A method for extracting zonal aerodynamic loads of a spinning body aircraft component

Abstract

The application discloses a kind of spinning body aircraft component partition aerodynamic load extraction methods, first calculate the full machine surface pressure and shear stress;Then carry out fuselage partition definition;Calculate fuselage partition aerodynamic load;Carry out rudder surface partition definition;Finally calculate rudder surface partition aerodynamic load.The application realizes the fine acquisition of local aerodynamic load of key position of spinning body aircraft, can significantly improve the precision and reliability of local load environment description, to accurately identify weak link of structure, guide optimization design, effectively avoid design redundancy or deficiency.

Description

Technical Field

[0001] This invention belongs to the field of aircraft technology, specifically relating to a method for extracting aerodynamic loads in the partitions of a rotating aircraft component. Background Technology

[0002] In aircraft structural design and strength verification, accurately obtaining the actual aerodynamic load environment of each component is crucial to ensuring its safety and reliability. Traditional methods treat the aircraft as a whole for load analysis and measurement, or only roughly consider the total aerodynamic load of components such as the fuselage, rudder / wing, etc., making it difficult to accurately reflect the local aerodynamic loads borne by key areas on the surface or inside of components (such as wing leading edges, rudder hinge areas, and compartment connections) under complex flight conditions. Existing technologies cannot effectively achieve aerodynamic load decoupling and extraction from the whole to the part, and from components to zones, leading to conservative designs and an inability to accurately identify local weak points. As modern aircraft develop towards lightweight and high-performance, there is an urgent need for refined structural load analysis and zoned load extraction. Therefore, there is a pressing need to develop a method that can effectively divide component regions and accurately extract the local aerodynamic loads of each zone to support the entire process from detailed design to experimental verification, thereby improving product development efficiency and reliability. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, this invention provides a method for extracting zoned aerodynamic loads of components in a spinning aircraft. First, the surface pressure and shear stress of the entire aircraft are calculated; then, fuselage zones are defined; the aerodynamic loads of these zones are calculated; control surface zones are defined; and finally, the aerodynamic loads of the control surface zones are calculated. This invention achieves refined acquisition of local aerodynamic loads in key parts of spinning aircraft, significantly improving the accuracy and reliability of local load environment description. This allows for precise identification of structural weaknesses, guiding optimized design and effectively avoiding design redundancy or deficiencies.

[0004] The technical solution adopted by this invention to solve its technical problem is as follows: Step 1: Calculate the surface pressure and shear stress of the entire machine; Step 2: Define the chassis partitions; Step 3: Computer body section aerodynamic load; Step 4: Define the control surface partitions; Step 5: Calculate the aerodynamic loads of the control surface zones.

[0005] Preferably, step 1 specifically comprises: Based on the full-scale 3D digital model of the aircraft, a complete aerodynamic shape was obtained; the processed shape file was then imported into mesh generation software, with the coordinate system set to the origin. Located at the nose, The shaft points from the head to the tail of the machine. Axis perpendicular The axis lies in the normal plane. Axis perpendicular to For the planar model, first mesh the entire aircraft surface, then generate a spatial volume mesh. In the boundary settings, define the fuselage and rudder / wing components separately. Import the mesh file into the CFD software, set the incoming flow conditions and boundary conditions, initialize the flow field, and start the calculation. After completion, output the coordinates, pressure, and shear stress results of the entire aircraft surface.

[0006] Preferably, step 2 specifically comprises: The fuselage of the spin-type aircraft is a spin-type body, and the entire fuselage is divided into sections along both the axial and radial directions. The dividing points for the axial and radial directions are:

[0007] In the formula, For the first Axial division points coordinate, For the first Angle at each radial dividing point, from Starting from the positive direction, rotating counterclockwise is considered positive. These represent the number of segments in the axial and radial directions, respectively; partitions. The area is: .

[0008] Preferably, step 3 specifically comprises: Based on the full-scale surface coordinates exported in step 1, determine the partition to which each grid cell on the fuselage surface belongs; Grid cell center coordinates The calculation is as follows:

[0009] In the formula, This represents the total number of nodes in the grid cell; , , These are the coordinate components of the grid cell nodes; Radial angle corresponding to the center of the grid cell for:

[0010] If the following conditions are met:

[0011] Then this grid cell belongs to the first... The corresponding local aerodynamic forces are accumulated in that partition, i.e.:

[0012] In the formula, They are the first The original resultant force and resultant moment vector on the partition, These are the summation resultant force and resultant moment vector, respectively. It is the pressure at the center of the unit. It is a unit area vector. It is the shear stress vector. These are the coordinates of the torque reference point.

