Method and system for dynamic analysis of aero-engine main bearing under maneuvering flight conditions

Abstract

The application discloses a kind of aero-engine main bearing dynamics analysis method and system under motor flight condition, method includes, the dynamics model of rotor-support system under motor flight state is established, additional excitation force size under motor flight state is calculated;According to the load distribution law of shafting under the action of additional excitation force, the support reaction force of each support and the additional inertia load borne by main bearing are extracted, the coupling mechanism of the dynamic characteristics and elastohydrodynamic lubrication characteristics of main bearing is researched, the balance condition of coupling equation is proposed, and the main bearing thermal elastohydrodynamic lubrication coupling model is established;According to the mutual contact / collision action between typical interfaces between elements in bearing, a contact / collision action model considering lubrication is established;Considering the additional inertia load varying with time, based on the established main bearing thermal elastohydrodynamic lubrication coupling model, considering the force between main bearing interfaces, numerical integration is used to solve, realize the accurate analysis of the dynamic characteristics and vibration response mechanism of aero-engine main bearing.

Description

Technical Field

[0001] This invention belongs to the field of mechanical engineering and relates to a method and system for dynamic analysis of the main bearing of an aero-engine under maneuvering flight conditions. Background Technology

[0002] The main bearing of an aero-engine is a supporting component of the aero-engine rotor system and a critical component affecting engine safety. The quality of the main bearing directly impacts the engine's lifespan and reliability. Aero-engine main bearings generally include the low-pressure compressor rotor front bearing, low-pressure compressor rear bearing, high-pressure compressor front bearing, high-pressure turbine rear bearing, and low-pressure turbine rear bearing. Their operating environment is extremely harsh, requiring them to operate at high speeds of tens of thousands of revolutions per minute while enduring various forms of stress, friction, and extremely high temperatures, leading to frequent malfunctions. Furthermore, because fighter jets often perform complex maneuvers such as dives, turns, and rolls, the engine rotor is subjected to additional loads, potentially causing significant vibrations in the otherwise stable engine rotor system. The prominent vibrations of aero-engine main bearings during maneuvering flight, with their unclear dynamic mechanisms, severely restrict the improvement of aero-engine safety and reliability.

[0003] Establishing an analytical model for the main bearing of an aero-engine is crucial for conducting dynamic analysis of the main bearing. The analytical models of bearings can be mainly divided into quasi-static models, quasi-dynamic models, and dynamic models. The quasi-static method based on force balance was first applied to bearing analytical models. In 1960, American scholar Jones (JONES A BA general theory forelastically constrained ball and radial roller bearings under arbitrary load and speed conditions[J]. Journal of Fluids Engineering, 1960, 82(2):309-320) established static equilibrium equations and static moment equilibrium equations that take into account centrifugal force and gyroscopic torque by analyzing the forces and torques acting on the rolling balls in the ball bearing based on the raceway control assumption. Harris (HARRIS TA, AARONSON S. An analytical investigation of cylindrical roller bearings having annular rollers[J]. AS L E Transactions, 1967, 10(3):235-242) improved the quasi-static model based on Jones' theory, considering the traction effect caused by lubricating oil and the cage action, thus promoting the development of bearing analysis models to the quasi-dynamic method stage. The quasi-dynamic method replaces the static moment balance equation with the motion differential equation, which can simulate the rotation and slippage behavior of bearing components. The dynamic model describes the motion of bearing components using differential equations, which can realize the simulation of the operating state and stability analysis of bearing components under time-varying speed and load conditions. Although the quasi-dynamic model can analyze the dynamic characteristics of rolling elements, the motion assumptions used in the solution can only obtain the steady-state solution of the equation, which limits its simulation capability in terms of time-varying load and speed conditions as well as transient forces inside the bearing.

[0004] The dynamic model describes the motion of bearing elements using differential equations, enabling simulation and stability analysis of bearing element operation under time-varying speed and load conditions. Walters (WALTERS C T. The dynamics of ball bearings[J]. Journal of Tribology, 1971, 93(1): 1-10) first proposed a dynamic modeling method for rolling bearings and established a 4-DOF ball bearing dynamic model. Subsequently, Gupta (Gupta P K. Advanced dynamics of rolling elements[M]. Springer Science & Business Media, 2012) established a more comprehensive dynamic model, which can be used to analyze cage whirling, transient motion of elements, and interactions. Deng Si'er et al. (CUI Y, DENG S, DENG K, et al. Experimental study on impact of roller imbalance on cage stability[J]. Chinese Journal of Aeronautics, 2021, 34(10): 248-264) of Henan University of Science and Technology established a dynamic characteristic analysis model for cylindrical roller bearings and conducted theoretical and experimental research on the vibration characteristics caused by roller dynamic imbalance. Han Q, LI X, CHU F. Skidding behavior of cylindrical roller bearings under time-variable load conditions[J]. International Journal of Mechanical Sciences, 2018, 135: 203-214, Tsinghua University, studied the slippage behavior of cylindrical roller bearings under time-variable load conditions. Tu Wenbing et al. (UW, LUO Y, YU W. Dynamic interactions between the rolling element and the cage in rolling bearing under rotational speed fluctuation conditions[J]. Journal of Tribology-Transactions of the Asme, 2019, 141(9): 899-909), East China Jiaotong University, established a nonlinear dynamic model of rolling bearings under rotational speed fluctuation conditions. This model can consider the interaction between the roller and the cage, as well as the lubrication contact between the roller and the raceway.

