CN111594317A

CN111594317A - Gas turbine engine and fan rotor support system and fusing method thereof

Info

Publication number: CN111594317A
Application number: CN201910127328.2A
Authority: CN
Inventors: 宋会英; 郑李鹏; 赵芝梅; 唐振南; 杨坤
Original assignee: AECC Commercial Aircraft Engine Co Ltd
Current assignee: AECC Commercial Aircraft Engine Co Ltd
Priority date: 2019-02-20
Filing date: 2019-02-20
Publication date: 2020-08-28
Anticipated expiration: 2039-02-20
Also published as: CN111594317B

Abstract

The invention relates to a supporting system and a fusing method of a gas turbine engine and a fan rotor thereof, wherein the supporting system comprises a bearing assembly, a first bearing part and a second bearing part, wherein the bearing assembly comprises a first bearing part and a second bearing part; a support wall, one end of which includes a first support location supporting the first bearing portion and the other end of which includes a second support location supporting the second bearing portion; the first bearing part comprises an active magnetic suspension bearing to form a fusing structure. The support system and the fusing method have the advantage of sensitive fusing, and the gas turbine engine has the advantages of good safety performance and the like.

Description

Gas turbine engine and fan rotor support system and fusing method thereof

Technical Field

The invention belongs to the technical field of gas turbine engines, and particularly relates to a gas turbine engine and a supporting system, a supporting method and a fusing method of a fan rotor of the gas turbine engine.

Background

During the operation of the aircraft engine, the fan blades are broken or fallen off due to foreign object suction or fatigue and other factors, namely, an fbo (fan Blade off) event. Immediately after the FBO event, the damaged engine should be stopped to slowly bring the engine down from a higher operating speed to windmill rotation and continue for a period of time (sometimes up to 180 minutes) during the windmill rotation phase until deceleration for safe landing is achieved when landing conditions are met. The FBO event can generate great impact collision load and unbalance load, which can cause damage to key components such as engine mounting joints and bearings, and seriously affect the safety of the key components, and aeroengine airworthiness regulations (FAR33.74 and FAR33.94) correspondingly stipulate the safety.

In order to meet the airworthiness requirement, limit load borne by key components in FBO (fiber bulk acoustic oxidizer) events is reduced, safety of an aero-engine is guaranteed, and a load relief design is introduced into the aero-engine design. A common relief design, also known as a fuse design, provides a deactivatable component (e.g., a thinned section, a necked-down bolt, etc.) at the bearing cone wall. The passive failure component is a structure with weak mechanical performance, can fail under the action of a preset load (fusing threshold), and can decouple a fan rotor from a stator supporting structure such as an intermediate casing, so that on one hand, the transmission path of FBO load is changed, on the other hand, the critical rotating speed of the rotor is reduced to be far lower than the current working rotating speed of an engine and higher than the rotating speed of a windmill, and the rotor is in a supercritical state in a parking and decelerating stage and in a subcritical state in a windmill rotating stage so as to reduce unbalanced load; the safety of the engine is protected.

The inventor finds that for a traditional fusing structure with weak mechanical performance, when part of blades of an engine drop and transient impact load generated by the fusing structure is just lower than a fusing failure threshold value, the fusing structure cannot be instantly fused after the part of blades drop, so that the engine continues to operate, and the generated load may exceed the transient impact load generated by the dropping of fan blades, so that a larger limit load is caused, higher design requirements are provided for various component systems, and the difficulty and the cost of engine design are increased. In addition, the engine continues to operate after the falling event occurs, and the blades and the casing are possibly collided and rubbed, even a fire disaster is caused. Accordingly, there is a need in the art for an instant responsive melt down gas turbine engine fan rotor support system and method of melting down to improve gas turbine engine safety.

Disclosure of Invention

It is an object of the present invention to provide a support system for a gas turbine engine fan rotor.

It is another object of the present invention to provide a gas turbine engine.

It is a further object of the present invention to provide a method of fusing a gas turbine engine fan rotor.

