CN-117052480-B - Flow area adjustable leaf type pre-rotation nozzle structure

Abstract

The invention relates to a leaf-shaped pre-rotation nozzle structure with adjustable flow area, belonging to the technical field of pre-rotation cold air systems in gas turbine engines, which adjusts the relative position of a blade back solid thin shell and a blade main body through the combined work of a micro steering engine and a connecting rod mechanism to realize the change of the flow passage area of the pre-rotation nozzle, the air conditioning system can effectively adjust the air conditioning, in the adjusting process, the two sides of the air flow channel can keep the pneumatic blade profile design of the blade back of the blade basin, so that extra pneumatic loss is avoided, different air conditioning amounts are provided for the pre-rotation air conditioning system under different working conditions, and the comprehensive fuel consumption rate of the gas turbine engine under all working conditions is reduced. When the variable cycle engine carries out component adjustment and mode switching of the main runner, the pre-rotation nozzle structure can also be adjusted in a follow-up mode, so that the thrust and safety under the full flight envelope are improved, and in addition, the pneumatic profile design is maintained in the adjusting process, so that the extra pneumatic loss is avoided.

Inventors

• LIU PENG
• DING SHUITING
• WANG CHENGHAO
• QIU TIAN
• LIU CHUANKAI
• LIU XIAOJING
• GUO JIAFAN

Assignees

• 北京航空航天大学

Dates

Publication Date

20260505

Application Date

20230912

Claims (6)

1. 1. The vane type pre-rotation nozzle structure with the adjustable flow area is characterized by comprising nozzle vanes, a bottom support plate (3) and a top support plate (4), wherein the nozzle vanes comprise vane main bodies (1) and vane back solid thin shells (2); The blade back solid thin shell (2) is movably arranged between the bottom support plate and the top support plate; The bottom support plate (3) and the top support plate (4) are annular support plates, and a plurality of groups of nozzle blades are arranged along the circumferential direction of the inner plate surfaces of the bottom support plate (3) and the top support plate (4); An airflow channel of a pre-rotation nozzle is formed between the outer peripheral wall surface of the vane back solid thin shell of each group of nozzle vanes and the inner peripheral wall surface of the vane main body of the other group of adjacent nozzle vanes; The blade back solid thin shell (2) moves between the bottom support plate (3) and the top support plate (4) along the circumferential direction of the annular support plate; in the process that the blade back solid thin shell (2) moves along the circumferential direction, the front edge of the blade back solid thin shell (2) is always kept in contact with the front edge of the blade main body (1), and a communicated solid domain is formed between the blade back solid thin shell (2) and the windward side of the blade main body (1).
2. 2. The vane-type pre-rotation nozzle structure according to claim 1, wherein the ratio of the front edge radian of the vane main body (1) to the vane basin radian of the vane main body (1) to the vane back radian of the vane back solid thin shell (2) is 2:15:12.
3. 3. The vane-type pre-rotation nozzle structure according to claim 1, characterized in that the ratio of the leading edge length of the vane back solid thin shell (2) to the vane back solid thin shell thickness D is 7.5:1.
4. 4. The vane-type pre-rotation nozzle structure according to claim 1, characterized in that the ratio of the front edge length of the vane back solid thin shell (2) to the front edge length of the vane main body (1) is 1:2.
5. 5. The vane-type pre-rotation nozzle structure as claimed in claim 1, wherein the inlet area of the air flow passage inlet is linearly inversely related to the distance of circumferential movement of the vane back solid thin shell.
6. 6. The vane-type pre-rotation nozzle structure according to claim 5, wherein the area of the air inlet of the air flow channel is in linear negative correlation with the circumferential moving distance of the vane back solid thin shell, and the expression is: Af=h*(T1-ΔS) where Af is the inlet area, h is the vane height, T1 is the inlet width of the original nozzle, and Δs is the distance of circumferential movement of the back solid thin shell.

Description

Flow area adjustable leaf type pre-rotation nozzle structure Technical Field The invention relates to the technical field of pre-swirl cooling systems in gas turbine engines, in particular to a vane-type pre-swirl nozzle structure with an adjustable flow area. Background The pre-rotation cold air system of the modern gas turbine engine provides cooling air with proper pressure and temperature for the turbine blades, thereby ensuring the reliable operation of the blades in a high-temperature gas environment and prolonging the service life of the blades. A typical pre-swirled air system directs cooling air from the annular location within the combustion chamber, through the pre-swirled nozzle, into the turbine disk forward cavity, and primarily through the turbine blade film Kong Huiru. This portion of the cold air does not participate in the thermodynamic cycle of the primary flowpath and therefore does not contribute to the output power of the gas turbine engine, and excessive bleed air of the cooling air can increase the fuel consumption of the engine and adversely affect the overall performance. Fuel consumption is an important indicator of competition in the international market for modern gas turbine engines, and therefore the negative effect of greater fuel consumption due to redundancy in cold gas volumes should be avoided as much as possible. At present, aiming at the design of a gas turbine engine, the maximum heat condition of the highest temperature level at the time of full power output is generally selected for evaluating and designing the cold air quantity demand, and the geometric parameters of the pre-rotation cold air system elements meeting the cooling requirement of turbine blades are determined under the condition. When the engine operates under the working condition of partial power output, the gas temperature level is relatively reduced, the blade cold air quantity requirement is reduced, and the cold air quantity equivalent to the maximum hot working condition is not needed to be provided, but the bleed air proportion of the cold air is basically unchanged due to the geometric fixation of elements of the pre-rotation cold air system, so that the cold air quantity is relatively redundant at the moment, and the reduction of the fuel consumption rate of the engine is not facilitated. In addition, in order to realize the flight requirements of a wide airspace and a wide speed range, the variable-cycle engine in the prior art realizes different working modes through the adjustment of the main runner component under different working states, for example, a turbofan mode is adopted at low altitude and low speed, and a turbojet mode is adopted at high altitude and high speed, wherein the problem of engine state matching in the mode switching process is involved. In the process of switching the variable cycle engine mode, the engine pre-rotation cooling system generally adopts a method of fixing the bleed air area to design She Penshe geometric parameters on the back surface, and the performance of the engine pre-rotation cooling system is improved by optimizing She Penshe geometric parameters on the back surface. However, the fixed air-entraining area can not respond to the severe change of the pneumatic parameters of the main runner component, so that the leaf basin and the leaf back can not correspondingly adjust along with the state change of the main runner component, the safety performance of key functional indexes (such as leaf disk cooling, rim sealing, axial force control and the like) of the pre-swirl air-conditioning system can not be ensured, and the instability risk of the air system is increased. Disclosure of Invention In view of the above problems, the invention provides a vane type pre-rotation nozzle structure with adjustable flow area, which can provide different cold air amounts for a pre-rotation cold air system under different working conditions so as to reduce the comprehensive fuel consumption rate of a gas turbine engine under all working conditions, and simultaneously, the invention can realize the adjustment of the flow area of the nozzle on the premise of not changing the geometrical parameters of the profile of the vane type pre-rotation nozzle with good optimized pneumatic design, the pneumatic profile design is maintained during the adjustment process, the additional loss is avoided, the pre-rotation system can also adjust along with the state change of a main runner of a variable cycle engine, and the performance and the safety under the full flight envelope are improved. The invention provides a vane-type pre-rotation nozzle structure with an adjustable flow area, which comprises nozzle blades, a bottom support plate (3) and a top support plate (4), wherein the nozzle blades comprise a blade main body (1) and a blade back solid thin shell (2); The blade main body is fixedly arranged on the bottom support plate, and the blade back solid thin shell (2) is movably