[0005] Based on the analysis of the above research results, current rolling bearing dynamic models often rely on empirical values ​​or fitting formulas to calculate certain process variables, such as oil film thickness and traction coefficient. These variables are coupled with parameters such as load, speed, viscosity, temperature, and geometry, and exhibit time-varying characteristics under unsteady conditions, thus affecting the dynamic characteristics of rolling bearings under these conditions. Aero-engine main bearings operate under highly variable conditions and in complex service environments. During aircraft maneuvers such as pitch, roll, and yaw, the main bearings operate under unsteady conditions, making it impossible for existing dynamic simulation methods to accurately simulate the operating state of the main bearings during maneuvering flight.

[0006] In summary, current modeling research on dynamic characteristics mainly focuses on steady-state conditions, and some studies on unsteady-state conditions also focus on single physical fields, with little attention paid to the influence of thermal effects, lubricating medium flow state, and the coupling effect between bearing element elastic deformation on bearing dynamic characteristics. Furthermore, research on the additional inertial loads caused by maneuvering flight has not yet been conducted, making it impossible to accurately simulate the impact of maneuvering flight on the dynamic characteristics of main bearings. Therefore, there is an urgent need to establish a main bearing dynamic model that considers thermal effects and lubricating medium flow state, as well as an efficient solution algorithm, to achieve accurate analysis of the dynamic characteristics and vibration response mechanism of aero-engine main bearings under maneuvering flight loads. Summary of the Invention

[0007] The purpose of this invention is to provide a dynamic analysis method for aero-engine main bearings under maneuvering flight conditions to solve one or more of the aforementioned technical problems. The analysis method of this invention considers the effects of unsteady loads such as inertial loads, unbalanced loads, and gyroscopic torques on the main bearings under maneuvering flight conditions. It establishes a dynamic model of the main bearing considering thermal effects and the flow state of the lubricating medium, as well as an efficient solution algorithm, to achieve accurate analysis of the dynamic characteristics and vibration response mechanism of aero-engine main bearings. It essentially reveals the generation mechanism and dynamic characteristics of the vibration response of aero-engine main bearings under maneuvering flight conditions.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: a method for dynamic analysis of the main bearing of an aero-engine under maneuvering flight conditions, comprising the following steps:

[0009] S1 collects and acquires the attribute parameters and operating status of the rotor system, bearings, and rotor disk of the aero-engine;

[0010] S2. Based on the attribute parameters and operating status of the rotor system, bearings, and rotor disk of the aero-engine, and considering the motion states under different maneuvering flight conditions, a dynamic model of the aero-engine rotor-support system under maneuvering flight conditions is established. Based on the dynamic model of the aero-engine rotor-support system, the magnitude of the additional excitation force generated by the maneuvering flight is calculated. The load distribution law of the shaft system under the action of the additional excitation force is analyzed, and the support reaction force at each support is extracted, that is, the additional inertial load on the main bearing.

[0011] S3, for the complex dynamic modeling of the main bearing of aero-engine, establishes an analysis model that considers thermal effects and the flow state of the lubricating medium, namely the thermo-elastohydro-lubricating coupling model.

[0012] S4. The mutual contact / collision between typical interfaces of components in the main bearing is analyzed, and a contact / collision model considering lubrication is established.

[0013] S5 considers the additional inertial load on the main bearing of the S2 that varies with time, including inertial force and torque. It couples the thermo-elastohydro-lubricating coupling model established in S3 with the contact / collision action model considering lubrication obtained in S4, and solves it by numerical integration to realize the analysis of the dynamic characteristics and vibration response of the main bearing of the aero-engine.

[0014] Furthermore, in S1, the attribute parameters of the rotor and disk include: geometric dimension parameters and material property parameters; the attribute parameters of the bearing include: geometric dimension parameters, material property parameters, mounting position, preload, initial contact angle, axial clearance / radial clearance, and number of balls; the motion parameters include the rotor's rotational speed and the motion load spectrum of the maneuvering flight.

