Rim sealing structure capable of inhibiting non-uniform multi-scale gas invasion

Abstract

The invention discloses a rim sealing structure capable of inhibiting non-uniform multi-scale gas invasion. The structure comprises a high-pressure turbine guide vane end wall, a rotating static containing cavity inner gear ring, an inner gear ring baffle and a rim lateral jet hole. According to the rim sealing structure, the flow resistance of gas invasion flow is increased through a combined gap, a rotating static disc cavity is divided through the rotating static containing cavity inner gear ring, then high-temperature invasion gas is limited at a high-radius position, and the circumstancethat a wheel disc is ablated due to the fact that the high-temperature invasion gas goes deep into a disc center is avoided. A static-static system containing cavity is constructed through the inner gear ring baffle so as to reduce the tangential speed ratio of the invasion flow, the high-temperature and high-speed invasion flow is buffered, and the sealing efficiency is improved. In addition, therim lateral jet hole forms high-pressure cold air outflow, so that the sealing efficiency is improved, thermal stress distribution of the inner gear ring and the inner gear ring baffle is improved, the thermal operation deformation of a turbine disc is reduced, rubbing of a rotating static component is avoided, and the reliability of the sealing structure is improved.

Description

technical field [0001] The invention relates to a wheel rim sealing structure capable of suppressing non-uniform multi-scale gas intrusion, which is applied to a rotating static disc cavity inside a turbine rotor of a gas turbine and a wheel rim of a turbine wheel, and belongs to the technical field of gas turbine sealing. Background technique [0002] When the internal pressure of the turbine rotor-stationary disk cavity is lower than the mainstream pressure, the mainstream high-temperature gas will enter the turbine disk cavity to form gas intrusion. Due to the limitation of the material, structure and cooling method of the turbine disk, once the high-temperature gas invades the disk cavity, it will quickly ablate the surface of the disk without cooling gas protection, causing the temperature gradient between the rim and the inner diameter to increase sharply, resulting in thermal stress exceeding the disk. Design stress reserve, causing harmful deformation or even wheel b...

AI Technical Summary

Problems solved by technology

[0006] Gas turbines usually extract excess cold air from the side of the compressor to “charge” the turbine disc cavity to prevent gas intrusion. The amount of cooling air extracted from the compressor by advanced gas turbines currently in use has exceeded 18% of the inlet flow of the high-pressure compressor, which is so large The exhaust gas volume reduces the efficiency of the whole machine, increases fuel consumption, and greatly weakens the performance improvement brought about by increasing the gas temperature at the inlet of the turbine.

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