A method for simulating interface load of ram air turbine phase setting hanging point

Abstract

The application provides a ram air turbine pitch phase hanging point interface load simulation method, and belongs to the field of dynamics simulation. First, a ram air turbine system pitch dynamics model is established based on a three-dimensional model of a ram air turbine system. A ball to stretch contact is set at the contact position of a cam shaft of a pitch eccentric cam mechanism and a turbine rear spring seat and yoke plate shaft, and a spring unit is used to simulate turbine pitch spring. A system simulation model is established according to a turbine aerodynamic pressure calculation formula and turbine axial aerodynamic force coefficients, turbine torque coefficients and blade torsion coefficients obtained through CFD simulation in the pitch process. A data interaction interface is set in the system simulation model and the dynamics simulation model to establish a joint simulation model. The axial aerodynamic force, turbine torque and blade torque calculated by the system simulation model are input as the load of the dynamics simulation model. The turbine speed and blade pitch angle in the pitch process obtained through the dynamics model simulation are input as the system simulation model. In the joint simulation model, some components are flexibilized to simulate the real structure stiffness, and the flexibilized model is used to calculate the ram air turbine system actuator pivot hanging point and motor box pivot hanging point in the pitch impact hanging point interface load. The application solves the problem of the lack of a ram air turbine system pitch impact hanging point interface load simulation analysis method, and has a good engineering practical application prospect in the ram air turbine system pitch impact hanging point interface load simulation.

Description

Technical Field

[0001] This invention belongs to the field of dynamic simulation, specifically relating to a method for simulating the interface load at the attachment point during the pitch adjustment stage of a ram air turbine. Background Technology

[0002] The hydraulic system is one of the most important electromechanical systems in modern aircraft, playing a crucial role in achieving aircraft performance and ensuring flight safety. In the ramjet turbine system, during normal flight, actuators lock the ramjet turbine inside the cabin. In an emergency, the actuators receive a release command, ejecting it outside the cabin and locking it in the released position. The turbine is exposed to high-speed airflow, and the turbine blades extract the ramjet energy, generating rotational mechanical energy. This power is transmitted to the generator via a gear train. Under the control of the generator controller, the generator begins generating electricity, providing emergency power to the aircraft. The ramjet turbine system can provide uninterrupted emergency AC power to the aircraft when the main AC power fails; its normal operation is extremely important for ensuring flight safety.

[0003] After the ram air turbine is released outside the hatch, during the turbine's start-up and power generation process, the blade pitch angle changes due to the increase in turbine speed. When the pitch angle overshoots, the axial aerodynamic force of the blades changes abruptly, and the load on the ram air turbine system's mounting point changes abruptly as well, generating impact load.

[0004] Currently, most of the information on the pitch adjustment interface load of ram air turbine systems is obtained through experiments, which consumes a lot of manpower and resources. Since the generation mechanism of the pitch adjustment interface load and the structure of the ram air turbine system are both complex, single-discipline simulation is difficult to calculate the system's pitch adjustment interface load, and there is a lack of research on the method of calculating the pitch adjustment interface load using joint simulation. Summary of the Invention

[0005] The purpose of this invention:

[0006] To address the aforementioned issues, this invention provides a simulation method for the interface load at the attachment point during the pitch adjustment stage of a ram air turbine. A joint simulation model is established, comprising a dynamic simulation model and a system simulation model, to calculate the interface load at the attachment point of the ram air turbine system. This method solves the problem that single-discipline simulations are insufficient to calculate the interface load at the attachment point due to the complexity of the pitch adjustment interface load generation mechanism and the structure of the ram air turbine system.

