Self-adaptive control structure and adjusting method for pressure of rear unloading cavity of gas compressor rotor

Abstract

The invention provides a compressor rotor rear unloading cavity pressure self-adaptive control structure and an adjusting method, and the compressor rotor rear unloading cavity pressure self-adaptive control structure comprises a high-pressure compressor stator, a labyrinth sealing honeycomb, a high-pressure compressor rotor and a main combustion chamber, the self-adaptive control structure for the pressure of the rear unloading cavity of the gas compressor rotor further comprises a deflation device which is connected with the unloading cavity of the main combustion chamber. The self-adaptive deflation device is additionally arranged at the outlet section of the unloading cavity, the deflation area is automatically adjusted by sensing the gas pressure of the unloading cavity, the pressure and the deflation amount of the unloading cavity are changed, and then axial force self-adaptive adjustment under different engine states is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of aeroengines, and in particular to a pressure adaptive control structure and a regulating method for a compressor rotor rear unloading cavity. Background Art

[0002] The axial force of the gas turbine rotor is one of the important indicators of the overall design of the gas turbine. The axial force should not be too large or too small. If the axial force is too large, it will not only affect the bearing life, but even make the bearing itself difficult to bear; if the axial force is too small, the axial force may be reversed in different working conditions, causing bearing slip and impact damage. The axial force of the high-pressure rotor is composed of the axial force of the compressor rotor and the axial force of the turbine rotor. The axial force (F high-pressure compressor) acting on the compressor rotor is forward, and the axial force (F high-pressure turbine) acting on the turbine rotor is backward. After the axial forces of the compressor rotor and the turbine rotor are offset, the remaining part is borne by the rotor bearing. Therefore, the axial force must be maintained at a suitable load so that the axial force acting on the bearing is of appropriate size and does not reverse. Research and actual measurements show that the engine axial force and its operating conditions, the throat area of ​​the turbine guide, the sealing structure, etc. are all key factors affecting the axial force. The traditional means of adjusting the engine axial force mainly include adjusting the sealing diameter, the throat area of ​​the turbine guide, and the sealing clearance of each sealing cavity. Among them, the main means of regulating the axial force of high-load compressors is to add a grate seal plate behind the compressor rotor to establish an axial force control cavity (hereinafter referred to as the unloading cavity), and to design the axial force of the compressor rotor by designing the grate seal gap and the unloading cavity venting area. This method has the following problems: 1) The axial force adjustment is very sensitive to the gap between the grate teeth and the seal, and the gap design and manufacturing control are difficult. If the gap between the grate teeth and the seal is too large, the axial force will be too large and the bearing will be overloaded. If the gap between the grate teeth and the seal is too small, the grate teeth and the seal will collide and rub, increasing the risk of vibration and wear. 2) The axial force requirements under different conditions vary greatly and cannot be met at the same time. When the comb teeth sealing gap is constant, increasing the venting area of ​​the unloading cavity can reduce the axial force to meet the axial force requirements of the engine under large conditions, but a larger venting area will lead to insufficient or even reverse axial force under low conditions. At the same time, a larger venting volume will cause a loss of engine performance under low conditions. Summary of the invention

[0003] In view of this, the present invention provides a compressor rotor rear unloading chamber pressure adaptive control structure and adjustment method to achieve adaptive adjustment of axial force under different engine states, effectively improving the engine's operating reliability and performance.

[0004] The present invention provides the following technical solution: a compressor rotor rear unloading chamber pressure adaptive control structure, comprising: a high-pressure compressor stator, a comb-teeth sealing honeycomb, a high-pressure compressor rotor, and a main combustion chamber. The compressor rotor rear unloading chamber pressure adaptive control structure also includes a venting device, which is connected to the unloading chamber of the main combustion chamber.

[0005] Furthermore, the air release device includes: a shell fixedly connected to the main combustion chamber, the shell having an inner cavity; a piston assembly arranged in the inner cavity, the piston assembly is arranged radially along the inner cavity, and the piston assembly can slide axially along the inner cavity.

[0006] Furthermore, the shell is provided with: a normally open through hole, which is provided at one end of the shell away from the main combustion chamber; and a venting through hole, which is provided at one end of the shell close to the main combustion chamber.

[0007] Furthermore, there are multiple normally open through holes and venting through holes, which are distributed at intervals along the outer circumference of the shell.

[0008] Furthermore, each normally open through hole is a circular hole or a rectangular hole; each venting through hole is a tapered hole, the extension direction of the tapered hole is parallel to the axis of the inner cavity, and the small diameter end of the tapered hole faces the main combustion chamber.

