of different signs.

EFFECT: reducing leakages through radial clearance.

15 cl, 3 dwg