CN-122021391-A - Method for correcting pneumatic interference of rotational model with elastic deformation function

CN122021391ACN 122021391 ACN122021391 ACN 122021391ACN-122021391-A

Abstract

The invention provides a pneumatic disturbance correction method of a rotational molding model with elastic deformation effect, which is constructed based on the elastic deformation effect without elastic deformation pneumatic load by taking the elastic deformation amount as an intermediate amount and correlating the correlation between flight parameters and the elastic deformation pneumatic load. Compared with the traditional CFD simulation method, the method can effectively reduce the workload spent on grid generation. The method has good universality and simpler program implementation, and can be effectively applied to the rapid prediction of the pneumatic load of the internal rotation adult model under the elastic deformation effect in the engineering field.

Inventors

CHEN Jin
LIU YUWEI
WANG XINCHEN
LIU YAOFENG

Assignees

中国航天空气动力技术研究院

Dates

Publication Date: 20260512
Application Date: 20251222

Claims (8)

1. The method for correcting the pneumatic interference of the rotational model with the elastic deformation function is characterized by comprising the following steps of: S1, analyzing the change relation between different elastic deformation amounts and pneumatic disturbance amounts based on an elastic deformation original data table, searching an elastic deformation amount parameter with the highest correlation degree, and establishing an empirical formula between the elastic deformation amount parameter and the pneumatic disturbance amount in a spline curve fitting mode; S2, analyzing the change relation between the elastic deformation parameter and the flight parameter, constructing a new composite parameter, enabling the elastic deformation parameter and the composite parameter to be in monotone change relation, and establishing an empirical formula between the elastic deformation parameter and the composite parameter in a spline curve fitting mode; And S3, determining an empirical formula of the pneumatic disturbance variable and the composite parameter by taking the elastic deformation parameter as an intermediate quantity and combining the two empirical formulas, wherein the formula is a pneumatic disturbance correction formula taking the elastic deformation function into consideration.
2. The method for modifying the aerodynamic disturbance of a rotational model with elastic deformation according to claim 1, wherein in the step S2, the flight parameters include Mach number, altitude and attack angle, and a new composite parameter capable of representing Mach number, altitude and attack angle is constructed according to the variation relation of the elastic deformation parameters and Mach number, altitude and attack angle, so that the elastic deformation parameters and the composite parameter have a monotonic variation relation.
3. The method for modifying the aerodynamic interference of a rotational molding model with elastic deformation according to claim 2, wherein the composite parameter is a composite parameter capable of characterizing mach number, altitude and attack angle.
4. The method for correcting aerodynamic interference of a rotational model with elastic deformation according to claim 1, wherein in step S1, N states are selected from the total state M of an elastic deformation original data table, flow fields with elastic deformation and without elastic deformation are calculated respectively, pitch moment coefficients are extracted, N=n×m×l, N, M, l represent the number of Mach numbers, heights and attack angles respectively, and N, M, l are positive integers less than or equal to 3.
5. The method for correcting aerodynamic interference of a rotational model with elastic deformation according to claim 4, wherein the normal elastic average deformation is denoted as g1, the normal elastic maximum deformation is denoted as g2, the pitch moment coefficient difference with/without elastic deformation is denoted as δc mz , correlations between δc mz and g1 and correlations between δc mz and g2 are analyzed, normal deformation parameters with higher correlation are selected, and a first empirical formula δc mz =f (g) is obtained by data fitting.
6. The method for correcting the pneumatic interference of the spiral-formed body model with the elastic deformation effect according to claim 5 is characterized in that the height and the attack angle are kept unchanged in N selected states, data fitting graphs of normal deformation quantity and axial position of a central axis of the spiral-formed body model under N different attack angles are respectively drawn, the normal deformation quantity and the Mach number are obtained to be positive correlation trends, the Mach number and the attack angle are kept unchanged in N selected states, data fitting graphs of the normal deformation quantity and the axial position of the central axis of the spiral-formed body model under m different heights are respectively drawn, the normal deformation quantity and the height are obtained to be negative correlation trends, and the normal deformation quantity and the attack angle are obtained to be positive correlation trends in the data fitting graphs of the normal deformation quantity and the axial position of the central axis of the spiral-formed body model under l different attack angles are drawn in the N selected states.
7. The method for correcting aerodynamic interference of a rotational model with elastic deformation according to claim 6, wherein a composite flight parameter C f = q x α is defined, wherein q is dynamic pressure, α is an angle of attack of radian system, and wherein normal deformation parameters g and C f of the central axis are guaranteed to be in positive correlation trend, and the second empirical formula g = k (C f ) is obtained by fitting g to C f data.
8. The method for correcting aerodynamic disturbance of a rotating body model with elastic deformation according to claim 7, wherein the second empirical formula is substituted into the first empirical formula to obtain the final aerodynamic disturbance correction formula of the rotating body model with elastic deformation δC mz = f [k(C f .

