Aircraft wall ablation response data processing method based on interpolation algorithm

Abstract

The application discloses an aircraft wall ablation response data processing method based on an interpolation algorithm and relates to the field of ablation response data processing. The method comprises the following steps: ablation sites are laid out, and initial coordinate information of the ablation sites is output; coordinate information of ablation wall surface grid core points is acquired, and ablation site coordinates after ablation recession are calculated in combination with the initial coordinate information of the ablation sites; ablation information at the ablation sites is acquired, interpolation is performed on the ablation information based on the ablation site coordinates after ablation recession, and ablation information after interpolation is obtained; wall surface mapping is performed on the ablation information after interpolation, and continuous distribution of material ablation response on the entire ablation wall surface is acquired. The method can realize interpolation processing of multiple ablation information in limited scattered ablation sites on a complex ablation surface, and has the advantages of simple algorithm, strong applicability and high calculation efficiency compared with typical two-dimensional or three-dimensional interpolation algorithms.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of ablation response data processing, in particular to an aircraft wall ablation response data processing method based on an interpolation algorithm. BACKGROUND

[0002] Aerodynamic force / thermal environment-material ablation response coupling calculation is a complex coupling calculation involving multi-domain, multi-field and multi-scale. During the reentry flight of the aircraft, due to the strong compression effect of the shock wave and the wall viscosity stagnation effect, the surface of the aircraft is subjected to long-term aerodynamic force / thermal load, which causes the surface material to undergo strong thermo-chemical ablation. On the one hand, the material ablation response includes ablation gas mass injection, ablation shape recession, surface ablation product and ablation temperature distribution, which will change the near-wall flow state and the aircraft aerodynamic shape, and further change the aerodynamic force / thermal environment of the aircraft. On the other hand, the changed aerodynamic force / thermal environment will affect the ablation response of the material. Therefore, in order to simplify the calculation process and improve the coupling calculation efficiency, a loose coupling calculation method based on aerodynamic force thermal environment and material ablation response partition calculation, and bidirectional coupling of aerodynamic force / thermal and material ablation response is often used. In the whole loose coupling calculation process, how to construct the ablation response boundary condition suitable for CFD (Computational Fluid Dynamics) and then introduce the ablation response of the material into the calculation of the aerodynamic force / thermal environment of the aircraft is an important link. The commonly used method is to construct a wall mass injection boundary condition based on the momentum / mass conservation relationship between the ablation wall and the first layer of calculation grid, to use the Fixed boundary condition to represent the wall ablation component distribution, and to use the dynamic grid technology to capture the ablation recession profile and update the calculation grid of the flow field. The establishment of these ablation response boundaries all need to be based on the continuous distribution of the material ablation response information on the whole ablation wall. Since the ablation calculation methods that are relatively mature and widely used at present are mostly one-dimensional calculation methods, i.e. only a single site can be calculated for material ablation response at a time, and considering the efficiency of bidirectional coupling calculation, the number of ablation sites must be limited. Therefore, interpolation algorithm is needed to interpolate the ablation information of the scattered limited sites to obtain the continuous distribution of the wall material ablation response.

[0003] The ablation calculation points arranged on the ablation wall surface of a typical aircraft are usually a limited number of points scattered on a three-dimensional curved surface in a rectangular coordinate space. Since the ablation wall surface varies with the aerodynamic shape of the aircraft and recedes in real time during the ablation process, it is difficult to determine the numerical expression thereof, and therefore continuous distribution of the ablation information of the wall surface cannot be obtained by using traditional two-dimensional or three-dimensional linear interpolation algorithms. Meanwhile, the ablation information of each ablation point that needs to be interpolated includes ablation point coordinates, wall surface mass flow rate, wall surface ablation temperature, wall surface injection velocity, wall surface ablation component mass distribution (including thermal chemical ablation products of multiple carbons and pyrolysis products of multiple phenolic resins), etc. However, the traditional high-dimensional linear interpolation algorithm has significant defects in terms of calculation efficiency, and the time and resources required for interpolation calculation increase sharply with the increase in the number of data points and the amount of interpolation information, which greatly limits the application potential of the interpolation algorithm in the fine interpolation calculation of the ablation information of the wall surface of a large aircraft. SUMMARY

