Aerodynamic interference correction method for revolution body model under elastic deformation effect

Abstract

The invention provides an aerodynamic interference correction method for a revolution body model under the action of elastic deformation, and relates to an aerodynamic interference correction method under the action of elastic deformation based on an aerodynamic load without elastic deformation by taking an elastic deformation amount as an intermediate quantity and correlating a flight parameter with the aerodynamic load with / without elastic deformation to construct the aerodynamic interference correction method under the action of elastic deformation based on the aerodynamic load without elastic deformation. Compared with a traditional CFD simulation method, the method has the advantage that the workload spent on grid generation can be effectively reduced. The method is good in universality, the program is easy to implement, and the method can be effectively applied to rapid prediction of the aerodynamic load of the internal rotation forming body model under the action of elastic deformation in the engineering field.

Description

Technical Field

[0001] This invention relates to the field of CFD technology, and in particular to a method for correcting aerodynamic disturbances in a spin-shaped model with elastic deformation. Background Technology

[0002] The influence of elastic deformation on the aerodynamic disturbances of models is an important topic in the interdisciplinary research of fluid mechanics and solid mechanics. Wind tunnel testing, as a crucial research tool in the aerospace field, directly affects the measurement and prediction of aerodynamic performance due to the geometric accuracy of the model. However, due to external loads (such as pressure changes caused by high-speed flow) or the elastic properties of the material itself, models may undergo minute elastic deformations during testing. Although these deformations are microscopic, they can significantly alter the geometry of the model surface, thereby interfering with the flow characteristics of the surrounding fluid.

[0003] Traditionally, models are assumed to be rigid bodies, and the impact of their deformation on aerodynamic performance is often ignored. In recent years, however, the rapid development of new air defense, anti-missile, and anti-nearsmal weapons has led to increasingly demanding overload limits for aircraft to meet requirements for stable control, high maneuverability, and precision strikes. The effects of elastic deformation under high angle-of-attack scenarios are becoming increasingly apparent, especially in high-speed, supersonic, or high-temperature environments. Furthermore, in certain complex fluid dynamics problems, such as aerodynamic-thermal coupling and turbulence-boundary layer separation, the model's elastic response may further amplify aerodynamic disturbances.

[0004] Under elastic deformation, the surface of a spinning body model deforms around its central axis, causing changes in aerodynamic loads. Since the amount of elastic deformation is related to flight parameters (Mach number, altitude, angle of attack), conventional CFD simulation methods require generating corresponding structural meshes based on elastic deformation models with different flight parameters. This preprocessing mesh generation is extremely labor-intensive, significantly impacting the progress of CFD simulations. Therefore, there is an urgent need for a method that uses the aerodynamic load results from a spinning body model without elastic deformation as a baseline, combined with the amount of elastic deformation, to quickly predict and correct the aerodynamic loads with elastic deformation. Summary of the Invention

[0005] The purpose of this invention is to provide a method for correcting aerodynamic interference in a spinning model under elastic deformation, so as to achieve rapid prediction of aerodynamic loads on the model under elastic deformation in the engineering field.

[0006] This invention provides a method for correcting aerodynamic disturbances in a spinning body model subjected to elastic deformation, comprising the following steps: S1: Based on the original data table of elastic deformation, analyze the relationship between different elastic deformation amounts and aerodynamic disturbance amounts, find the elastic deformation parameters with the highest correlation, and establish an empirical formula between elastic deformation parameters and aerodynamic disturbance amounts by spline curve fitting. S2: Analyze the relationship between the elastic deformation parameter and the flight parameter, construct a new composite parameter, and make the elastic deformation parameter and the composite parameter monotonically change. Establish an empirical formula between the elastic deformation parameter and the composite parameter by spline curve fitting. S3: Using the elastic deformation parameter as an intermediate quantity, and combining the above two empirical formulas, determine the empirical formula for the aerodynamic disturbance quantity and the composite parameter. This formula is the aerodynamic disturbance correction formula that takes into account the effect of elastic deformation.