[0009] Furthermore, the piston assembly includes: a support rod, which is arranged in the shell and fixedly connected to the shell, and the support rod is provided with a accommodating cavity; a piston rod, one end of which is connected to the support rod, and one end of the piston rod can be placed in the accommodating cavity; a spring, which is sleeved outside one end of the piston rod and abuts against the support rod; and a spherical piston, which is arranged at the other end of the piston rod.

[0010] The present invention also provides a regulation method for designing the above-mentioned compressor rotor rear unloading cavity pressure adaptive control structure.

[0011] Furthermore, the adjustment method includes the following steps: step 1, calculating the axial force and performing axial force balance design; step 2, obtaining the unloading chamber venting area required at different speeds according to step 1; step 3, calculating the vent valve through hole radius and the spring stiffness according to the unloading chamber venting area.

[0012] In step 2, the formula Obtain the required unloading cavity deflation area at different speeds, where: is the venting area of ​​the unloading cavity, is the required value of axial force balance, F high pressure turbine is the turbine axial force, F bearing max is the bearing limit force of the main support point of the engine, k is a constant, is the relationship function between the unloading chamber pressure and the compressor axial force, and f (N) is the mainstream chamber pressure.

[0013] The specific step 3 of the adjustment method is: By formula Get the radius of the bleed valve hole; By formula ; ; Calculate the stiffness of the spring; Among them, R 0 is the radius of the deflation valve through hole in the initial state of the spring, m is the number of the deflation through holes (522), n is the number of the normally open through holes (521), is the central angle of the fan-shaped circle of the vent hole; L is the radius of the vent valve hole, x is the spring compression, P Q3 is the pressure of the venting device chamber, A 活塞 is the piston area.

[0014] Compared with the prior art, the beneficial effects that can be achieved by at least one of the above-mentioned technical solutions adopted by the present invention include at least the following: the present invention adds an adaptive bleed device to the outlet section of the unloading chamber, automatically adjusts the bleed area by sensing the gas pressure in the unloading chamber, changes the unloading chamber pressure and the bleed volume, and thereby realizes adaptive adjustment of the axial force under different engine states. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a schematic diagram of the compressor unloading chamber structure and air flow path; Figure 2 is a schematic diagram of the structure of the deflation device; Figure 3 is a schematic diagram of the housing structure of the air release device; Figure 4 2 is a schematic diagram of the structure of the air release hole; Figure 5 is a schematic diagram of the piston assembly structure; Figure 6 It is a schematic diagram of the process of the present invention.

[0017] Reference numerals in the figure: 1, high pressure compressor stator; 2, comb teeth sealing honeycomb; 3, high pressure compressor rotor; 4, main combustion chamber; 5, air release device; 51. Sealing gasket; 52. Housing; 53. Piston assembly; 521. Normally open through hole; 522. Vent through hole; 531. Support rod; 532. Piston rod; 533. Spherical piston; 534. Limit pin; 535. Spring. DETAILED DESCRIPTION

[0018] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0019] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0020] like Figures 1 to 5 As shown, an embodiment of the present invention provides a compressor rotor rear unloading chamber pressure adaptive control structure, comprising: a high-pressure compressor stator 1, a comb-teeth sealing honeycomb 2, a high-pressure compressor rotor 3, and a main combustion chamber 4. The compressor rotor rear unloading chamber pressure adaptive control structure also includes a bleed device 5, which is connected to the unloading chamber of the main combustion chamber 4.

[0021] The present invention adds an adaptive deflation device 5 at the outlet section of the unloading chamber (Q2) to automatically adjust the deflation area (S X ), change the unloading chamber pressure and the amount of air released, thereby achieving adaptive adjustment of the axial force under different engine conditions.

[0022] The deflation device 5 comprises: The shell 52 is fixedly connected to the main combustion chamber 4 and has an inner cavity. The shell 52 is provided with a normally open through hole 521 and a venting through hole 522. The normally open through hole 521 is provided at one end of the shell 52 away from the main combustion chamber 4; the venting through hole 522 is provided at one end of the shell 52 close to the main combustion chamber 4; The piston assembly 53 is disposed in the inner cavity. The piston assembly 53 is disposed along the radial direction of the inner cavity, and the piston assembly 53 can slide along the axial direction of the inner cavity.

[0023] The piston assembly 53 can sense the pressure of the unloading chamber, thereby sliding in the inner chamber, and further controlling the opening area of ​​the air release hole 522, so as to achieve the purpose of adaptively adjusting the air release area.