[0004] In view of the above problems in the prior art, the ablation response data processing method for an aircraft wall surface based on an interpolation algorithm provided in the present application solves the problem that the continuous distribution of the ablation information of the wall surface cannot be obtained by using the traditional two-dimensional or three-dimensional linear interpolation algorithm.

[0005] To achieve the above-mentioned purposes, the technical scheme adopted by the present application is as follows:

[0006] The present application provides an ablation response data processing method for an aircraft wall surface based on an interpolation algorithm, which comprises the following steps:

[0007] The ablation points are arranged, and the initial coordinate information of the ablation points is outputted;

[0008] The coordinate information of the grid center points of the ablation wall surface is obtained, and the coordinate information of the ablation points after the ablation recession is calculated in combination with the initial coordinate information of the ablation points;

[0009] The ablation information at the ablation points is obtained, the ablation information is interpolated based on the coordinate information of the ablation points after the ablation recession, and the interpolated ablation information is obtained;

[0010] The interpolated ablation information is mapped to the wall surface, and the continuous distribution of the material ablation response on the entire ablation wall surface is obtained.

[0011] Further, the specific method for arranging the ablation points comprises:

[0012] For the initial blunt body configuration and typical transition ablation morphology at different times, the grid drawing tool is used to arrange 6 groups of ablation sites in the x coordinate axis direction for the initial blunt body configuration, the ablation morphology at different times when typical transition ablation occurs, wherein the number of ablation sites in the first group is 1, arranged at the vertex position of the blunt body; the number of ablation sites in each of the remaining groups is 6, and the x-axis coordinates of the ablation sites arranged in each group remain the same; after the point arrangement is completed, the coordinate information of the ablation sites is grouped and output to generate an ablation_position.dat file.

[0013] Further, the specific method for obtaining the ablation wall surface grid center point coordinate information includes:

[0014] Read the grid center point position coordinate information ablation_position.dat file generated by the grid drawing software, read the ablation wall surface grid center point coordinates and normal vector information cellcenter_message.dat file given by the aircraft aerodynamic force / thermal environment calculation CFD program, and obtain the ablation wall surface grid center point coordinates and normal vector.

[0015] Further, the specific method for calculating the ablation site coordinate after ablation retreat in combination with the ablation site initial coordinate information includes the following steps:

[0016] According to the principle of minimum Euclidean distance between the ablation wall surface grid center point and the ablation site, based on the formula:

[0017]

[0018] Calculate the Euclidean distance between the current ablation site and all ablation wall surface grid center points ; wherein is the coordinate of any ablation wall surface grid center point; is the coordinate of the current ablation site;

[0019] According to the Euclidean distance between the current ablation site and all ablation wall surface grid center points, determine the ablation wall surface grid center point closest to the current ablation site, and take the normal vector information at the ablation wall surface grid center point as the initial normal vector of the current ablation site;

[0020] Based on the initial normal vector of the current ablation site, calculate the ablation site coordinate after ablation retreat, which is expressed as:

[0021]

[0022] wherein is the ablation site coordinate after ablation retreat; is the initial coordinate of the current ablation site; is the initial normal vector of the current ablation site; This represents the ablation retreat at the current ablation site.

[0023] Output the coordinates of the ablation site after the ablation retreat as a file named new_ablation_position.dat.

[0024] Furthermore, the specific method for obtaining ablation information at the ablation site is as follows:

[0025] Ablation information at the ablation site is obtained by reading the ablation information file ablation_calculation.dat output by the material ablation analysis software.