[0007] Technical solution:

[0008] A simulation method for interface load at the attachment point during the pitch adjustment stage of a ram air turbine includes the following steps: 1) Establishment of a dynamic model: Dynamic modeling of the interface load at the attachment point during the pitch adjustment impact process of the ram air turbine system is carried out. The three-dimensional model of the ram air turbine system is imported, and the moving parts that need to be considered in the dynamic model are assigned material properties according to the actual structure. After reading the mass, center of mass, and moment of inertia of the simplified parts in the three-dimensional model, the load is applied in the dynamic model through the mass point method. A revolute joint is set between the blade and the turbine hub, a revolute joint is set between the input shaft and the support arm housing, a sliding joint is set between the yoke shaft and the rear spring seat, and a revolute joint is set between the actuator mounting pivot attachment point and the motor housing pivot attachment point and the ground. Fixed joints are set for the connections between the actuator, the motor housing, and the support arm. A ball-to-tension contact is set at the contact point between the cam shaft of the pitch adjustment eccentric cam mechanism and the turbine rear spring seat and the yoke shaft, defined by contact stiffness, damping, and allowable contact depth. The turbine pitch adjustment spring is simulated using spring elements, and the spring stiffness and preload are set according to the actual spring parameters.

[0009] 2) System simulation model establishment: A system simulation model of the start-up and pitch adjustment impact process of the ram air turbine system is carried out. The model includes a turbine aerodynamic pressure calculation module, a turbine axial force module, a turbine torque module, and a blade torque module. The turbine aerodynamic pressure calculation module calculates the ratio of the blade tip velocity to the incoming air velocity to obtain the blade tip speed ratio, and then obtains the aerodynamic pressure. The turbine axial force module, turbine torque module, and blade torque module calculate the turbine axial force, turbine torque, and blade torque under given wind speed and air density conditions, respectively.

[0010] 3) Establishment of joint simulation model: During the start-up and pitch adjustment stage, the pitch adjustment mechanism starts pitch adjustment after reaching a certain speed under the action of eccentric torque, spring torque and blade torque. A joint simulation model of system simulation and dynamics is established to realize the simulation of the start-up and pitch adjustment process. The turbine axial force, turbine torque and blade torque obtained from the system simulation are used as the loading input of the dynamic model, and the turbine speed and pitch angle calculated in the dynamic model are used as the loading input of the system simulation model.

[0011] 4) Load calculation at the mounting point interface: Import the modal results of key components of the ram air turbine system, create actuator mounting base, motor housing, support arm, actuator inner and outer cylinders, front connecting rod, drive shaft, and blade flexible body, and calculate and read the interface loads at the actuator mounting base pivot mounting point and the motor housing pivot mounting point.

[0012] Further, step 1) involves performing dynamic modeling of the load on the mounting point interface during the start-up and pitch adjustment impact process of the ram air turbine system in Simcenter 3D, and importing the three-dimensional model of the ram air turbine system into Simcenter 3D.

[0013] Further, step 2) involves performing a system simulation model of the start-up and pitch adjustment impact process of the ram air turbine system in Amesim.

[0014] Furthermore, in step 2), the turbine axial force module, turbine torque module, and blade torque module obtain the turbine axial force, turbine torque, and blade torque under given wind speed and air density by multiplying the axial force coefficient, turbine torque coefficient, and blade torque coefficient under different tip speed ratios and pitch angles in the CFD simulation results with the turbine aerodynamic pressure.

[0015] Further, step 3) involves setting up data interfaces in Amesim and Simcenter 3D to use the turbine axial force, turbine torque, and blade torque obtained from system simulation as inputs for loading the dynamic model.

[0016] Further, step 4) involves importing the modal results of key components of the ram air turbine system into Simcenter3D to create actuator mounting base, motor housing, support arm, actuator inner and outer cylinders, front connecting rod, drive shaft, and flexible blade body.