[0015] Furthermore, in S2, based on the property parameters and operating parameters of the rotor system, bearings, and disk, the Lagrange method is used to establish the dynamic model of the aero-engine rotor-support system under maneuvering flight conditions as follows:

[0016]

[0017] Q = F e +F b +F z +F B +G e

[0018] In the formula: M is the system mass matrix; C is the system damping matrix; G is the system gyroscope matrix; K is the system stiffness matrix; q t For the generalized displacement of the system; F e F is the vector of unbalanced forces. b G is the air excitation force vector; G is the oil film force vector of the extrusion oil film damper; e ω is the gravitational vector; ω is the rotational speed of the shaft, CB For the additional damping matrix; K B For the additional stiffness matrix; F B This is the additional excitation force vector.

[0019] Furthermore, S3 specifically includes: based on the elastohydrodynamic lubrication theory, combined with the Reynolds equation, film thickness equation and fluid energy equation, the oil film thickness distribution and pressure distribution in the contact area are obtained using the multigrid method; the thermoelastic deformation of the bearing element is calculated based on the thermoelastic mechanics theory; and the results are substituted into the film thickness equation of the elastohydrodynamic calculation module for iterative calculation until the interface continuity condition is met.

[0020] Furthermore, in S4, the additional inertial load is applied to the bearing as an external load, and a complex dynamic analysis model of the main bearing is constructed that takes into account the internal lubrication state, thermoelastic deformation, and the contact / collision between bearing elements.

[0021] Furthermore, S4 specifically includes: constructing a dynamic model of the rolling angular contact ball bearing using the Gupta full dynamic model, and solving for the contact micro-region parameters and kinematic parameters between the rolling elements and the inner / outer raceways, which serve as input conditions for the main bearing elastohydrodynamic lubrication model;

[0022] The lubrication state of the bearing is simulated using a thermo-elastohydrodynamic lubrication model. Based on the governing equations of the two-dimensional thermo-elastohydrodynamic lubrication problem, the Reynolds equations for the rolling elements and inner ring oil film considering thermal effects are obtained.

[0023] The calculation methods for the contact forces between the rolling elements and the inner and outer rings are based on Hertz contact theory. The calculation methods for the frictional forces between the rolling elements and the inner and outer raceways are also based on the contact forces between the rolling elements and the inner and outer rings. The calculation methods for the collision forces and frictional forces between the rolling elements and the cage, and between the rolling elements and the cage pockets are also considered. Furthermore, lubrication contact models and impact collision models are established for the ring-rolling element and rolling element-cage interfaces.

[0024] Based on the thermo-elastohydrodynamic lubrication model that considers thermal effects, and combined with the differential equation of motion of the main bearing, the prediction results of the dynamic model are used as the input parameters of the thermo-elastohydrodynamic lubrication model, and the prediction results of the thermo-elastohydrodynamic lubrication model are fed back to the dynamic model; and the contact / collision between components are also taken into account; a complex coupled dynamic model of the main bearing of the aero-engine under maneuvering flight conditions is established.

[0025] Furthermore, S5 specifically includes: using the additional inertial load on the main bearing of the aero-engine under maneuvering flight conditions calculated in S2 as the excitation source; completing the elliptical contact thermo-elastohydrodynamic lubrication analysis based on the multi-field coupling model of the main bearing of the aero-engine established in S3; analyzing the influence law of interface nonlinearity under different loads and relative speeds based on the contact / collision action model considering lubrication established in S4; feeding back the elliptical contact thermo-elastohydrodynamic lubrication analysis and contact / collision state to the bearing dynamics analysis for iterative iteration, repeatedly iterating until the contact load obtained in the previous two iterations reaches the convergence accuracy, obtaining the dynamic response of each component of the main bearing, and outputting the internal contact force and temperature field distribution of the bearing components;

[0026] By changing the additional inertial load, the motion state, contact / collision state and other dynamic characteristics of each component in the main bearing, as well as the vibration acceleration response law of the bearing ring, are obtained by repeating the process.

[0027] It can also provide a dynamic analysis system for the main bearing of an aero-engine under maneuvering flight conditions, including an additional inertial load acquisition module, a thermo-elasto-hydro-lubrication coupling model acquisition module, a contact / collision action model acquisition module, and an analysis and solution module;

[0028] The additional inertial load acquisition module is used to consider different maneuvering flight states, establish a dynamic model of the aero-engine rotor-support system under maneuvering flight states, calculate the magnitude of the additional excitation force generated by the aero-engine rotor-support system dynamic model, analyze the load distribution law of the shaft system under the action of the additional excitation force, and extract the support reaction force at each support, that is, the additional inertial load on the main bearing.