A support system for a fan rotor of a gas turbine engine according to one aspect of the present invention includes a bearing assembly including a first bearing portion for supporting the fan rotor and a second bearing portion; a support wall, one end of which includes a first support location supporting the first bearing portion and the other end of which includes a second support location supporting the second bearing portion; the first bearing part comprises an active magnetic suspension bearing to form a fusing structure.

In an embodiment of the support system, the support wall comprises a first support cone wall and a second support cone wall, the small end of the first support cone wall comprising a first support location and the small end of the second support cone wall comprising a second support location, the large end of the first support cone wall being connected with the large end of the second support cone wall.

In an embodiment of the bearing system, the first bearing portion comprises a first bearing main portion comprising the active magnetic bearing and a first bearing subsection comprising a rolling bearing and an elastic support in series therewith.

In an embodiment of the support system, the resilient support is connected to the first support location by a third support cone wall, the third support wall having a large end connected to the first support wall and a small end connected to the resilient support.

In an embodiment of the support system, the rolling bearing comprised by the first bearing section is a roller bearing, which is used together with the active magnetic suspension bearing for radial constraint of a rotating shaft; the second bearing portion includes a ball bearing for providing radial and axial constraint to the shaft.

In accordance with another aspect of the present invention, a gas turbine engine, a fan rotor, a casing, and the support system of any of the above, the bearing assembly supports the fan rotor, and the casing supports the support wall.

According to one aspect of the invention, a method for fusing a fan rotor of a gas turbine engine comprises the following steps: the fan rotor is provided with a first bearing part and a second bearing part in the axial direction respectively to support the fan rotor, wherein the first bearing part is provided with a fusing structure, the fusing structure instantly responds to fusing after a fusing event of the fan rotor occurs, and the first bearing part instantly releases the support of the fan rotor.

In an embodiment of the fusing method, after the fusing structure responds to the fusing instantly, the first bearing part restores to support the fan rotor along with the restoration of the rotation axis of the fan rotor.

In an embodiment of the fusing method, the fusing structure is formed by an active magnetic suspension bearing.

In an embodiment of the fusing method, a first bearing subsection of a first bearing part is formed by connecting a rolling bearing and an elastic bearing in series, and the first bearing subsection keeps supporting the fan rotor after a fusing event of the fan rotor occurs; and arranging a fusing structure on a first bearing main part of the first bearing part, wherein the fusing structure instantly responds to fusing after a fusing event of the fan rotor occurs, and the first bearing main part instantly releases the support of the fan rotor.

In summary, the improvement effect of the present invention at least includes one of the following:

(1) the active magnetic suspension bearing is adopted, the active magnetic suspension bearing can be instantly fused after an FBO event occurs, the sensitivity is high, the load generated in the FBO speed reduction stage is not larger than the transient impact load generated by blade shedding, and the safety of a gas turbine engine is facilitated;

(2) the full fusing or partial fusing can be realized after the FBO event occurs, the load of each stage of the FBO is reduced to the greatest extent, and the applicability is wide;

(3) an active magnetic suspension bearing is adopted, and the active magnetic suspension bearing is provided with a displacement sensor, so that a sensor is not required to be additionally arranged in a fusing structure, and the system is simplified;

(4) and the active magnetic suspension bearing is adopted, and the support of the fan rotor is recovered in the windmill stage after the FBO event occurs, so that the engine can stably run until the engine is forced to descend.

Drawings

The above and other features, properties and advantages of the present invention will become more apparent from the following description of the embodiments in conjunction with the accompanying drawings, it being noted that the drawings are given by way of example only and are not drawn to scale, and should not be taken as limiting the scope of the invention which is actually claimed, wherein:

FIG. 1 is a partial schematic illustration of a gas turbine engine of an embodiment.

Fig. 2 is an enlarged schematic view of the structure according to fig. 1 at a.

FIG. 3 is a schematic diagram of an embodiment of an active magnetic suspension bearing as a fuse structure.

Detailed Description

The following discloses many different embodiments or examples for implementing the subject technology described. Specific examples of components and arrangements are described below to simplify the present disclosure, but these are merely examples and do not limit the scope of the invention. For example, if a first feature is formed over or on a second feature described later in the specification, this may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact. Additionally, reference numerals and/or letters may be repeated among the various examples throughout this disclosure. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. Further, when a first element is described as being coupled or coupled to a second element, the description includes embodiments in which the first and second elements are directly coupled or coupled to each other, as well as embodiments in which one or more additional intervening elements are added to indirectly couple or couple the first and second elements to each other.