[0017] Furthermore, step 1) the process of establishing the dynamic model specifically includes:

[0018] 11) Open Simcenter 3D software and enter the modeling module. Import the 3D model of the ram air turbine system and switch to the motion module. In the motion module, create corresponding moving bodies for the actuator mounting base, actuator, motor housing, support arm housing, turbine hub, turbine blades, centrifugal block, centrifugal block seat, and turbine end cover. Input material properties and assign corresponding materials to the parts. Simplify the actuator, motor housing, and support arm parts except for the housing. For simplified parts, read the part mass, center of mass, and moment of inertia in the 3D model. Create mass points in Simcenter 3D, input the mass, center of mass, and moment of inertia of the corresponding parts, and set the mass points as moving bodies.

[0019] 12) Kinematic pairs are set according to the connection relationship between components. A rotary pair is set between the blade and the hub, a rotary joint is set between the input shaft and the support arm housing, a sliding pair is set between the yoke shaft and the rear spring seat, a rotary pair is set between the actuator mounting pivot and the ground, a rotary pair is set between the motor housing pivot and the ground, a fixed pair is set between the centrifugal block, the centrifugal block seat and the blade, and fixed pairs are set for the connection between the actuator, the motor housing and the support arm. The mass point and the corresponding housing are also connected by fixed pairs.

[0020] 13) Use ball-to-tension contact to simulate the contact between the eccentric camshaft of the pitch control mechanism and the turbine rear spring seat and yoke shaft. The contact stiffness is selected according to the material of the contact parts. Here, the eccentric camshaft of the pitch control mechanism is made of steel, and the turbine rear spring seat and yoke shaft are made of aluminum. Here, it is a steel-aluminum contact. Use spring units to simulate the turbine pitch control spring. Define the spring unit by spring stiffness, spring damping and spring preload.

[0021] Furthermore, step 2) of the system simulation model establishment process specifically includes:

[0022] 21) Create a turbine aerodynamic pressure calculation module in Amesim. The aerodynamic pressure calculation method is as follows:

[0023] Air dynamic pressure = ρV 2 AR

[0024] In the formula, ρ is the air density, kg / m³ 3 V is wind speed, m / s; A is turbine disk area, m² 2 R is the turbine radius, in meters.

[0025] 22) Establish the turbine axial force module, turbine torque module, and blade torque module. The calculation method is as follows:

[0026] F = F p • Aerodynamic pressure

[0027] M = M p • Aerodynamic pressure

[0028] T = T p • Aerodynamic pressure

[0029] In the formula, F is the turbine output axial force, M is the output turbine torque, T is the output blade torque, and Fp, Mp, and Tp are the turbine axial force coefficient, turbine torque coefficient, and blade torque coefficient respectively, fitted according to CFD simulation results for different tip speed ratios, blade pitch angles, and air densities; the tip speed ratio is the ratio of the tip linear velocity to the incoming flow velocity.

[0030]

[0031] In the formula, n is the turbine speed, r / s.

[0032] Furthermore, step 3) of the joint simulation model establishment process specifically includes:

[0033] 31) Create a Simcenter 3D Motion Cosim interface in Amesim, with 3 inputs and 2 outputs;

[0034] 32) In Simcenter 3D, establish an electromechanical interface, set the turbine speed and blade pitch angle as control inputs, and set the turbine axial aerodynamic force, turbine torque, and the torque of the two blades as control outputs.

[0035] Furthermore, step 4) of the load calculation process at the hanging point interface specifically includes:

[0036] 41) Perform free modal finite element simulation on the actuator mounting base, motor housing, support arm, actuator inner and outer cylinders, front connecting rod, drive shaft and blades in the ram air turbine system. Import the .rst file output by the finite element simulation into Simcenter3D to create the corresponding flexible body.

[0037] 42) Calculate and read the interface load between the actuator mounting pivot point and the motor housing pivot point.

[0038] Beneficial effects

[0039] This invention establishes a dynamic simulation model and a system simulation model of the ram air turbine system's pitch adjustment process, and achieves joint simulation by establishing a data interaction interface. It calculates the interface loads of the actuator mounting pivot point and the motor housing pivot point of the ram air turbine system under pitch adjustment impact. Attached Figure Description

[0040] Figure 1 This is a flowchart of the method of the present invention.

