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CN-121976859-A - Double-fishhook rim sealing structure suitable for rotary-static disc cavity

CN121976859ACN 121976859 ACN121976859 ACN 121976859ACN-121976859-A

Abstract

The invention discloses a double-fishhook rim sealing structure suitable for a rotary-static disc cavity, and belongs to the field of aircraft engine rim sealing. The sealing structure comprises rotor side fishhook teeth and stator side fishhook teeth, wherein the rotor side fishhook teeth comprise rotor side main flow guide sections and rotor side cold air guide sections, so that the speed of main flow gas invasion in radial direction can be reduced, cold air can be guided to impact to the surface of the stator side fishhook teeth, and the effects of cooling and resisting gas invasion are achieved. The structure of the stator side fishhook tooth is similar to that of the rotor side fishhook tooth, the rotor side fishhook tooth comprises a stator side main flow guide section and a stator side cold air guide section, the speed direction of invasion main flow fuel gas is changed through the stator side main flow guide section and is mixed with the cold air, the stator side cold air guide section guides the cold air to enter a buffer cavity, the buffer cavity is a cavity formed by the rotor side fishhook tooth and the stator side fishhook tooth in a mutually matched mode, main flow fuel gas invading into a disc cavity is limited in the buffer cavity, and the rotor side fishhook tooth and the stator side fishhook tooth jointly act to realize rim sealing.

Inventors

  • KONG XIAOZHI
  • Shu Haocheng
  • YANG QUNJIE
  • LIU GAOWEN
  • LI YICHEN

Assignees

  • 西北工业大学
  • 四川天府新区西工大先进动力研究院

Dates

Publication Date
20260505
Application Date
20260203

Claims (10)

  1. 1. The double-fishhook rim sealing structure suitable for the rotary-static disc cavity is used for sealing the rim of the rear cavity of the turbine disc and is characterized by comprising rotor side fishhook teeth and stator side fishhook teeth which are opposite and are arranged in a staggered blending mode, wherein the rotor side fishhook teeth are positioned on the radial outer side of the stator side fishhook teeth, a buffer cavity for mixing main flow gas and cold gas is formed between the rotor side fishhook teeth and the stator side fishhook teeth, and the buffer cavity is used for limiting the main flow gas invading the disc cavity in the buffer cavity, and the double-fishhook rim sealing structure is characterized in that: The rotor side fishhook teeth are arranged on the rim of the rotor disk and face one side of the stator disk, and comprise a rotor side main stream guide section, a first outer end wall and a rotor side cool air guide section, wherein the rotor side main stream guide section is used as a radial outer wall for guiding main stream fuel gas so as to reduce the radial invasion speed of the main stream fuel gas; The stator side fishhook teeth are arranged on one side of the stator disc rim facing the rotor disc and comprise a stator side main flow guide section, a stator side cold air guide section and a second outer end wall, wherein the stator side main flow guide section is used as a radial outer wall for guiding main flow gas which invades inwards to enter the buffer cavity, the stator side cold air guide section is used as a radial inner wall for guiding cold air to enter the buffer cavity, and the second outer end wall is connected with the tail end of the stator side main flow guide section and the tail end of the stator side cold air guide section.
  2. 2. The sealing structure of the double fishhook rim of the rotor-stator chamber according to claim 1, wherein the rotor-side main flow guiding section has a slope in an axial section, the end of the slope is inclined toward the stator plate, a first included angle is formed between the slope and the axial direction, the cold air guiding section has a first curve in the axial section, the end of the cold air guiding section far away from the rotor plate is combined with the first outer end wall, a second included angle is formed between the end of the first curve and the axial direction, and the first outer end wall has a radial straight line in the axial section, and connects the end of the slope and the end of the first curve.
  3. 3. The dual fishhook rim seal adapted for use in a turntable-turntable cavity of claim 2 wherein the first angle is 3 ° -4 ° and the second angle is 20 ° -30 °.
  4. 4. The dual fishhook rim seal structure of claim 2, wherein the first curve fit formula is: ; where y 1 is the radial coordinate of the first curve and x 1 is the axial coordinate of the first curve.
  5. 5. The double fishhook rim seal adapted to a rotor-stator disc chamber of claim 1 wherein the axial length of the rotor side main flow guide section is 7-8mm and the radial thickness of the first outer end wall is 2-3mm.
  6. 6. The double fishhook rim sealing structure for the rotor-stator cavity of claim 1, wherein the stator side main flow guide section comprises a second curve and an arc which are sequentially connected in an axial section, the stator side cold air guide section is integrally biased Ping Yixian of the second curve and the arc in the axial section, the second outer end wall is axially straight in the axial section and is connected with the arc end of the stator side main flow guide section and the arc end of the stator side cold air guide section, and the stator side fishhook teeth form radial outwards turned arc sealing lips at the arc end.
  7. 7. The dual fishhook rim sealing structure of claim 6, wherein the second curve fitting formula is: ; where y 2 is the radial coordinate of the second curve and x 2 is the axial coordinate of the second curve.
  8. 8. The sealing structure of the double fishhook rim for the rotary-stationary plate cavity of claim 6, wherein the radius of the circular arc in the main flow guiding section of the stator side is 1.2-1.7mm, the included angle between the end of the circular arc and the axial direction is 60 degrees, and the axial width of the second outer end wall is 0.5-1mm.
  9. 9. The sealing structure of the double fishhook rim for the rotary-stationary plate cavity of claim 1, wherein the buffer cavity has an axial dimension of 4-5mm and a radial dimension of 2-3mm.
  10. 10. A method of designing a double fishhook rim seal adapted for use in a rotor-stator disc chamber as claimed in any one of claims 1 to 9 comprising: According to the structural size of the rotary-static disc cavity, the gap size of the rotor side fishhook tooth and the stator side fishhook tooth in fit is obtained, wherein the gap size comprises an axial distance and a radial distance; Determining the axial length of the rotor side fish hook tooth and the stator side fish hook tooth according to the axial distance, and determining the size of the buffer cavity according to the radial distance; According to the size of the buffer cavity, the shape of the rotor side fishhook tooth and the shape of the stator side fishhook tooth, the rotor side fishhook tooth and the stator side fishhook tooth are designed, the rotor side fishhook tooth is arranged at the rotor disc rim, the stator side fishhook tooth is arranged at the stator disc rim, and the rotor side fishhook tooth is positioned at the radial outer side of the stator side fishhook tooth, so that the rotor side fishhook tooth and the rotor side fishhook tooth are opposite to each other to be mixed in a staggered manner, the buffer cavity is formed, and the double fishhook rim sealing structure of the rotating static disc cavity is completed.