[0029] The thermo-elasto-hydro-lubrication coupling model is used to model the complex dynamics of aero-engine main bearings. It establishes an analysis model considering thermal effects and the flow state of the lubricating medium, i.e., the thermo-elasto-hydro-lubrication coupling model.

[0030] The contact / collision model acquisition module is used to analyze the mutual contact / collision between typical interfaces of components in the main bearing and to establish a contact / collision model that takes lubrication into account.

[0031] The analysis and solution module is used to consider the additional inertial loads on the main bearing that vary with time, including inertial forces and torques. It couples a thermo-elasto-hydro-lubrication coupling model and a contact / collision model that considers lubrication. It uses numerical integration to solve the problem and realize the analysis of the dynamic characteristics and vibration response of the aero-engine main bearing.

[0032] Another computer device is provided, including a processor and a memory. The memory is used to store computer-executable programs. The processor reads the computer-executable programs from the memory and executes them. When the processor executes the programs, it can realize the dynamic analysis method of the main bearing of an aero-engine under maneuvering flight conditions described in this invention.

[0033] The present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the implementation of the aero-engine main bearing dynamics analysis method under maneuvering flight conditions described in the present invention.

[0034] Compared with the prior art, the present invention has at least the following beneficial effects: The present invention proposes a dynamic analysis method and system for the main bearing of an aero-engine under maneuvering flight conditions. This method provides a new approach to obtaining the load borne by the bearing under maneuvering flight conditions. By establishing a dynamic model of the rotor-support system under maneuvering flight conditions such as engine pitch, yaw, roll and their combinations, the constructed dynamic model is solved, the load distribution law is analyzed, and the support reaction force at each support is extracted, which is the additional inertial load borne by the main bearing, providing load input for the main bearing dynamic model.

[0035] This invention proposes a dynamic analysis method and system for aero-engine main bearings under maneuvering flight conditions. This method addresses the unsteady operating conditions of main bearings under maneuvering flight conditions by employing a dynamic approach, considering the internal lubrication state of the bearing, thermoelastic deformation, and simultaneously incorporating contact / collision interactions between components. The prediction results of the dynamic model are used as input parameters for the thermoelastic lubrication model, while the prediction results of the thermoelastic lubrication model are fed back to the dynamic model. An iterative solution method is used to update the dynamic differential equations and the control equations of thermoelastic lubrication. Finally, a complex dynamic model of the aero-engine main bearing under maneuvering flight conditions is established, enabling accurate analysis of the dynamic characteristics and vibration response mechanism of the aero-engine main bearing. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating an implementable method of the present invention.

[0037] Figure 2 A diagram illustrating the modeling method for rotor systems in a maneuvering flight environment.

[0038] Figure 3 A simplified model diagram of an aero-engine.

[0039] Figure 4 The diagram shows the thermo-elasto-hydro-lubrication coupling model of the main bearing.

[0040] Figure 5 This is a force analysis diagram of the rolling element.

[0041] Figure 6 This is a diagram showing the dynamic and vibration response characteristics of the main bearing under mechanical loads. Detailed Implementation

[0042] The present invention will now be described in detail with reference to embodiments and accompanying drawings. (See references) Figure 1 The present invention provides a method for dynamic analysis of aero-engine main bearings under maneuvering flight loads, comprising the following steps:

[0043] 1) Collect the geometric parameters, material properties, and operating conditions of the rotor-bearing-support system to provide data support for rotor system dynamics modeling;

[0044] 2) The calculation process for maneuvering flight loads is as follows: Figure 2 As shown, firstly, inertial coordinate system, body coordinate system, fixed coordinate system, low-pressure rotor coordinate system, and high-pressure rotor coordinate system are established to lay the coordinate foundation for describing the motion of the rotor system in a space maneuvering flight environment. The motion of the aircraft is regarded as the entanglement motion of the rotor system, and then the transformation relationship between the coordinate systems is determined. Using coordinate system transformation, the motion of the aircraft is converted into the motion of the rotor base.

[0045] 3) Establish a simplified model of the aero-engine, including a high-pressure rotor and a low-pressure rotor. The low-pressure rotor has linear elastic supports at both ends, while the high-pressure rotor has a linear elastic support on the left end and an intermediate bearing support on the right end. The intermediate bearing is connected to the low-pressure rotor shaft, as shown below. Figure 3 As shown; the nonlinear force of the intermediate bearing is calculated using the Hertz contact model, the shaft uses Timoshenko beam elements, and the wheel disk is discretized into a rigid disk.