[0041] Figure 2 This is a schematic diagram of the internal structure of a turbine.

[0042] Figure 3 This is a schematic diagram of the dynamic simulation model of a ram air turbine system.

[0043] Figure 4 This is a schematic diagram of the simulation model of a ram air turbine system.

[0044] Figure 5 This is a schematic diagram of data interaction in a co-simulation model. Detailed Implementation

[0045] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0046] The present invention will now be described in further detail with reference to the accompanying drawings and specific examples:

[0047] One embodiment of the present invention is as follows:

[0048] A simulation method for interface load at the mounting point during the pitch adjustment stage of a ram air turbine is proposed, including the following steps:

[0049] Step 1: Establish a dynamic simulation model for the pitch adjustment process of the ram air turbine system, assign material properties to moving parts according to the actual materials; for simplified parts, establish mass points according to the mass, center of mass, and moment of inertia of the parts in the 3D model; set kinematic pairs according to the connection relationship between parts; simulate the turbine pitch adjustment spring with spring elements; simulate the contact of the pitch adjustment mechanism with ball-to-tension contact.

[0050] Preferably, step 1 involves performing dynamic simulation modeling in Simcenter 3D.

[0051] Step 2: Establish a system simulation model for the blade adjustment process of the ram air turbine system. The model is divided into an aerodynamic pressure calculation module, a turbine axial force calculation module, a turbine torque calculation module, and a blade torque module.

[0052] Preferably, step 2 involves performing system simulation modeling in Amesim.

[0053] Step 3: Set up a co-simulation interface in the dynamic model of Simcenter 3D and the system simulation model of Amesim respectively. The turbine axial force, turbine torque and blade torque obtained from the system simulation calculation are used as dynamic load inputs, and the turbine speed and blade pitch angle obtained from the dynamic simulation are used as system simulation condition inputs.

[0054] Step 4: Make the main components of the ram air turbine system flexible, and calculate and read the interface load of the actuator mounting pivot point and the motor housing pivot point based on the co-simulation model.

[0055] In this embodiment, the dynamic model establishment process in step 1 specifically includes:

[0056] Open the 3D model of the ram air turbine system and save it as a .xt file. Open Simcenter 3D software, enter the modeling module, import the 3D model of the ram air turbine system, and switch to the motion module. In the motion module, create corresponding moving bodies for components such as the actuator mounting base, actuator, motor housing, support arm housing, turbine hub, turbine blades, centrifugal mass, centrifugal block seat, and turbine end cover. Input material properties and assign corresponding materials to the components. For simplified components inside the actuator, motor housing, and support arm, read the component's mass, center of mass, and moment of inertia from the 3D model, create mass points in Simcenter 3D, input the corresponding component's mass, center of mass, and moment of inertia, and set the mass points as moving bodies. Kinematic pairs are set up according to the connection relationship between components. A revolute joint is set between the blade and the hub, a rotary joint is set between the input shaft and the support arm housing, a sliding joint is set between the yoke shaft and the rear spring seat, a revolute joint is set between the actuator mounting pivot and the ground, a revolute joint is set between the motor housing pivot and the ground, and a fixed joint is set between the centrifugal block, centrifugal block seat and the blade. Fixed joints are set for the connections between the actuator, the motor housing and the support arm. The mass point and the corresponding housing are also connected by fixed joints. The contact between the eccentric camshaft of the pitch control mechanism and the turbine rear spring seat and the yoke shaft is simulated by ball-to-tension contact. The contact stiffness is selected according to the material of the contacting components. Here, the eccentric camshaft of the pitch control mechanism is made of steel, and the turbine rear spring seat and the yoke shaft are made of aluminum. Here, it is a steel-aluminum contact. Spring elements are used to simulate the turbine pitch control spring. The spring element is defined by the spring stiffness, spring damping and spring preload.