Further, it is to be understood that the positional or orientational relationships indicated by the terms "front, rear, upper, lower, left, right", "transverse, vertical, horizontal" and "top, bottom" and the like are generally based on the positional or orientational relationships illustrated in the drawings and are provided for convenience in describing the invention and for simplicity in description, and that these terms are not intended to indicate and imply that the referenced devices or elements must be in a particular orientation or be constructed and operated in a particular orientation without departing from the scope of the invention. Also, this application uses specific language to describe embodiments of the application. The terms "inside" and "outside" refer to the inner and outer parts relative to the outline of each part itself, and the terms "first", "second", "third", and the like are used to define the parts, and are used only for the convenience of distinguishing the corresponding parts, and unless otherwise stated, the terms have no special meaning, and therefore, the scope of the present invention should not be construed as being limited. Reference throughout this specification to "one embodiment," "an embodiment," and/or "some embodiments" means that a particular feature, structure, or characteristic described in connection with at least one embodiment of the present application is included in at least one embodiment of the present application. Therefore, it is emphasized and should be appreciated that two or more references to "an embodiment" or "one embodiment" or "an alternative embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, some features, structures, or characteristics of one or more embodiments of the present application may be combined as appropriate.

Referring to fig. 1, in one embodiment, a portion of an aircraft engine includes a rotor portion including a fan rotor and a compressor rotor distributed along an axial centerline 1 of the engine; the stator part comprises a casing 6. Wherein the fan rotor comprises a fan disc 3, fan blades 2 and a fan shaft neck 4, and the compressor rotor comprises a pressurized stage compressed airAnd (5) a machine. The aircraft engine also includes a support system for the fan rotor, corresponding to the area a in fig. 1. Referring to fig. 2, which is a partial enlarged schematic structural view of the area a in fig. 1, in an embodiment, the fan rotor further includes a fan shaft 9, and the supporting system of the fan rotor includes a bearing assembly including a first bearing portion 100 and a second bearing portion 103 for supporting the fan rotor; a support wall 200 having one end 141 including a first support position for supporting the first bearing part 100 and the other end 151 including a second support position, the second bearing part 103; the first bearing portion 100 includes an active magnetic suspension bearing 8, forming a fuse structure. The components are supported relative to each other such that the bearing assembly of the support system supports the fan rotor, the support wall 200 supports the bearing assembly, and the case 6 supports the support wall 200. Referring to fig. 3, the active magnetic suspension bearing 8 includes an electromagnet 17, a displacement sensor 18, a controller 19, and a power amplifier 20, and the working principle is as follows: assuming that the current in the winding of the electromagnet 17 is I₀The suction force F generated to the rotor 16 is balanced with the gravitational force G of the rotor 16, so that the rotor 16 is in a suspended, balanced position, also referred to as a reference position. When the rotor 16 is disturbed downwards, the rotor 16 will move downwards deviating from its reference position, and the displacement sensor 18 of the active magnetic bearing 8 detects the displacement of the rotor 16 from the reference position, the controller 9 converts the displacement signal into a control signal, and the power amplifier 20 converts the control signal into a control current I₀+ Δ I, which is relative to the reference position, when the control current at that time changes by Δ I, the magnetic force of the electromagnet changes, driving the rotor back to the original equilibrium position. Therefore, in the normal operation process of the aeroengine, the active magnetic suspension bearing 8 can automatically adjust and control current according to the vibration condition in the operation process of the engine, and the stable operation of the rotor 16 is ensured. With reference to the aircraft engine structure shown in fig. 1 and 2, the fusing process of the fusing structure formed by the active magnetic suspension bearing 8 is as follows: when a fusing event occurs, such as an FBO event, and the fan rotor generates a large impact load and an unbalanced load, the fan rotor will be momentarily severely displaced from the axial centerline 1 of the engine, and the displacement sensor 18 detects a large displacement of the fan rotor, equal to or exceeding the displacementWhen the fusing threshold value preset by the active magnetic bearing 8 is reached, the control current of the active magnetic bearing 8 becomes 0 or a small value, and at this time, the attraction force F of the active magnetic bearing 8 to the fan rotor is 0 or close to 0, that is, the first bearing portion 100 loses the supporting effect on the fan rotor. It can be seen that the active magnetic bearing 8 acts as a fusing structure and is correspondingly fused immediately after the FBO event occurs, so that the supporting function of the fan rotor is immediately released. Compared with the prior art that the supporting wall is provided with the components which can fail (such as a thinning section, a necking bolt and the like) and serve as the fusing structure, the sensitivity is not high near the fusing threshold, the fusing structure cannot fail immediately, and therefore larger limit load is caused, higher design requirements are provided for each component system, the difficulty and the cost of engine design are increased, the active magnetic suspension bearing 8 serves as the fusing structure, after an FBO event occurs, instant response is carried out, the supporting of a fan rotor is immediately released, rapid fusing is achieved, the situation that the load generated in the FBO speed reduction stage is larger than the transient impact load generated by blade falling is avoided, and the safety of the aeroengine is improved. And, FBO enters the windmill stage, the position of the axis of rotation of the fan rotor is restored, the control current of the active magnetic suspension bearing 8 is also restored, thereby the support to the fan rotor is restored in the windmill stage, the engine can stably run until the airplane is successfully forced to land.