[0024] It should be noted that a sealing gasket 51 is provided between the housing 52 and the main combustion chamber 4 .

[0025] Preferably, there are multiple normally open through holes 521 and multiple venting through holes 522 , which are spaced apart and distributed along the outer circumference of the shell 52 .

[0026] In the embodiment of the present invention, each normally open through hole 521 is a circular hole or a rectangular hole; each venting through hole 522 is a conical hole, the extension direction of the conical hole is parallel to the axis of the inner cavity, and the small diameter end of the conical hole faces the main combustion chamber 4.

[0027] The venting through hole 522 with a tapered hole structure can gradually increase the venting volume in the extending direction of the tapered hole, thereby adapting to the actual working conditions of the pressure of the unloading cavity behind the compressor rotor.

[0028] like Figure 5 As shown, the piston assembly 53 includes: A support rod 531 is disposed in the housing 52 and fixedly connected to the housing 52. The support rod 531 is provided with a receiving cavity; A piston rod 532, one end of which is connected to the support rod 531, and one end of the piston rod 532 can be placed in the accommodating cavity; The spring 535 is sleeved outside one end of the piston rod 532 and abuts against the support rod 531; The spherical piston 533 is disposed at the other end of the piston rod 532 .

[0029] The piston assembly 53 further includes a limiting pin 534 for limiting the piston rod 532 to prevent the piston rod 532 from falling out.

[0030] like Figure 6 As shown, the present invention also provides a regulation method for designing a pressure adaptive control structure of the rear unloading cavity of a compressor rotor, which specifically includes the following steps: (1) Calculation of axial force: The axial force of the high-pressure rotor of the engine is calculated under the high-pressure compressor rotor 3 structure. By calculating the F 高压压气机 and F 高压涡轮 , combined with the engine main support bearing limit capacity F 轴承max , evaluate whether the rotor axial force meets the requirements, F 高压压气机 and F 高压涡轮 The resultant axial force is the rotor axial force resultant (F 轴向力合力 ), that is, F 轴向力合力 =F 高压压气机 -F 高压涡轮 , generally requires 0<F 轴向力合力 <F 轴承max ; (2) Axial force balance design: F 轴向力合力 If it is greater than F 轴承max, that is, the calculated axial force is greater than the limit that the bearing can bear, then certain measures need to be taken to reduce the axial force. 轴向力合力 and F 轴承max The specific value of the rotor axial force balance requirement (F need ), F need =F 高压压气机 -F 高压涡轮 -kF 轴承max ; In order to satisfy F need , a grate disc can be added behind the compressor rotor to establish a unloading cavity that can control the axial force, and the grate tip height R, grate seal gap △, seal teeth number n and unloading cavity venting area S can be designed. X To design the compressor rotor axial force, on the basis of the determined tooth tip height R, gap △, and number of teeth n of the comb tooth plate, the pressure in the unloading chamber (Q2) is directly related to the compressor axial force, F 高压压气机 =θ*P Q2 During the test run, the pressure of the unloading chamber (Q2) can be adjusted to control the rotor axial force. The pressure of the unloading chamber (Q2) is related to the main chamber (Q1) and the discharge area of ​​the unloading chamber (S X ) is directly related to , where the main flow cavity (Q1) is directly related to the engine speed N, The pressure in the unloading chamber can be adjusted in real time by adjusting the air release area, thereby controlling the rotor axial force. is the relationship function between the unloading chamber pressure and the compressor axial force, and f (N) is the relationship function between the mainstream chamber pressure and the rotational speed.

[0031] Through simulation analysis, the rotor axial force and unloading chamber pressure P corresponding to different states of the engine during the test run are obtained. Q2 , according to the bearing limit F 轴承max , the rotor axial force F 轴向力合力 Greater than k*F 轴承max (k≤1, recommended value is 0.6~0.9) The axial force can be adjusted by adjusting the degassing area of ​​the unloading cavity. The axial force adjustment requirement is expressed as follows: ; Thus, the expression of the unloading cavity deflation area Sx is obtained: ; Therefore, the required unloading cavity venting area S at different speeds is obtained. X The higher the engine speed and state, the greater the unloading chamber pressure, and the required venting area gradually increases. When the speed is low and the state is small, the unloading chamber pressure is small, and no venting or less venting is required.