[0057] In this embodiment, step 2, the system simulation model process specifically includes:

[0058] In Amesim, create a turbine aerodynamic pressure calculation module, select the "FXYZ" component, and enter the aerodynamic pressure calculation formula as follows:

[0059] Air dynamic pressure = ρV 2 AR

[0060] In the formula, ρ is the air density, kg / m³ 3 V is wind speed, m / s; A is turbine disk area, m² 2 R is the turbine radius, in meters.

[0061] Create turbine axial force, turbine torque, and blade torque modules, select the "NDFXA0" component, input CFD simulation results, and output turbine axial force, turbine torque, and blade torque. The calculation method is as follows:

[0062] F = F p • Aerodynamic pressure

[0063] M = M p • Aerodynamic pressure

[0064] T = T p • Aerodynamic pressure

[0065] In the formula, F is the turbine axial force, M is the turbine torque, and T is the blade torque. p M p T p These represent the turbine axial force coefficient, turbine torque coefficient, and blade torque coefficient, fitted based on CFD simulation results for different tip speed ratios, blade pitch angles, and air densities. The tip speed ratio is the ratio of the tip linear velocity to the incoming flow velocity.

[0066]

[0067] In the formula, n is the turbine speed, r / s.

[0068] In this embodiment, step 3, the joint simulation model establishment process specifically includes:

[0069] In Amesim, a Simcenter 3D Motion Cosim interface is created. The number of inputs is set to 3, which are turbine axial force, turbine torque and blade torque. The number of outputs is set to 2, which are turbine speed and blade pitch angle.

[0070] In Simcenter 3D, establish an electromechanical interface. The control inputs set the turbine speed and pitch angle, with clockwise rotation as the positive direction and feathering as the positive direction. The control outputs set the turbine axial aerodynamic force, acting on the turbine end cap axially, with end cap pressure as the positive direction; the turbine torque, with instantaneous turbine rotation as the positive direction, acting on the turbine hub; and the two blade torques, with feathering as the positive direction and opposite directions for the two blade torques.

[0071] In this embodiment, the specific process of calculating the load at the hanging point interface in step 4 includes:

[0072] Free modal finite element simulation was performed on the actuator mounting base, motor housing, support arm, actuator inner and outer cylinders, front connecting rod, drive shaft, and blades in the ram air turbine system. The .rst file output by the finite element simulation was imported into Simcenter 3D to create the corresponding flexible body. The interface loads of the actuator mounting base pivot point and the motor housing pivot point were calculated and read.

[0073] The second embodiment of the present invention is:

[0074] A simulation method for interface load at the mounting point during the pitch adjustment stage of a ram air turbine is proposed, including the following steps:

[0075] 1) Dynamic Model Establishment: Open the 3D model of the ram air turbine system and save it as a .xt file. Open Simcenter 3D software, enter the modeling module, import the 3D model of the ram air turbine system, and switch to the motion module. In the motion module, create corresponding moving bodies for components such as the actuator mounting base, actuator, motor housing, support arm housing, turbine hub, turbine blades, centrifugal mass, centrifugal block seat, and turbine end cover. Input material properties and assign corresponding materials to the components. For components omitted inside the actuator, motor housing, and support arm, read the component's mass, center of mass, and moment of inertia from the 3D model, create mass points in Simcenter 3D, input the corresponding component's mass, center of mass, and moment of inertia, and set the mass points as moving bodies. Kinematic pairs are set up according to the connection relationship between components. A revolute joint is set between the blade and the hub, a rotary joint is set between the input shaft and the support arm housing, a sliding joint is set between the yoke shaft and the rear spring seat, a revolute joint is set between the actuator mounting pivot and the ground, a revolute joint is set between the motor housing pivot and the ground, and a fixed joint is set between the centrifugal block, centrifugal block seat and the blade. Fixed joints are set for the connections between the actuator, the motor housing and the support arm. The mass point and the corresponding housing are also connected by fixed joints. The contact between the eccentric camshaft of the pitch control mechanism and the turbine rear spring seat and the yoke shaft is simulated by ball-to-tension contact. The contact stiffness is selected according to the material of the contact components. Here, it is steel and aluminum contact. Spring elements are used to simulate the turbine pitch control spring. The spring element is defined by spring stiffness, spring damping and spring preload.