Description

Double-fishhook rim sealing structure suitable for rotary-static disc cavity Technical Field The invention relates to the field of aircraft engine rim sealing, in particular to a double-fishhook rim sealing structure suitable for a rotary-static disc cavity, which is used for improving sealing effect and reducing gas invasion. Background The rim sealing structure is an important component structure of the aeroengine turbine and is used for preventing high-temperature fuel gas in the cascade flow channels from invading into the disc cavity. With the continuous development of aeroengines, the temperature of the main stream before the turbine is continuously increased. The invasion of the main stream gas at too high a temperature into the disc cavity easily causes ablation of the turbine disc, thereby reducing the service life of the turbine disc and even causing serious safety accidents. In addition, the design requirements of the aero-engine are more and more complex, and the flow change range of the secondary flow of the air system is large. Therefore, how to ensure the sealing performance of the rim sealing structure under the condition of low cold air flow (such as 30% and 60% of the design point cold air flow) is a critical problem to be solved. The turbine blade cascade runner of the aero-engine is formed by alternately arranging stationary blade cascades and movable blade cascades. The stator blade is arranged on the stator disc, the movable blade is arranged on the rotor disc, the disc cavity of the front stator blade and the rear movable blade is a static-rotating disc cavity or a turbine disc front cavity (the rotor disc of the movable blade is called as a turbine disc), and on the contrary, the disc cavity of the front movable blade and the rear stator blade is a rotating-static disc cavity or a turbine disc rear cavity. The rim sealing structure of the front cavity of the turbine disc is the structure with the most extensive research, most innovation and design at home and abroad at present. There are fewer innovative designs for the turbine disk aft cavity. Because the flow field faced by the rim sealing structure of the front cavity of the turbine disk is essentially different from the flow field faced by the rim sealing structure of the rear cavity of the turbine disk, the innovative structure of the rim sealing of the front cavity of the turbine disk is difficult to exert good effect when applied to the rim sealing position of the rear cavity of the turbine disk. In a traditional turbine disc rear cavity rim sealing structure, a comb tooth arranged at the edge of a rotor disc and facing a stator disc is matched with a lining arranged at the edge of the stator disc and facing the rotor disc, an annular disc cavity is formed by the comb tooth and the radial outer side of the lining, the rotor disc and the relative inner wall of the stator disc and a rotary-static disc rim sealing structure, and high-pressure cold air between the rotor disc and the stator disc flows into the disc cavity through the matching part of the comb tooth and the lining and can play a role in preventing invasion to main stream fuel gas. This changeing quiet dish rim seal structure adopts traditional seal tooth, including rotor side seal tooth and stator side seal tooth, has certain axial clearance between the two, and its profile of tooth structure and setting have certain defect, when cold air flow variation is great, are difficult to play the seal effect, if cold air flow reduces, inflow dish chamber's air conditioning is not enough, and this structure is difficult to block mainstream gas invasion dish chamber, leads to rim and blade tenon overheated, causes the engine trouble. In order to adapt to the current wide cold air regulation situation of the current engine and prevent the flange of the rear cavity of the turbine disc from being tightly sealed under the condition of reducing cold air flow (for example, 30% -60% of the design flow), the invention provides a double fishhook tooth structure suitable for a rotating and static disc cavity. Disclosure of Invention The technical problems to be solved are as follows: In order to avoid the defects of the prior art, the invention provides the double-fishhook rim sealing structure suitable for the rotating and static disc cavity, which is designed and improved aiming at sealing of the rear rim of the turbine disc, and the sealing effect is improved and the gas invasion into the disc cavity is reduced by designing the double-fishhook tooth structure. The technical scheme is that the double-fishhook rim sealing structure suitable for the rotating static disc cavity is used for sealing the rim of the rear cavity of the turbine disc, the double-fishhook rim sealing structure comprises rotor side fishhook teeth and stator side fishhook teeth which are opposite and are in staggered blending arrangement, the rotor side fishhook teeth are positioned on the radial outer side of th