[0013] Preferably, step 4 specifically comprises: Before partitioning, first move the rudder plane from the global coordinate system. Transform to the local coordinate system Among them, the origin It is the intersection of the rudder shaft centerline and the rudder root chord plane. From the leading edge of the rudder root string to the trailing edge Pointing towards the rudder tip along the centerline of the rudder shaft, According to the right-hand rule, perpendicular to flat; Translate the origin of the global coordinate system to Then, after the following three rotations: The first time, around Axis rotation azimuth angle , For the rudder shaft and The angle between planes, viewed from back to front, is positive counterclockwise, corresponding to the rotation matrix. for:

[0014] After rotation rudder surface coordinates in coordinate system and shear stress It becomes:

[0015] In the formula, for Coordinate vectors in a coordinate system The origin of the control surface coordinate; The second time, Coordinate system around Axis-reverse rotation of the control surface sweep angle , The angle between the rudder axis and the fuselage cross-section is positive when it is deflected towards the tail, corresponding to the rotation matrix. for:

[0016] After rotation rudder surface coordinates in coordinate system and shear stress It becomes:

[0017] The third time, Coordinate system around Shaft rotation rudder deflection , The rotation angle of the control surface around the control axis is defined as follows: downward deflection of the trailing edge is positive, corresponding to the rotation matrix. for:

[0018] After rotation rudder surface coordinates in coordinate system and shear stress It becomes:

[0019] Select a node on the plane as a partition node:

[0020] In the formula, The coordinate vector of the partition node. The total number of nodes; No. A partition is an arbitrary polygonal region enclosed by boundary nodes, and the boundary nodes are arranged in clockwise or counterclockwise order as follows:

[0021] In the formula, For partition node numbering, This represents the total number of nodes in the partition. After rotation Defining partitions on a plane allows different control surfaces of a set of rudders to use the same partition settings.

[0022] Preferably, step 5 specifically comprises: After rotating the rudder surface in step 4, determine the partition to which each grid cell on the rudder surface belongs; Area of ​​the polygon enclosed by the partition boundary nodes for:

[0023] In the formula, when j=N i hour, ; For the first Partition number Boundary point coordinate components, For the first Boundary point coordinate components; Cell center of a certain grid With the The area enclosed by the partition boundary nodes is:

[0024] If the following conditions are met:

[0025] Then this grid cell belongs to the first... Partitioning, in the formula This is the error limit; the load of this mesh element is accumulated to the [number]th [cell]. Partitioning, i.e.:

[0026] In the formula, The first The original resultant force and resultant moment vector on the partition, These are the summation resultant force and resultant moment vector, respectively. The coordinates of the grid cell center and the torque reference point. Take the rudder shaft origin .

[0027] Preferably, the error limit Pick .

[0028] The beneficial effects of this invention are as follows: This invention enables refined acquisition of local aerodynamic loads in key components of spinning-body aircraft, significantly improving the accuracy and reliability of local load environment description. This allows for precise identification of structural weaknesses, guiding optimized design and effectively avoiding design redundancy or inadequacy. The method provides more accurate input loads for structural strength verification, fatigue life prediction, and targeted ground testing, helping to shorten development cycles, reduce verification costs, and ultimately improve the structural safety and mission reliability of the aircraft. Attached Figure Description

[0029] Figure 1 This is a flowchart of the method of the present invention; Figure 2 This is a schematic diagram of the fuselage partitions; Figure 3 A schematic diagram of the rudder (wing) surface partitioning; Figure 4 For example of zoned loads, (1) fuselage, (2) control surfaces. Detailed Implementation

[0030] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0031] The purpose of this invention is to provide a method for extracting aerodynamic loads in a zonal region of a rotating aircraft component. This method first calculates the surface pressure and viscous shear force of the entire aircraft using computational fluid dynamics (CFD) software, and then obtains the aerodynamic loads in a specified region by integration based on a zonal method.

[0032] Step 1: Calculate the surface pressure and shear stress of the entire machine; Based on the full-scale 3D digital model, complex local details with minimal aerodynamic impact are refined to obtain a concise and complete aerodynamic shape. The processed shape file is then imported into mesh generation software, with the coordinate system set to the origin. Located at the nose, The shaft points from the head to the tail of the machine. Axis perpendicular The axis lies in the normal plane. Axis perpendicular to For the planar model, first mesh the entire aircraft surface, then generate a spatial volume mesh. In the boundary settings, define the fuselage, rudder / wing, and other components separately. Import the mesh file into the CFD software, set the incoming flow conditions and boundary conditions, initialize the flow field, and start the calculation. After completion, output the coordinates, pressure, and shear stress results of the entire aircraft surface.