[0026] Furthermore, specific methods for interpolating ablation information include:

[0027] Interpolation is performed only in the x-direction for the ablation information of the two-dimensional curve; interpolation is then performed in the z-direction and x-direction for the ablation information of the three-dimensional surface.

[0028] Furthermore, the specific method for interpolating the ablation information of the two-dimensional curve only in the x-direction includes the following steps:

[0029] Determine the projection plane and project all the coordinates of the ablation sites after ablation retreat onto the xz plane; assign the ablation information at the ablation site to the corresponding ablation site after ablation retreat.

[0030] Determine the number of interpolation points between two adjacent ablation retreat sites within the same group and perform linear interpolation of the ablation information; that is, according to the formula or A linear interpolation of ablation information is performed sequentially along the x-direction between two adjacent ablation retreat sites within the group; where... This is the result of a linear interpolation. and These are the ablation information of two adjacent ablation retreat sites within the group; and It is a linear interpolation factor;

[0031] Output the interpolation results of the ablation sites in the projection plane after ablation and generate the interpolation_ablation_message.dat file to obtain the ablation information of each interpolation point, that is, the ablation information after two-dimensional curve interpolation.

[0032] Furthermore, the specific method for interpolating the three-dimensional surface ablation information sequentially in the z and x directions includes the following steps:

[0033] Determine the projection plane and project all the coordinates of the ablation sites after ablation retreat onto the xz plane; assign the ablation information at the ablation site to the corresponding ablation site after ablation retreat.

[0034] Determine the number of groups, the number of ablation retreat sites in the same group, the number of interpolations between two adjacent ablation retreat sites in the x-direction, and the number of interpolations between two adjacent ablation retreat sites in the z-direction.

[0035] The ablation information of the ablation retreat and ablation site group at the end of the aircraft is copied and expanded to be consistent with the number of other ablation retreat and ablation site groups.

[0036] For each group of ablation sites after retreat, a linear interpolation of the ablation information within the group is performed, i.e., according to the formula... or A linear interpolation of ablation information is performed sequentially along the z-direction between two adjacent ablation sites after retreat within each group; where... This is the result of a linear interpolation. and These are the ablation information of two adjacent ablation retreat sites within the group; and It is a linear interpolation factor;

[0037] Along the x-direction, after a linear interpolation, a second interpolation of the ablation information is performed between the corresponding ablation sites in the adjacent two groups of ablation sites. The interpolation results of the ablation sites in the projection plane are output and the interpolation_ablation_message.dat file is generated to obtain the ablation information of each interpolation point, that is, the ablation information after three-dimensional surface interpolation.

[0038] Furthermore, , Pi , The coordinates of the current point to be interpolated along the interpolation direction; The coordinates of the first ablation retreat ablation site among two adjacent ablation retreat ablation sites; The coordinates are the coordinates of the second ablation retreat ablation site among two adjacent ablation retreat ablation sites.

[0039] Furthermore, specific methods for wall mapping of the interpolated ablation information include:

[0040] The coordinates of the grid center points of the ablation surface after retreat are obtained through the RBF dynamic meshing program for ablation surface retreat. The Euclidean distance between the interpolation point and each grid center point of the ablation surface after retreat is calculated. The grid center point of the ablation surface after retreat with the minimum Euclidean distance to the current interpolation point is found. The ablation information of the current interpolation point is assigned to the grid center point of the ablation surface after retreat, thus completing the wall mapping of the interpolated ablation information and outputting it as the ablation_BC.dat file.

[0041] The beneficial effects of this invention are as follows:

[0042] (1) This method can realize the interpolation processing of the ablation site information scattered on the ablation surface during the ablation retreat of complex aircraft through four processes: ablation site layout, ablation site coordinate calculation after ablation retreat, ablation information interpolation, and interpolation information wall mapping. This method can obtain the continuous distribution of material ablation response on the entire ablation surface, further expand the application of one-dimensional material ablation response program in ablation calculation of complex-shaped aircraft, and also provide a new coupling scheme for the aerodynamic / thermal environment-material ablation coupled calculation method of aircraft.