[0076] 2) System simulation model establishment: In Amesim, establish a turbine aerodynamic pressure calculation module, select the "FXYZ" component, and enter the aerodynamic pressure calculation formula as follows:

[0077] Air dynamic pressure = ρV 2 AR

[0078] In the formula, ρ is the air density, kg / m³ 3 V is wind speed, m / s; A is turbine disk area, m² 2 R is the turbine radius, in meters.

[0079] Create turbine axial force, turbine torque, and blade torque modules, select the "NDFXA0" component, input CFD simulation results, and output turbine axial force, turbine torque, and blade torque. The calculation method is as follows:

[0080] F = F p • Aerodynamic pressure

[0081] M = M p • Aerodynamic pressure

[0082] T = T p • Aerodynamic pressure

[0083] In the formula, F is the turbine axial force, M is the turbine torque, and T is the blade torque. p M p T p These represent the turbine axial force coefficient, turbine torque coefficient, and blade torque coefficient, fitted based on CFD simulation results for different tip speed ratios, blade pitch angles, and air densities. The tip speed ratio is the ratio of the tip linear velocity to the incoming flow velocity.

[0084]

[0085] In the formula, n is the turbine speed, r / s.

[0086] 3) Establishment of co-simulation model:

[0087] In Amesim, a Simcenter 3D Motion Cosim interface is created. The number of inputs is set to 3, which are turbine axial force, turbine torque and blade torque. The number of outputs is set to 2, which are turbine speed and blade pitch angle.

[0088] In Simcenter 3D, establish an electromechanical interface. The control inputs set the turbine speed and pitch angle, with clockwise rotation as the positive direction and feathering as the positive direction. The control outputs set the turbine axial aerodynamic force, acting on the turbine end cap axially, with end cap pressure as the positive direction; the turbine torque, with instantaneous turbine rotation as the positive direction, acting on the turbine hub; and the two blade torques, with feathering as the positive direction and opposite directions for the two blade torques.

[0089] 4) Load calculation at the hanging point interface:

[0090] Free modal finite element simulation was performed on the actuator mounting base, motor housing, support arm, actuator inner and outer cylinders, front connecting rod, drive shaft, and blades in the ram air turbine system. The .rst file output by the finite element simulation was imported into Simcenter 3D to create the corresponding flexible body. The interface loads of the actuator mounting base pivot point and the motor housing pivot point were calculated and read.

[0091] This invention has many specific applications. The above description is only a preferred embodiment of this invention. It should be noted that for those skilled in the art, several improvements can be made without departing from the principle of this invention, and these improvements should also be considered within the scope of protection of this invention.

Claims

1. A method for simulating interface loads at mounting points during the pitch adjustment stage of a ram air turbine, characterized in that, The steps include: 1) establishing a dynamic model; 2) establishing a system simulation model; 3) establishing a co-simulation model; 4) calculating the load on the hanging point interface.