[0033] Step 2: Method for defining fuselage partitions; The fuselage of a spin-type aircraft is spin-type, and the entire fuselage is divided into sections along both the axial and radial directions, such as... Figure 2 As shown, the dividing points for the axial and radial directions are:

[0034] In the formula, partition The area is:

[0035] Step 3: Computer body partition aerodynamic load; Based on the total aircraft surface coordinates exported in the first step, determine the partition to which each grid cell on the fuselage surface belongs. (Grid cell center coordinates) The calculation is as follows:

[0036] Radial angle corresponding to the center of the grid cell for:

[0037] If the following conditions are met:

[0038] Then this grid cell belongs to the first... The corresponding local aerodynamic forces are accumulated in that partition, i.e.:

[0039] In the formula, These are the coordinates of the torque reference point, typically taken at the machine head position.

[0040] Step 4: Method for defining rudder (wing) surface zones; Before partitioning, first move the rudder plane from the global coordinate system. Transform to the local coordinate system Among them, the origin It is the intersection of the rudder shaft centerline and the rudder root chord plane. From the leading edge of the rudder root string to the trailing edge Pointing towards the rudder tip along the centerline of the rudder shaft, According to the right-hand rule, perpendicular to Plane. First, translate the origin of the global coordinate system to... Then, after the following three rotations; The first time, around Axis rotation azimuth angle (rudder shaft and) The angle between the planes (positive when viewed from back to front, counterclockwise) corresponds to the rotation matrix. for:

[0041] After rotation rudder surface coordinates in coordinate system and shear stress It becomes:

[0042] In the formula, for Coordinate vectors in a coordinate system The origin of the control surface coordinate.

[0043] The second time, Coordinate system around Axis-reverse rotation of the control surface sweep angle (The angle between the rudder axis and the fuselage cross-section is positive when it is biased towards the tail), corresponding to the rotation matrix. for:

[0044] After rotation rudder surface coordinates in coordinate system and shear stress It becomes:

[0045] The third time, Coordinate system around Shaft rotation rudder deflection (The rotation angle of the control surface around the control axis, with the trailing edge deflected downwards as positive), corresponding to the rotation matrix. for:

[0046] After rotation rudder surface coordinates in coordinate system and shear stress It becomes:

[0047] The next steps are in Implemented in a coordinate system.

[0048] The partitioning of the control surface is defined using a concept similar to that of unstructured grids. For example... Figure 3 As shown, Select a node on the plane as a partition node:

[0049] No. A partition is an arbitrary polygonal region enclosed by boundary nodes, and the boundary nodes are arranged in clockwise or counterclockwise order as follows:

[0050] After rotation Defining partitions on a plane allows different control surfaces of a set of rudders to use the same partition settings.

[0051] Step 5: Calculate the aerodynamic loads of the rudder (wing) surface zones; After rotating the rudder surface in step four, determine the partition to which each grid cell on the rudder surface belongs. Area of ​​the polygon enclosed by the partition boundary nodes for:

[0052] Cell center of a certain grid With the The area enclosed by the partition boundary nodes is:

[0053] If the following conditions are met:

[0054] Then this grid cell belongs to the first... Partitioning, in the formula It is a human-given error limit, generally taken as... The aerodynamic force of this unit is accumulated in this partition, that is:

[0055] Using the above method, the zoned load extraction of the fuselage and tail rudder of the tail-rudder type spin-type aircraft was carried out. The fuselage was divided into 20 equal sections along the axial direction, 4 equal sections radially (corresponding to quadrants 1 to 4), 4 equal sections spanwise (from root to tip, corresponding to spanwise 1 to 4), and 6 equal sections chordally. Figure 4 The results show that the aerodynamic loads in different zones are significantly different, so it is essential to extract the aerodynamic load zones when designing a structure in a refined manner.

Claims

1. A method for extracting aerodynamic loads from partitions of a rotating aircraft component, characterized in that, Includes the following steps: Step 1: Calculate the surface pressure and shear stress of the entire machine; Step 2: Define the chassis partitions; Step 3: Computer body section aerodynamic load; Step 4: Define the control surface partitions; Step 5: Calculate the aerodynamic loads of the control surface zones.

2. The method for extracting aerodynamic loads from the partitions of a rotating aircraft component according to claim 1, characterized in that, Step 1 specifically involves: Based on the full-scale 3D digital model of the aircraft, a complete aerodynamic shape was obtained; the processed shape file was then imported into mesh generation software, with the coordinate system set to the origin. Located at the nose, The shaft points from the head to the tail of the machine. Axis perpendicular The axis lies in the normal plane. Axis perpendicular to For the plane, first divide the entire aircraft surface into meshes, then generate the spatial volume mesh, and define the fuselage and rudder / wing components separately in the boundary settings; Import the mesh file into the CFD software, set the incoming flow conditions and boundary conditions, initialize the flow field, and start the calculation. After completion, output the coordinates, pressure, and shear stress results of the entire machine surface.