[0046] Then, the kinetic energy, potential energy, and Rayleigh dissipation energy of the rotor system are calculated separately; the second type of Lagrange equation is used as shown in the following equation:

[0047]

[0048] In the formula, L = T t +T r -V,T t For translational kinetic energy, T r V is rotational kinetic energy, D is potential energy, and Q is dissipated energy. j For generalized force.

[0049] The established dynamic differential equations for the aero-engine rotor-support system under maneuvering flight conditions are as follows:

[0050]

[0051] Q = F e +F b +F z +FB +G e

[0052] In the formula: M is the system mass matrix; C is the system damping matrix; G is the system gyroscope matrix; K is the system stiffness matrix; q t For the generalized displacement of the system; F e F is the vector of unbalanced forces. b F is the vector of air excitation force. z G is the oil film force vector of the extrusion oil film damper; e ω is the gravitational vector; ω is the rotational speed of the shaft. B For the additional damping matrix; K B For the additional stiffness matrix; F B This is the additional excitation force vector.

[0053] When establishing the dynamic differential equations of the aero-engine rotor-support system, not only rotational inertia, gyroscopic inertia, and lateral shear deformation are considered, but also mass imbalance and the deterministic motion of the foundation (including rotation and translation). Finally, the Newmark-β method is used to solve the dynamic differential equations of the aero-engine rotor-support system.

[0054] 4) Based on the dynamic model of the aero-engine rotor support system under maneuvering flight conditions, conduct support reaction force analysis of the rotor system under maneuvering load conditions; analyze the load distribution law of the shaft system under the action of additional excitation force, and extract the support reaction force at the support where the main bearing is located and the additional inertial load borne by the main bearing. Establish a mechanical model of the main support bearing of a typical rotor structure under the action of support reaction force to obtain the load distribution characteristics of the main support bearing.

[0055] 5) Taking the angular contact ball bearing of a certain type of aero-engine as an example, the additional inertial load calculated in 4) is applied to the bearing as an external load. A complex dynamic analysis model of the main bearing is constructed that considers the internal lubrication state, thermoelastic deformation, and the contact / collision between components.

[0056] a) Construction of the full dynamic model of rolling angular contact ball bearing

[0057] A dynamic model of a rolling angular contact ball bearing is constructed using the full dynamic model proposed by Gupta. The kinematic relationships between the bearing components are as follows: Figure 4 As shown, according to Newton's second law, the differential equation of motion for the bearing under high-speed rotation is as follows:

[0058]

[0059] In the formula, I1, I2, and I3 represent the principal moments of inertia of each component, ω1, ω2, and ω3 represent the angular velocities of each component, and M1, M2, and M3 represent the torques applied to each component. The coupling effect between the bearing housing and the bearing can be described by the following differential equation:

[0060]

[0061] In the formula, m p c p k p These represent the mass, damping, and stiffness corresponding to the bearing housing; y p , z p These represent the displacement and deformation of the bearing housing in the horizontal and vertical directions, respectively; F py F pz These represent the forces acting on the bearing housing in the horizontal and vertical directions, respectively. By solving the above dynamic model, the contact micro-region parameters and kinematic parameters between the rolling element and the inner / outer raceway can be obtained, serving as input conditions for the elastohydrolubrication model of the main bearing.

[0062] b) Construction of the elliptical thermo-elastohydrodynamic lubrication model

[0063] Then, refer to Figure 4 A thermo-elastohydrodynamic lubrication model was used to simulate the lubrication state of the bearing. Based on the governing equations of the two-dimensional thermo-elastohydrodynamic lubrication problem, the Reynolds equations for the rolling elements and inner ring oil film considering thermal effects can be expressed as follows:

[0064]

[0065] In the formula, p 2j h is the oil film pressure between the rolling element and the inner ring. 2j Let η be the oil film thickness, η be the oil film dynamic viscosity, and ρ be the oil film density. and ρ * Equivalent quantity: Considering elastic deformation and contact geometry, the equations for the lubricating film thickness of the rolling element and the inner ring can be expressed as follows:

[0066]

[0067] In the formula, h0 is the thickness at the center of the rigid body. The equations for the thickness of the lubricating film on the rolling element and the inner ring can be solved using the multigrid method.

[0068] c) Contact / collision mechanism of bearing internal interface

[0069] The dynamic effects between the components during the movement of a rolling bearing cause changes in the contact angle between the rolling elements and the inner and outer rings of the bearing. Furthermore, there is a clearance between the rolling elements and the cage, resulting in collision contact between them during actual operation. Additionally, there is a coefficient of friction (or frictional force) between the rolling elements and the cage pockets. The force analysis of a rolling ball is as follows... Figure 5 As shown.