[0007] Furthermore, in step S2: the flight parameters include Mach number, altitude, and angle of attack. Based on the relationship between the elastic deformation parameter and the changes in Mach number, altitude, and angle of attack, a new composite parameter that can characterize Mach number, altitude, and angle of attack is constructed, such that the elastic deformation parameter and the composite parameter exhibit a monotonic relationship.

[0008] Furthermore, the composite parameter is a composite parameter that can characterize Mach number, altitude, and angle of attack.

[0009] Further, in step S1: select N states from the total state M of the original elastic deformation data table, calculate the flow field when there is elastic deformation and when there is no elastic deformation, and extract the pitching moment coefficient, where: N=n*m*l, n, m, l represent the number of Mach number, height and angle of attack, respectively, and n, m, l≤3.

[0010] Furthermore, the normal elastic average deformation is denoted as g1, the normal elastic maximum deformation is denoted as g2, and the difference in pitching moment coefficient between the cases with and without elastic deformation is denoted as δC. mz δC was analyzed separately. mz With g1 and δC mz Based on the correlation with g2, the normal deformation parameter with higher correlation is selected, and the first empirical formula δC is obtained through data fitting. mz =f(g).

[0011] Furthermore, from the selected N states, keeping the height and angle of attack constant, data fitting diagrams of the normal deformation and axial position of the central axis of the spiral-shaped model under n different Mach numbers were plotted, showing that the normal deformation and Mach number are positively correlated. From the selected N states, keeping the Mach number and angle of attack constant, data fitting diagrams of the normal deformation and axial position of the central axis of the spiral-shaped model under m different heights were plotted, showing that the normal deformation and height are negatively correlated. From the selected N states, keeping the Mach number and height constant, data fitting diagrams of the normal deformation and axial position of the central axis of the spiral-shaped model under l different angles of attack were plotted, showing that the normal deformation and angle of attack are positively correlated.

[0012] Furthermore, the composite flight parameter C is defined. f=q*α, where q is the dynamic pressure and α is the angle of attack in radians. This ensures the normal deformation parameters g and C of the centerline. f There is a positive correlation trend; g and C f The data fitting yielded the second empirical formula g=k(C) f ).

[0013] Furthermore, substituting the second empirical formula into the first empirical formula yields the final aerodynamic disturbance correction formula for the spinning body model under elastic deformation: δC mz = f [k(C f )).

[0014] The technical solution of this invention constructs an aerodynamic disturbance correction method based on elastic deformation under elastic deformation of inelastic deformation loads by using elastic deformation as an intermediate quantity and correlating the correlation between flight parameters and aerodynamic loads with / without elastic deformation. Compared with traditional CFD simulation methods, this method can effectively reduce the workload spent on mesh generation. This method has good versatility and is relatively simple to implement, and can be effectively applied to the rapid prediction of aerodynamic loads on inward-rotating body models under elastic deformation in engineering fields. Attached Figure Description

[0015] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 Flowchart of the aerodynamic interference correction method for a spinning body model under elastic deformation.

[0017] Figure 2 This is a schematic diagram of an exception to the calculation of a solid.

[0018] Figure 3 This is a graph showing the relationship between the normal elastic average deformation g1 and the difference in pitching moment coefficient with / without elasticity.

[0019] Figure 4 This is a graph showing the relationship between the maximum deformation g2 and the difference in pitching moment coefficient with / without elasticity.

[0020] Figure 5 The graph shows the relationship between the normal elastic average deformation g1 and the Mach number Ma.

[0021] Figure 6 This is a graph showing the relationship between the normal elastic average deformation g1 and the height H.

[0022] Figure 7The graph shows the relationship between the normal elastic average deformation g1 and the angle of attack α.

[0023] Figure 8 The normal elastic mean deformation g1 and the composite flight parameter C f Relationship diagram.