As shown in fig. 2, in some embodiments, the specific structure of the supporting wall 200 may be that the supporting wall 200 includes a first supporting conical wall 14 and a second supporting conical wall 15, the small end of the first supporting conical wall 14 is one end 141 of the supporting wall 200 including a first supporting position, the small end of the second supporting conical wall 15 is the other end 151 of the supporting wall 200 including a second supporting position, and the large end 142 of the first supporting conical wall 14 is connected with the large end 152 of the second supporting conical wall 15, and the connection is supported by the casing 6. Those skilled in the art will appreciate that other configurations exist for support wall 200 and are not limited to the configuration of the embodiment shown in fig. 2. The supporting cone wall structure is adopted, so that the supporting effect is reliable, the structure is simple, and the processing is easy.

With continued reference to fig. 2, in some embodiments, the specific structure of the first bearing portion 100 may be that the first bearing portion 100 includes a first bearing main portion 101 and a first bearing subsection 102. The first bearing main part 101 comprises an active magnetic bearing 8 as a fused structure and the first bearing subsection 102 comprises a rolling bearing 10 and an elastic support 11 in series therewith. It will be appreciated by a person skilled in the art that other configurations of the first bearing part 100 exist, for example the first bearing part 100 only has a first main bearing part 101. The advantage of providing the first bearing section 102 is that it is achieved that the first bearing section 102 maintains support of the fan rotor after an FBO event of the fan rotor has occurred. Although the elastic support 11 is connected with the rolling bearing 10 in series, the first bearing subsection 102 has lower support rigidity and limited support effect, the elastic support can play a role in limiting the excessive rubbing of the fan blades and the casing after the FBO event so as to improve the safety of the aircraft engine, and simultaneously, the stress concentration phenomenon of the second bearing part 103 caused by the immediate support release of the active magnetic suspension bearing 8 can be reduced, and the technical difficulty of the fusing design of the second bearing part 103 is reduced. In addition, the first bearing main unit 101 may be a backup bearing. In particular, the particular structure of the first bearing section 102 may also include a connection between the elastic support 11 and the first support location by means of a third support cone wall 12, the third support wall 12 being connected at its large end to the first support wall 14 and at its small end to the elastic support 11. The use of the third conical support wall 12 in connection with the resilient support 11 provides a more reliable support of the first bearing section 102. With continued reference to fig. 2, in some embodiments, the specific choice of the middle bearing of the bearing assembly may be that the rolling bearing 10 comprised by the first bearing section 102 is a roller bearing, which together with the active magnetic bearing 8 serves for radial constraint of the fan rotor; the second bearing portion 103 includes a ball bearing 13 for providing radial and axial constraint to the shaft. The scheme has a simple structure, and can reduce the design calculation difficulty. It will be appreciated by those skilled in the art that other alternatives exist for the bearing options for the first bearing portion 102 and the second bearing portion 103, and are not limited to the configuration shown in fig. 2.