2. The simulation method for interface load at the attachment point during the pitch adjustment stage of a ram air turbine according to claim 1, characterized in that, The method specifically includes the following steps: 1) Establishing a dynamic model: Perform dynamic modeling of the interface load at the hanging point during the start-up and pitch adjustment impact process of the ram air turbine system, import the three-dimensional model of the ram air turbine system, and assign material properties to the moving parts that need to be considered in the dynamic model according to the actual structure; after reading the mass, center of mass and moment of inertia of the simplified parts in the three-dimensional model, apply them in the dynamic model through the mass point method; A revolute joint is installed between the blades and the turbine hub, and between the input shaft and the support arm housing. A sliding joint is installed between the yoke shaft and the rear spring seat. A revolute joint is installed between the actuator mounting pivot point and the motor housing pivot point and the ground. Fixed joints are installed for the connections between the actuator, motor housing, and support arm. A ball-to-tension contact is installed at the contact points between the camshaft of the pitch control eccentric cam mechanism and the turbine rear spring seat and yoke shaft, defined by contact stiffness, damping, and allowable contact depth. A spring unit is used to simulate the turbine pitch control spring, and the spring stiffness and preload are set according to the actual spring parameters. 2) System simulation model establishment: A system simulation model of the start-up and pitch adjustment impact process of the ram air turbine system is carried out. The model includes a turbine aerodynamic pressure calculation module, a turbine axial force module, a turbine torque module, and a blade torque module. The turbine aerodynamic pressure calculation module calculates the ratio of the blade tip velocity to the incoming air velocity to obtain the blade tip speed ratio, and then obtains the aerodynamic pressure. The turbine axial force module, turbine torque module, and blade torque module calculate the turbine axial force, turbine torque, and blade torque under given wind speed and air density conditions, respectively. 3) Establishment of joint simulation model: During the start-up and pitch adjustment stage, the pitch adjustment mechanism starts pitch adjustment after reaching a certain speed under the action of eccentric torque, spring torque and blade torque. Establish a joint simulation model of system simulation and dynamics to realize the simulation of the start-up and pitch adjustment process. The turbine axial force, turbine torque, and blade torque obtained from the system simulation are used as the loading inputs of the dynamic model, and the turbine speed and blade pitch angle calculated in the dynamic model are used as the loading inputs of the system simulation model. 4) Load calculation at the mounting point interface: Import the modal results of key components of the ram air turbine system, create actuator mounting base, motor housing, support arm, actuator inner and outer cylinders, front connecting rod, drive shaft, and blade flexible body, and calculate and read the interface loads at the actuator mounting base pivot mounting point and the motor housing pivot mounting point.

3. The simulation method for interface load at the attachment point during the pitch adjustment stage of a ram air turbine according to claim 2, characterized in that, Step 1) is to perform dynamic modeling of the load on the mounting point interface during the start-up and pitch adjustment impact process of the ram air turbine system in Simcenter 3D. Import the 3D model of the ram air turbine system into Simcenter 3D.

4. The simulation method for interface load at the attachment point during the pitch adjustment stage of a ram air turbine according to claim 3, characterized in that, Step 2) involves performing a system simulation model of the start-up and pitch adjustment impact process of the ram air turbine system in Amesim.

5. The simulation method for interface load at the attachment point during the pitch adjustment stage of a ram air turbine according to claim 5, characterized in that, In step 2), the turbine axial force module, turbine torque module, and blade torque module obtain the turbine axial force, turbine torque, and blade torque under given wind speed and air density by multiplying the axial force coefficient, turbine torque coefficient, and blade torque coefficient under different tip speed ratios and pitch angles in the CFD simulation results with the turbine aerodynamic pressure.

6. The simulation method for interface load at the attachment point during the pitch adjustment stage of a ram air turbine according to claim 5, characterized in that, Step 3) is to set up the data interface in Amesim and Simcenter 3D and use the turbine axial force, turbine torque and blade torque obtained from the system simulation as the input for loading the dynamic model.

7. The simulation method for interface load at the attachment point during the pitch adjustment stage of a ram air turbine according to claim 6, characterized in that, Step 4) involves importing the modal results of key components of the ram air turbine system into Simcenter3D to create actuator mounting base, motor housing, support arm, actuator inner and outer cylinders, front connecting rod, drive shaft, and flexible blade body. Step 4) The calculation process for the load at the hanging point interface specifically includes: 41) Perform free modal finite element simulation on the actuator mounting base, motor housing, support arm, actuator inner and outer cylinders, front connecting rod, drive shaft, and blades in the ram air turbine system. Import the .rst file output by the finite element simulation into Simcenter 3D to create the corresponding flexible body. 42) Calculate and read the interface load between the actuator mounting pivot point and the motor housing pivot point.