[0070] According to Hertz's contact theory, the magnitude of the contact force between the rolling element and the inner and outer rings can be expressed as:

[0071]

[0072] In the formula, K i K o δ is the contact stiffness coefficient between the rolling element and the inner and outer rings; i δ o The deformation is due to the contact between the rolling element and the inner and outer rings.

[0073] According to Coulomb's law of friction, frictional force is the product of the coefficient of friction and the normal contact force of the contact surface. Therefore, the magnitude of the frictional force between the rolling element and the inner and outer raceways can be expressed as:

[0074]

[0075] In the formula, μ is the coefficient of traction lubrication friction between the rolling element and the inner and outer rings.

[0076] Considering the magnitudes of the collision and friction forces between the rolling elements and the cage, the magnitudes of the collision and friction forces between the rolling elements and the cage pockets can be calculated using the following formula:

[0077]

[0078] F d =μ d N d

[0079] In the formula, K d C is the contact stiffness coefficient between the rolling element and the cage; V is the contact damping coefficient between the rolling element and the cage; d The normal relative velocity at the point of contact; μ d This is the coefficient of friction between the rolling elements and the cage.

[0080] Based on the above analysis, lubrication contact models and impact collision models are established for the interfaces of the raceway-rolling element and the rolling element-cage. Based on these interface models, the influence of nonlinear interface behavior under different loads and relative velocities is analyzed.

[0081] d) Bearing dynamics and vibration response analysis

[0082] Using the additional inertial load of the aero-engine main bearing calculated under the maneuvering flight state in 4) as the excitation source, and based on the thermo-elastohydrodynamic lubrication model considering thermal effects established in b), combined with the main bearing motion differential equations, as shown in the following equation; the prediction results of the dynamic model are used as the input parameters of the thermo-elastohydrodynamic lubrication model, and the prediction results of the thermo-elastohydrodynamic lubrication model are fed back to the dynamic model; and the contact / collision between components are also taken into account; thus, a complex coupled dynamic model of the aero-engine main bearing under the maneuvering flight state is established.

[0083] The differential equations of motion for the main bearing are shown below:

[0084]

[0085] In the formula, m is the mass of the bearing element; r is the position vector; F i For inertial load; F u For unbalanced loads; I is the inertia tensor; Ω is the revolution angular velocity; ω is the rotation angular velocity; M d M is the resistance torque; g This is the gyroscopic torque.

[0086] Finally, a numerical algorithm is used to solve for the dynamic response of each component of the main bearing, and the internal contact force distribution of the bearing components is output. This allows us to obtain the motion state, contact / collision state, and other dynamic characteristics of each component within the main bearing under different additional inertial loads, as well as the vibration acceleration response law of the bearing races. The analysis process is as follows: Figure 6 As shown.

[0087] The present invention can also provide a dynamic analysis system for the main bearing of an aero-engine under maneuvering flight conditions, including an additional inertial load acquisition module, a thermo-elasto-hydro-lubrication coupling model acquisition module, a contact / collision action model acquisition module, and an analysis and solution module;

[0088] The additional inertial load acquisition module is used to consider different maneuvering flight states, establish a dynamic model of the aero-engine rotor-support system under maneuvering flight states, calculate the magnitude of the additional excitation force generated by the aero-engine rotor-support system dynamic model, analyze the load distribution law of the shaft system under the action of the additional excitation force, and extract the support reaction force at each support, that is, the additional inertial load on the main bearing.

[0089] The thermo-elastohydro-lubrication coupling model is used to model the complex dynamics of the main bearing of aero-engines and to establish an analysis model that considers thermal effects and the flow state of the lubricating medium, namely the thermo-elastohydro-lubrication coupling model.

[0090] The contact / collision model acquisition module is used to analyze the mutual contact / collision between typical interfaces of components in the main bearing and to establish a contact / collision model that takes lubrication into account.

[0091] The analysis and solution module is used to consider the additional inertial loads on the main bearing that vary with time, including inertial forces and torques. It couples a thermo-elasto-hydro-lubrication coupling model and a contact / collision model that considers lubrication. It uses numerical integration to solve the problem and realize the analysis of the dynamic characteristics and vibration response of the aero-engine main bearing.

[0092] On the other hand, the present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the implementation of the aero-engine main bearing dynamics analysis method under maneuvering flight conditions described in the present invention.

[0093] The computer equipment may be a laptop, desktop computer, workstation, or vehicle-mounted computer.

[0094] The processor described in this invention may be a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processor (DSP), an application-specific integrated circuit (ASIC), or an off-the-shelf programmable gate array (FPGA).