3. The method for extracting aerodynamic loads from partitions of a rotating aircraft component according to claim 2, characterized in that, Step 2 specifically involves: The fuselage of the spin-type aircraft is a spin-type body, and the entire fuselage is divided into sections along both the axial and radial directions. The dividing points for the axial and radial directions are: In the formula, For the first Axial division points coordinate, For the first Angle at each radial dividing point, from Starting from the positive direction, rotating counterclockwise is considered positive. These represent the number of segments in the axial and radial directions, respectively. partition The area is: 。 4. The method for extracting aerodynamic loads from the partitions of a rotating aircraft component according to claim 3, characterized in that, Step 3 specifically involves: Based on the full-scale surface coordinates exported in step 1, determine the partition to which each grid cell on the fuselage surface belongs; Grid cell center coordinates The calculation is as follows: In the formula, This represents the total number of nodes in the grid cell; , , These are the coordinate components of the grid cell nodes; Radial angle corresponding to the center of the grid cell for: If the following conditions are met: Then this grid cell belongs to the first... The corresponding local aerodynamic forces are accumulated in that partition, i.e.: In the formula, They are the first The original resultant force and resultant moment vector on the partition, These are the summation resultant force and resultant moment vector, respectively. It is the pressure at the center of the unit. It is a unit area vector. It is the shear stress vector. These are the coordinates of the torque reference point.

5. The method for extracting aerodynamic loads from partitions of a rotating aircraft component according to claim 4, characterized in that, Step 4 specifically involves: Before partitioning, first move the rudder plane from the global coordinate system. Transform to the local coordinate system Among them, the origin It is the intersection of the rudder shaft centerline and the rudder root chord plane. From the leading edge of the rudder root string to the trailing edge Pointing towards the rudder tip along the centerline of the rudder shaft, According to the right-hand rule, perpendicular to flat; Translate the origin of the global coordinate system to Then, after the following three rotations: The first time, around Axis rotation azimuth angle , For the rudder shaft and The angle between planes, viewed from back to front, is positive counterclockwise, corresponding to the rotation matrix. for: After rotation rudder surface coordinates in coordinate system and shear stress It becomes: In the formula, for Coordinate vectors in a coordinate system The origin of the control surface coordinate; The second time, Coordinate system around Axis-reverse rotation of the control surface sweep angle , The angle between the rudder axis and the fuselage cross-section is positive when it is deflected towards the tail, corresponding to the rotation matrix. for: After rotation rudder surface coordinates in coordinate system and shear stress It becomes: The third time, Coordinate system around Shaft rotation rudder deflection , The rotation angle of the control surface around the control axis is defined as follows: downward deflection of the trailing edge is positive, corresponding to the rotation matrix. for: After rotation rudder surface coordinates in coordinate system and shear stress It becomes: Select a node on the plane as a partition node: In the formula, The coordinate vector of the partition node. The total number of nodes; No. A partition is an arbitrary polygonal region enclosed by boundary nodes, and the boundary nodes are arranged in clockwise or counterclockwise order as follows: In the formula, For partition node numbering, This represents the total number of nodes in the partition. After rotation Defining partitions on a plane allows different control surfaces of a set of rudders to use the same partition settings.

6. The method for extracting aerodynamic loads from partitions of a rotating aircraft component according to claim 5, characterized in that, Step 5 specifically involves: After rotating the rudder surface in step 4, determine the partition to which each grid cell on the rudder surface belongs; Area of ​​the polygon enclosed by the partition boundary nodes for: In the formula, when j=N i hour, ; For the first Partition number Boundary point coordinate components, For the first Boundary point coordinate components; Cell center of a certain grid With the The area enclosed by the partition boundary nodes is: If the following conditions are met: Then this grid cell belongs to the first... Partitioning, in the formula This is the error limit; the load of this mesh element is accumulated to the [number]th [cell]. Partitioning, i.e.: In the formula, The first The original resultant force and resultant moment vector on the partition, These are the summation resultant force and resultant moment vector, respectively. The coordinates of the grid cell center and the torque reference point. Take the rudder shaft origin .

7. The method for extracting aerodynamic loads from the partitions of a rotating aircraft component according to claim 6, characterized in that, The error limit Pick .

8. An electronic device, characterized in that, include: Processor and memory; The memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory to cause the electronic device to perform the method as described in any one of claims 1 to 7.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the method as described in any one of claims 1 to 7.

10. A chip, characterized in that, include: A processor for retrieving and running a computer program from memory, causing a device on which the chip is mounted to perform the method as described in any one of claims 1 to 7.

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