From the above description, the fusing method of the fan rotor may include the following steps:

the fan rotor is axially provided with a first bearing part 100 and a second bearing part 103 respectively for supporting the fan rotor, wherein the first bearing part 100 is provided with a fusing structure, the fusing structure can be formed by an active magnetic suspension bearing 8, the fusing structure instantly responds to fusing after a fusing event of the fan rotor occurs, and the first bearing part 100 instantly releases the support of the fan rotor. After the fusing structure responds to the fusing instantly, the first bearing portion 100 recovers the support of the fan rotor along with the recovery of the rotation axis of the fan rotor. Specifically, a rolling bearing 10 may be used in series with the elastic support 11 to form a first bearing section 102 of the first bearing portion 100, the first bearing section 102 maintaining support for the fan rotor after a fan rotor fusing event; the fusing structure, which is exemplified by the active magnetic suspension bearing 8, is disposed on the first bearing main portion 102 of the first bearing portion 100, and the fusing structure instantly responds to fusing after the fusing event of the fan rotor occurs, and the first bearing main portion instantly releases the support of the fan rotor.

In summary, the fan rotor supporting system, the fusing method and the aircraft engine adopting the above embodiments have the following beneficial effects:

Although the present invention has been disclosed in the above-mentioned embodiments, it is not intended to limit the present invention, and those skilled in the art may make variations and modifications without departing from the spirit and scope of the present invention. Therefore, any modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope defined by the claims of the present invention, unless the technical essence of the present invention departs from the content of the present invention.

Claims

1. A support system for a fan rotor of a gas turbine engine, comprising:

a bearing assembly including a first bearing part and a second bearing part for supporting a fan rotor;

a support wall, one end of which includes a first support location supporting the first bearing portion and the other end of which includes a second support location supporting the second bearing portion;

the first bearing part comprises an active magnetic suspension bearing to form a fusing structure.

2. The support system of claim 1, wherein the support wall comprises a first support cone wall and a second support cone wall, the small end of the first support cone wall comprising a first support location and the small end of the second support cone wall comprising a second support location, the large end of the first support cone wall being connected to the large end of the second support cone wall.

3. The support system of claim 1 wherein the first bearing portion comprises a first bearing main portion comprising the active magnetic suspension bearing and a first bearing sub portion comprising a rolling bearing and a resilient support in series therewith.

4. A support system as claimed in claim 3 wherein said resilient support is connected to said first support location by a third support cone wall, said third support wall having a larger end connected to said first support wall and a smaller end connected to said resilient support.

5. A support system as claimed in claim 3 wherein the first bearing section comprises rolling bearings which are roller bearings which together with the active magnetic suspension bearings serve to radially constrain the fan rotor; the second bearing portion includes a ball bearing for providing radial and axial constraint to the fan rotor.

6. A gas turbine engine comprising a fan rotor, a casing, and the support system of any one of claims 1-5, wherein the bearing assembly supports the fan rotor and the casing supports the support wall.

7. A method of fusing a gas turbine engine fan rotor, comprising: the fan rotor is provided with a first bearing part and a second bearing part in the axial direction respectively to support the fan rotor, wherein the first bearing part is provided with a fusing structure, the fusing structure instantly responds to fusing after a fusing event of the fan rotor occurs, and the first bearing part instantly releases the support of the fan rotor.

8. The fusing method of claim 7, wherein the fusing structure responds to the fusing instantly, and the first bearing portion restores the support of the fan rotor as the rotation axis of the fan rotor returns.

9. The fusing method of claim 7, wherein the fusing structure is formed using active magnetic bearings.

10. The method of fusing of claim 9 wherein a first bearing segment of the first bearing portion is formed using rolling bearings in series with the elastomeric bearings, the first bearing segment maintaining support for the fan rotor after a fusing event of the fan rotor; and arranging a fusing structure on a first bearing main part of the first bearing part, wherein the fusing structure instantly responds to fusing after a fusing event of the fan rotor occurs, and the first bearing main part instantly releases the support of the fan rotor.