[0095] The memory described in this invention can be an internal storage unit of a laptop, desktop computer, workstation, or vehicle-mounted computer, such as memory or hard disk; or it can be an external storage unit, such as a portable hard disk or flash memory card.

[0096] The present invention can also provide a computer device, including a processor and a memory, wherein the memory is used to store a computer executable program, the processor reads the computer executable program from the memory and executes it, and the processor can realize the dynamic analysis method of the main bearing of an aero-engine under maneuvering flight conditions described in the present invention when executing the computer executable program.

[0097] Computer-readable storage media can include computer storage media and communication media. Computer storage media includes volatile and non-volatile, removable and non-removable media implemented using any method or technology for storing information such as computer-readable instructions, data structures, program modules, or other data. Computer-readable storage media can include: read-only memory (ROM), random access memory (RAM), solid-state drives (SSDs), or optical discs, etc. Random access memory can include resistive random access memory (ReRAM) and dynamic random access memory (DRAM).

Claims

1. A method for dynamic analysis of aero-engine main bearings under maneuvering flight conditions, characterized in that, Includes the following steps: S1 collects and acquires the attribute parameters and operating status of the rotor system, bearings, and rotor disk of the aero-engine; S2. Based on the attribute parameters and operating states of the rotor system, bearings, and rotor disk of the aero-engine, and considering different maneuvering flight states, a dynamic model of the aero-engine rotor-support system under maneuvering flight states is established. The magnitude of the additional excitation force generated during maneuvering flight is calculated based on this dynamic model. The load distribution law of the shaft system under the action of the additional excitation force is analyzed, and the support reaction forces at each support are extracted, i.e., the additional inertial load on the main bearings. Based on the attribute parameters and operating parameters of the rotor system, bearings, and rotor disk, the Lagrange method is used to establish the dynamic model of the aero-engine rotor-support system under maneuvering flight states as follows: In the formula: The system quality matrix; Here is the system damping matrix; The system gyroscope matrix; Here is the system stiffness matrix; For the generalized displacement of the system; This is the vector of unbalanced forces; It is the vector of air excitation force; The oil film force vector of the squeeze oil film damper; It is the gravity vector; The rotational speed of the shaft. For the additional damping matrix; For the additional stiffness matrix; For the additional excitation force vector; S3, for the complex dynamic modeling of the main bearing of aero-engine, establishes an analysis model that considers thermal effects and the flow state of the lubricating medium, namely the thermo-elastohydro-lubricating coupling model. S4. The mutual contact / collision between typical interfaces of components in the main bearing is analyzed, and a contact / collision model considering lubrication is established. S5 considers the additional inertial load on the main bearing of the S2 that varies with time, including inertial force and torque. It couples the thermo-elastohydro-lubricating coupling model established in S3 with the contact / collision action model considering lubrication obtained in S4, and solves it by numerical integration to realize the analysis of the dynamic characteristics and vibration response of the main bearing of the aero-engine.

2. The method for dynamic analysis of aero-engine main bearings under maneuvering flight conditions according to claim 1, characterized in that, In S1, the attribute parameters of the rotor and disk include: geometric dimension parameters and material property parameters; the attribute parameters of the bearing include: geometric dimension parameters, material property parameters, mounting position, preload, initial contact angle, axial clearance / radial clearance and number of balls; the motion parameters include the rotor's rotational speed and the motion load spectrum of the maneuvering flight.

3. The method for dynamic analysis of aero-engine main bearings under maneuvering flight conditions according to claim 1, characterized in that, S3 specifically includes: based on elastohydrodynamic lubrication theory, combined with Reynolds equation, film thickness equation and fluid energy equation, the oil film thickness distribution and pressure distribution in the contact area are obtained by using the multigrid method; the thermoelastic deformation of the bearing element is calculated based on thermoelastic mechanics theory, and substituted into the film thickness equation of the elastohydrodynamic calculation module for iterative calculation until the interface continuity condition is met.

4. The method for dynamic analysis of aero-engine main bearings under maneuvering flight conditions according to claim 1, characterized in that, In S4, the additional inertial load is applied to the bearing as an external load. A complex dynamic analysis model of the main bearing is constructed that takes into account the internal lubrication state, thermoelastic deformation, and the contact / collision between bearing components.