[0032] (3) Design of adaptive deflation device: Due to the unloading chamber pressure P corresponding to different states Q2 And the corresponding venting device chamber pressure P Q3 Equal P Q3 =P Q2 Therefore, it can be known that the required range of the deflation area SX of the deflation device 5 (S x-Min ~S x-MAX ) (4) Vent hole design: A plurality of normally open through holes 521 and venting through holes 522 are designed respectively. Since the venting area is related to the pressure P of the unloading chamber, Q2 The relationship is approximately exponential. The venting hole 522 of the venting device is designed to be conical. The radius of the venting valve hole is calculated by the following formula: , where R 0 is the radius of the deflation valve hole in the initial state of the spring, m is the number of deflation holes, n is the number of normally open holes, is the central angle of the fan-shaped vent hole, and the spring compression L is obtained X .

[0033] ; Spring force: ; The stiffness of the spring is: ; Thus, the main parameters of the unloading chamber pressure control device are determined.

[0034] According to the above parameters, the compressor rotor rear unloading cavity pressure adaptive control structure is manufactured and assembled.

[0035] It should be noted that S 0 is the initial deflation area of ​​the unloading cavity.

[0036] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A compressor rotor rear unloading cavity pressure adaptive control structure, comprising: A high-pressure compressor stator (1), a comb-teeth sealing honeycomb (2), a high-pressure compressor rotor (3), and a main combustion chamber (4), wherein the compressor rotor rear unloading cavity pressure adaptive control structure further includes a bleed device (5) connected to the unloading cavity of the main combustion chamber (4).

2. The compressor rotor rear unloading cavity pressure adaptive control structure according to claim 1, characterized in that: The deflation device (5) comprises: A shell (52) is fixedly connected to the main combustion chamber (4), and the shell (52) has an inner cavity; The piston assembly (53) is arranged in the inner cavity. The piston assembly (53) is arranged along the radial direction of the inner cavity, and the piston assembly (53) is able to slide along the axial direction of the inner cavity.

3. The compressor rotor rear unloading cavity pressure adaptive control structure according to claim 2 is characterized in that: The housing (52) is provided with: A normally open through hole (521) is arranged at one end of the housing (52) away from the main combustion chamber (4); The air release hole (522) is arranged at one end of the housing (52) close to the main combustion chamber (4).

4. The compressor rotor rear unloading cavity pressure adaptive control structure according to claim 3 is characterized in that: There are a plurality of normally open through holes (521) and a plurality of air release through holes (522), which are distributed at intervals along the outer circumference of the shell (52).

5. The compressor rotor rear unloading cavity pressure adaptive control structure according to claim 4, characterized in that: Each normally open through hole (521) is a circular hole or a rectangular hole; Each of the air release through holes (522) is a tapered hole, the extension direction of the tapered hole is parallel to the axis of the inner cavity, and the small diameter end of the tapered hole faces the main combustion chamber (4).

6. The compressor rotor rear unloading cavity pressure adaptive control structure according to claim 2, characterized in that: The piston assembly (53) comprises: A support rod (531) is disposed in the housing (52) and fixedly connected to the housing (52); the support rod (531) is provided with a receiving cavity; A piston rod (532), one end of which is connected to the support rod (531), and one end of the piston rod (532) can be placed in the accommodating cavity; A spring (535) is sleeved outside one end of the piston rod (532) and abuts against the support rod (531); The spherical piston (533) is arranged at the other end of the piston rod (532).

7. A method of regulation, characterized in that: Used to design a compressor rotor rear unloading cavity pressure adaptive control structure as described in any one of claims 1-6.

8. The adjustment method according to claim 7, characterized in that: The following steps are involved: Step 1: Calculate the axial force and perform axial force balance design; Step 2, according to step 1, obtaining the required degassing area of ​​the unloading cavity at different speeds; Step 3: Calculate the radius of the vent valve hole and the stiffness of the spring based on the venting area of ​​the unloading cavity.

9. The adjustment method according to claim 8, characterized in that: In step 2, the formula Obtain the required unloading cavity deflation area at different speeds, where: is the venting area of ​​the unloading cavity, is the required value of axial force balance, F high pressure turbine is the turbine axial force, F bearing max is the bearing limit force of the main support point of the engine, k is a constant, is the relationship function between the unloading chamber pressure and the compressor axial force, and f (N) is the mainstream chamber pressure.

10. The adjustment method according to claim 9, characterized in that: The step 3 is specifically as follows: By formula Get the radius of the bleed valve hole; By formula ; ; Calculate the stiffness of the spring; Wherein, R0 is the radius of the deflation valve through hole in the initial state of the spring, m is the number of the deflation through holes (522), and n is the number of the normally open through holes (521). is the central angle of the fan-shaped circle of the vent hole; L is the radius of the vent valve hole, x is the spring compression, P Q3 is the pressure of the venting device chamber, A 活塞 is the piston area.

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