[0024] Figure 9 This is a comparison chart of the direct simulation results and the corrected results of the aerodynamic forces with elastic deformation. Detailed Implementation

[0025] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, 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.

[0026] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] like Figure 1 As shown, the present invention provides a method for correcting aerodynamic disturbances in a spinning body model under elastic deformation, comprising the following steps: (1) Select N states (N=n*m*l, n, m, l≤3) from the total state M of the original data table of elastic deformation. n, m, l represent the number of Mach number, height and angle of attack, respectively. Calculate the flow field when there is elastic deformation and when there is no elastic deformation, and extract the pitching moment coefficient. (2) The normal elastic average deformation is denoted as g1, the normal elastic maximum deformation is denoted as g2, and the difference in pitching moment coefficient between the cases with and without elastic deformation is denoted as δC. mz δC was analyzed separately. mz With g1 and δC mz Correlation with g2 was considered, and the normal deformation parameter with higher correlation was selected. The empirical formula δC was obtained through data fitting. mz =f(g), this formula is denoted as ①; (3) From the selected N states, keep the height and angle of attack unchanged, and draw the data fitting diagrams of the normal deformation and axial position of the axis of the spin-forming model under n different Mach numbers. The normal deformation and Mach number show a positive correlation trend. (4) From the selected N states, keep the Mach number and angle of attack constant, and draw the data fitting diagrams of the normal deformation and axial position of the axis of the spin-forming model under m different heights. The normal deformation and height show a negative correlation trend. (5) From the selected N states, keeping the Mach number and height unchanged, draw the data fitting diagrams of the normal deformation and axial position of the axis of the spin-forming model under l different angles of attack. The normal deformation and angle of attack show a positive correlation trend. (6) Combining the conclusions in (3) to (5), define the composite flight parameter C. f =q*α (where q is dynamic pressure and α is the angle of attack in radians), at this time the normal deformation parameters g and C of the central axis can be guaranteed. f It shows a positive correlation trend; (7) Combine g and C in (6) f Data fitting yields the empirical formula g=k(C) f This formula is denoted as ②; (8) Substituting formula ② into formula ① yields the final aerodynamic disturbance correction formula for the spinning body model under elastic deformation, which is in the form of: δC mz = f [k(C f )).

[0029] This invention presents a simulation test of an aerodynamic interference correction method based on elastic deformation along the normal direction for a certain swirling body shape. The calculated shape is as follows: Figure 2 As shown, the selected states include: incoming Mach number Ma=2, 3, 4, altitude H=0km, and angle of attack α=2°, 10°, 24°, 30°. Figures 3-4The normal elastic mean deformation g1 and maximum deformation g2 are given, and the difference δC between them and the pitching moment coefficient with and without elastic deformation is given. mz The relationship diagram shows that g1 and δC mz The correlation is higher, and g1 is more closely related to δC. mz A linear function can be used for approximation, i.e., δC mz =m*g1+n, substituting the data into the fit yields the empirical formula ①: δC mz =-0.003251*g1-0.00275. Figure 5 , Figure 6 and Figure 7 The relationships between the normal deformation g1 and the Mach number Ma, height H, and angle of attack α are given respectively. Figure 8 The normal elastic mean deformation g1 and the composite flight parameter C are given. f The relationship diagram shows that g1 and C f Similarly, a linear function can be used for approximation, i.e., g1 = k * C. f +b, substituting the data into the empirical formula ②, we obtain g1=0.00005372*C. f +0.255. Substituting empirical formula ② into empirical formula ①, we get: δC mz =-0.003251*(0.00005372* C f +0.255) -0.00275. Figure 9 A comparison chart of direct simulation results and corrected results for aerodynamic forces with elastic deformation is presented, covering all states with Ma=2, 3, 4, 5, altitude H=0, 10km, and angle of attack α=2°, 10°, 16°, 24°, 30°. The chart shows that the corrected values ​​generally agree well with the simulation calculations, with a minimum correction deviation of 0.04%, a maximum of 15.38%, and an average of 1.72%.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for correcting aerodynamic disturbances in a spinning body model subjected to elastic deformation, characterized in that, Includes the following steps: S1: Based on the original data table of elastic deformation, analyze the relationship between different elastic deformation amounts and aerodynamic disturbance amounts, find the elastic deformation parameters with the highest correlation, and establish an empirical formula between elastic deformation parameters and aerodynamic disturbance amounts by spline curve fitting. S2: Analyze the relationship between the elastic deformation parameter and the flight parameter, construct a new composite parameter, and make the elastic deformation parameter and the composite parameter monotonically change. Establish an empirical formula between the elastic deformation parameter and the composite parameter by spline curve fitting. S3: Using the elastic deformation parameter as an intermediate quantity, and combining the above two empirical formulas, determine the empirical formula for the aerodynamic disturbance quantity and the composite parameter. This formula is the aerodynamic disturbance correction formula that takes into account the effect of elastic deformation.

