A shroud structure of the blade tip part of the impeller machinery

Abstract

The invention provides a partial shroud structure of the tip of a moving blade of a turbo machine and belongs to the technical field of turbo machines. The partial shroud structure comprises a pressure surface side stretching shroud, a suction surface side stretching shroud, front edge wings, a pressure surface near front edge wing, a suction surface near front edge wing, a pressure surface near tail edge wing, a suction surface near tail edge wing and tail edge wings. The pressure surface side stretching shroud and the suction surface side stretching shroud are width shroud structures stretching out of identical axial positions on the two sides of the blade, other components extend from the blade profile line in the outer normal direction of the blade profile line, and the components are in smooth transition. The friction contact type connection mode that a gap is reserved between the partial shrouds is adopted. The technical problem that leakage control of an existing blade tip small wing structure is limited, the weight of a totally-enclosed structure with a blade top is large and thermal loads are large are solved. The leakage amount cross a blade top is reduced effectively, a vortex structure in a blade lattice channel is improved, interaction among vortexes is weakened, and pneumatic losses in the blade lattice channel are reduced. By the adoption of the partial shroud structure, and the thermal loads of the blade top are reduced.

Description

technical field [0001] The invention belongs to the technical field of impeller machinery, and relates to a shroud structure of a blade tip part of an impeller machinery rotor blade. Background technique [0002] In turbomachinery, in order to prevent the collision and friction of moving and static parts, there will be a certain gap between the tip of the moving blade and the casing. Part of the fluid flows through the gap and flows out from the suction side under the action of the blade tip pressure and suction side pressure difference. This phenomenon is called gap leakage. The loss caused by the leakage fluid in the gap and the mixing loss with the main flow after flowing out of the gap will greatly reduce the stage efficiency of the turbomachinery. Therefore, effective control of gap leakage flow is a crucial issue in the design of modern turbomachinery. [0003] At present, the more commonly used clearance leakage control technology is to change the geometry of the bl...

AI Technical Summary

Problems solved by technology

The blade tip winglet can reduce the leakage to a certain extent, but its control effect is limited, and the generation position, strength and size of the leakage vortex do not change much, so it has little effect on improving the performance of the cascade

In addition, since the bladelets exist independently and do not contact each other, it cannot meet the requirements of the blade vibration characteristics

[0004] In summary, although the existing rotor blade tip structure has some positive effects, it still has its limitations

Images