8. The simulation method for interface load at the attachment point during the pitch adjustment stage of a ram air turbine according to claim 7, characterized in that, Step 1) The process of establishing the dynamic model specifically includes: 11) Open Simcenter 3D software and enter the modeling module. Import the 3D model of the ram air turbine system and switch to the motion module. In the motion module, create corresponding moving bodies for the actuator mounting base, actuator, motor housing, support arm housing, turbine hub, turbine blades, centrifugal block, centrifugal block seat, and turbine end cover. Input material properties and assign corresponding materials to the parts. Simplify the actuator, motor housing, and support arm parts except for the housing. For simplified parts, read the part mass, center of mass, and moment of inertia in the 3D model. Create mass points in Simcenter 3D, input the mass, center of mass, and moment of inertia of the corresponding parts, and set the mass points as moving bodies. 12) Kinematic pairs are set according to the connection relationship between components. A rotary pair is set between the blade and the hub, a rotary joint is set between the input shaft and the support arm housing, a sliding pair is set between the yoke shaft and the rear spring seat, a rotary pair is set between the actuator mounting pivot and the ground, a rotary pair is set between the motor housing pivot and the ground, a fixed pair is set between the centrifugal block, the centrifugal block seat and the blade, and fixed pairs are set for the connection between the actuator, the motor housing and the support arm. The mass point and the corresponding housing are also connected by fixed pairs. 13) Use ball-to-tension contact to simulate the contact between the eccentric camshaft of the pitch control mechanism and the turbine rear spring seat and yoke shaft. The contact stiffness is selected according to the material of the contact parts. Here, the eccentric camshaft of the pitch control mechanism is made of steel, and the turbine rear spring seat and yoke shaft are made of aluminum. Here, it is a steel-aluminum contact. Use spring units to simulate the turbine pitch control spring. Define the spring unit by spring stiffness, spring damping and spring preload.

9. The simulation method for interface load at the attachment point during the pitch adjustment stage of a ram air turbine according to claim 8, characterized in that, Step 2) The system simulation model establishment process specifically includes: 21) Create a turbine aerodynamic pressure calculation module in Amesim. The aerodynamic pressure calculation method is as follows: Air dynamic pressure = ρV 2 AR In the formula, ρ is the air density, kg / m³ 3 V is wind speed, m / s; A is turbine disk area, m² 2 R is the turbine radius, in meters. 22) Establish the turbine axial force module, turbine torque module, and blade torque module. The calculation method is as follows: F = F p • Aerodynamic pressure M = M p • Aerodynamic pressure T = T p • Aerodynamic pressure In the formula, F is the turbine output axial force, M is the output turbine torque, T is the output blade torque, and Fp, Mp, and Tp are the turbine axial force coefficient, turbine torque coefficient, and blade torque coefficient respectively, fitted according to CFD simulation results for different tip speed ratios, blade pitch angles, and air densities; the tip speed ratio is the ratio of the tip linear velocity to the incoming flow velocity. In the formula, n is the turbine speed, r / s.

10. The simulation method for interface load at the attachment point during the pitch adjustment stage of a ram air turbine according to claim 9, characterized in that, Step 3) The process of establishing the co-simulation model specifically includes: 31) Create a Simcenter 3D Motion Cosim interface in Amesim, with 3 inputs and 2 outputs; 32) In Simcenter 3D, establish an electromechanical interface, set the turbine speed and blade pitch angle as control inputs, and set the turbine axial aerodynamic force, turbine torque, and the torque of the two blades as control outputs.

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