Description

Method for correcting pneumatic interference of rotational model with elastic deformation function Technical Field The invention relates to the technical field of CFD (computational fluid dynamics), in particular to a method for correcting pneumatic interference of a rotational molding model with elastic deformation. Background The impact of elastic deformation on model aerodynamic interference is an important topic in the cross-over study of fluid mechanics and solid mechanics. The wind tunnel test is used as an important research means in the aerospace field, and the geometric accuracy of the model is directly related to measurement and prediction of aerodynamic performance. However, due to external loads (such as pressure changes caused by high-speed flow) or the elastic properties of the material itself, the model may undergo slight elastic deformation during the test. Such deformations, while microscopic, can significantly alter the geometry of the mold surface, thereby interfering with the flow characteristics of the surrounding fluid. Traditionally, models are assumed to be rigid bodies, the deformation of which has often neglected the effect on the aerodynamic performance. In recent years, novel anti-air-defense reverse guidance, reverse weapons and the like rapidly develop, and in order to meet the requirements of stable control, high maneuver and accurate striking, the overload limit of an aircraft is continuously improved, and the effect of elastic deformation under a high attack angle posture scene is gradually revealed, especially under high-speed, supersonic speed or high-temperature environments. Furthermore, in some complex hydrodynamic problems, such as aerodynamic thermal coupling, turbulence and boundary layer separation scenarios, the elastic response of the model may further amplify aerodynamic interference effects. Under the action of elastic deformation, the rotary model deforms correspondingly around the profile of the central axis, so that the pneumatic load is changed. Because the elastic deformation is related to flight parameters (Mach number, altitude and attack angle), the conventional CFD simulation method needs to generate corresponding structural grids based on elastic deformation models of different flight parameters during simulation, and the workload of preprocessing grid generation is huge, so that the progress of CFD simulation work is greatly influenced. Based on this, there is a need for a correction method for quickly predicting an elastically deformed pneumatic load by combining the elastic deformation amount with the pneumatic load result of the elastically deformed spinodal model as a reference value. Disclosure of Invention The invention aims to provide a method for correcting pneumatic interference of a rotational model with elastic deformation effect, which realizes quick prediction of pneumatic load of the model under the elastic deformation effect in the engineering field. The invention provides a method for correcting pneumatic interference of a rotational molding model with elastic deformation, which comprises the following steps: S1, analyzing the change relation between different elastic deformation amounts and pneumatic disturbance amounts based on an elastic deformation original data table, searching an elastic deformation amount parameter with the highest correlation degree, and establishing an empirical formula between the elastic deformation amount parameter and the pneumatic disturbance amount in a spline curve fitting mode; S2, analyzing the change relation between the elastic deformation parameter and the flight parameter, constructing a new composite parameter, enabling the elastic deformation parameter and the composite parameter to be in monotone change relation, and establishing an empirical formula between the elastic deformation parameter and the composite parameter in a spline curve fitting mode; And S3, determining an empirical formula of the pneumatic disturbance variable and the composite parameter by taking the elastic deformation parameter as an intermediate quantity and combining the two empirical formulas, wherein the formula is a pneumatic disturbance correction formula taking the elastic deformation function into consideration. Further, in step S2, the flight parameters comprise Mach number, altitude and attack angle, and a new composite parameter capable of representing Mach number, altitude and attack angle is constructed according to the change relation of the elastic deformation parameters and Mach number, altitude and attack angle, so that the elastic deformation parameters and the composite parameter have a monotone change relation. Further, the composite parameter is a composite parameter which can characterize Mach number, altitude and attack angle. In step S1, N states are selected from the total state M of the elastic deformation original data table, flow fields with elastic deformation and flow fields without elastic def