2. The method for correcting aerodynamic disturbances in a spinning body model under elastic deformation according to claim 1, characterized in that, In step S2: the flight parameters include Mach number, altitude and angle of attack. Based on the relationship between the elastic deformation parameter and the changes in Mach number, altitude and angle of attack, a new composite parameter that can characterize Mach number, altitude and angle of attack is constructed, so that the elastic deformation parameter and the composite parameter have a monotonic relationship.

3. The method for correcting aerodynamic disturbances in a spinning body model under elastic deformation according to claim 2, characterized in that, The composite parameter is a composite parameter that can characterize Mach number, altitude, and angle of attack.

4. The method for correcting aerodynamic disturbances in a spinning body model under elastic deformation according to claim 1, characterized in that, In step S1: Select N states from the total state M in the original data table of elastic deformation, calculate the flow field when there is elastic deformation and when there is no elastic deformation, and extract the pitching moment coefficient, where: N=n*m*l, n, m, l represent the Mach number, height and angle of attack respectively, and n, m, l are all positive integers ≤3.

5. The method for correcting aerodynamic disturbances in a spinning body model under elastic deformation according to claim 4, characterized in that, Let g1 be the average normal elastic deformation, g2 be the maximum normal elastic deformation, and δC be the difference in pitching moment coefficient between cases with and without elastic deformation. mz δC was analyzed separately. mz With g1 and δC mz Based on the correlation with g2, the normal deformation parameter with higher correlation is selected, and the first empirical formula δC is obtained through data fitting. mz =f(g).

6. The method for correcting aerodynamic disturbances in a spinning body model under elastic deformation according to claim 5, characterized in that, From the selected N states, keeping the height and angle of attack constant, data fitting plots of the normal deformation and axial position of the central axis of the spiral-shaped model under n different Mach numbers are plotted, showing that the normal deformation and Mach number are positively correlated. From the selected N states, keeping the Mach number and angle of attack constant, data fitting plots of the normal deformation and axial position of the central axis of the spiral-shaped model under m different heights are plotted, showing that the normal deformation and height are negatively correlated. From the selected N states, keeping the Mach number and height constant, data fitting plots of the normal deformation and axial position of the central axis of the spiral-shaped model under l different angles of attack are plotted, showing that the normal deformation and angle of attack are positively correlated.

7. The method for correcting aerodynamic disturbances in a spinning body model under elastic deformation according to claim 6, characterized in that, Define composite flight parameters C f =q*α, where q is the dynamic pressure and α is the angle of attack in radians. This ensures the normal deformation parameters g and C of the centerline. f There is a positive correlation trend; g and C f The data fitting yielded the second empirical formula g=k(C) f ).

8. The method for correcting aerodynamic disturbances in a spinning body model under elastic deformation according to claim 7, characterized in that, Substituting the second empirical formula into the first empirical formula yields the final aerodynamic disturbance correction formula for the spinning body model under elastic deformation: δC mz = f [k(C f )).

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