5. The method for dynamic analysis of aero-engine main bearings under maneuvering flight conditions according to claim 1, characterized in that, S4 specifically includes: constructing a dynamic model of the rolling angular contact ball bearing using the Gupta full dynamic model, and solving for the contact micro-region parameters and kinematic parameters between the rolling elements and the inner / outer raceways, which serve as input conditions for the main bearing elastohydrodynamic lubrication model; The lubrication state of the bearing is simulated using a thermo-elastohydrodynamic lubrication model. Based on the governing equations of the two-dimensional thermo-elastohydrodynamic lubrication problem, the Reynolds equations for the rolling elements and inner ring oil film considering thermal effects are obtained. The calculation methods for the contact forces between the rolling elements and the inner and outer rings are based on Hertz contact theory. The calculation methods for the frictional forces between the rolling elements and the inner and outer raceways are also based on the contact forces between the rolling elements and the inner and outer rings. The calculation methods for the collision forces and frictional forces between the rolling elements and the cage, and between the rolling elements and the cage pockets are also considered. Furthermore, lubrication contact models and impact collision models are established for the ring-rolling element and rolling element-cage interfaces. Based on the thermo-elastohydrodynamic lubrication model that considers thermal effects, and combined with the differential equation of motion of the main bearing, the prediction results of the dynamic model are used as the input parameters of the thermo-elastohydrodynamic lubrication model, and the prediction results of the thermo-elastohydrodynamic lubrication model are fed back to the dynamic model; and the contact / collision between components are also taken into account; a complex coupled dynamic model of the main bearing of the aero-engine under maneuvering flight conditions is established.

6. The method for dynamic analysis of aero-engine main bearings under maneuvering flight conditions according to claim 1, characterized in that, S5 specifically includes: using the additional inertial load on the main bearing of the aero-engine under maneuvering flight conditions calculated in S2 as the excitation source; completing the elliptical contact thermo-elastohydrodynamic lubrication analysis based on the multi-field coupling model of the main bearing of the aero-engine established in S3; analyzing the influence law of interface nonlinearity under different loads and relative speeds based on the contact / collision action model considering lubrication established in S4; feeding back the elliptical contact thermo-elastohydrodynamic lubrication analysis and contact / collision state to the bearing dynamics analysis for iterative iteration, repeatedly iterating until the contact load obtained in the previous two iterations reaches the convergence accuracy, obtaining the dynamic response of each component of the main bearing, and outputting the internal contact force and temperature field distribution of the bearing components; By changing the additional inertial load, the motion state of each component in the main bearing, the dynamic characteristics of the contact / collision state, and the vibration acceleration response law of the bearing rings were obtained by repeating the process.

7. A dynamic analysis system for the main bearing of an aero-engine under maneuvering flight conditions, characterized in that, It includes modules for acquiring additional inertial loads, acquiring thermo-elasto-hydro-lubrication coupling models, acquiring contact / collision interaction models, and analysis and solution modules; The additional inertial load acquisition module is used to consider different maneuvering flight states and establish a dynamic model of the aero-engine rotor-support system under maneuvering flight states. Based on this dynamic model, the magnitude of the additional excitation force generated during maneuvering flight is calculated. The load distribution law of the shaft system under the action of the additional excitation force is analyzed, and the support reaction forces at each support are extracted, i.e., the additional inertial load on the main bearings. Based on the attribute parameters and operating parameters of the rotor system, bearings, and rotor disc, the Lagrange method is used to establish the dynamic model of the aero-engine rotor-support system under maneuvering flight states as follows: In the formula: The system quality matrix; Here is the system damping matrix; The system gyroscope matrix; Here is the system stiffness matrix; For the generalized displacement of the system; This is the vector of unbalanced forces; It is the vector of air excitation force; The oil film force vector of the squeeze oil film damper; It is the gravity vector; The rotational speed of the shaft. For the additional damping matrix; For the additional stiffness matrix; For the additional excitation force vector; The thermo-elasto-hydro-lubrication coupling model is used to model the complex dynamics of aero-engine main bearings. It establishes an analysis model considering thermal effects and the flow state of the lubricating medium, i.e., the thermo-elasto-hydro-lubrication coupling model. The contact / collision model acquisition module is used to analyze the mutual contact / collision between typical interfaces between components in the main bearing and to establish a contact / collision model that takes lubrication into account. The analysis and solution module is used to consider the additional inertial loads on the main bearing that vary with time, including inertial forces and torques. It couples a thermo-elasto-hydro-lubrication coupling model and a contact / collision model that considers lubrication. It uses numerical integration to solve the problem and realize the analysis of the dynamic characteristics and vibration response of the aero-engine main bearing.

8. A computer device, characterized in that, It includes a processor and a memory, the memory being used to store a computer-executable program, the processor reading the computer-executable program from the memory and executing it, and the processor executing the program being able to implement the method for dynamic analysis of the main bearing of an aero-engine under maneuvering flight conditions as described in any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, A computer-readable storage medium stores a computer program that, when executed by a processor, enables the implementation of the aero-engine main bearing dynamics analysis method under maneuvering flight conditions as described in any one of claims 1-6.

Images