[0043] (2) This method is suitable for interpolation processing of ablation site data in full-model or half-model aerodynamic / thermal-material ablation coupling calculation of various two-dimensional or three-dimensional complex aircraft configurations; it is suitable for interpolation of ablation site data when there is no ablation retreat or small ablation retreat on the aircraft surface during short-term ablation, and it is also suitable for interpolation of ablation site data when there is large ablation retreat on the aircraft surface during long-term severe ablation.

[0044] (3) This method is suitable for interpolation processing of ablation site data for complex-shaped aircraft, including laminar ablation, transition ablation and turbulent ablation. At the same time, this method has no restrictions on the ablation thermal protection materials used in the aircraft and can be adapted to the interpolation processing of ablation response information of various thermal protection materials such as carbon-based materials, silicon-based materials, resin materials and ceramic-based materials.

[0045] (4) This method can handle interpolation processing of various ablation information, including ablation site coordinates (x,y or x,y,z), wall mass flow rate, wall ablation temperature, wall ejection velocity, mass fraction of typical fiber thermochemical ablation components (taking carbon fiber as an example: O, O2, N, N2, CO, CO2, CN, C2N, C, C2, C3, C4, C5, NO) and mass fraction of typical matrix pyrolysis components (taking phenolic resin as an example: H2O, C6H6, C6H5OH, CH4, H2).

[0046] (5) In the process of interpolating the ablation information of the ablation sites after ablation, this method performs one-dimensional linear interpolation between adjacent ablation sites within a group and between corresponding ablation sites in two adjacent groups, both along the arrangement direction of the ablation sites within the group and perpendicular to the arrangement direction of the ablation sites within the group. By combining the grouping and layout scheme of the ablation sites and the two successive one-dimensional linear interpolations of the ablation site information in the two directions and the wall mapping of the interpolated information, this method can realize the interpolation processing of multiple ablation information in a finitely scattered ablation sites on a complex ablation surface. Compared with typical two-dimensional or three-dimensional interpolation algorithms, it has the advantages of simple algorithm, strong applicability and high computational efficiency. Attached Figure Description

[0047] Figure 1 This is a flowchart illustrating the method.

[0048] Figure 2 A schematic diagram of the linear interpolation process for ablation information;

[0049] Figure 3 The images show the initial blunt-nosed body configuration and typical transitional ablation morphology at different times; where (a) is the initial blunt-nosed body configuration, (b) is the typical transitional ablation morphology at time t1, and (c) is the typical transitional ablation morphology at time t2.

[0050] Figure 4 Generatrixes representing the initial blunt-nosed body configuration and typical transitional ablation morphologies at different times;

[0051] Figure 5 The results of heat flux calculation and interpolation for the initial blunt-nosed body configuration are compared; (a) is the calculated wall heat flux cloud map, (b) is the interpolated wall heat flux cloud map, (c) is the calculated wall heat flux data along the centerline, and (d) is the interpolated wall heat flux data along the centerline.

[0052] Figure 6 The results show the convergence of the aerodynamic / thermal environment-material ablation coupling calculation for typical transitional ablation morphology at different times, where (a) is the data at time t1 and (b) is the data at time t2. Detailed Implementation

[0053] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0054] like Figure 1 As shown, the method for processing aircraft wall ablation response data based on interpolation algorithms includes the following steps:

[0055] S1. Deploy ablation sites and output the initial coordinate information of the ablation sites;

[0056] S2. Obtain the coordinate information of the grid center point of the ablation wall surface, and calculate the coordinates of the ablation site after the ablation retreat by combining the initial coordinate information of the ablation site.

[0057] S3. Obtain ablation information at the ablation site, and interpolate the ablation information based on the coordinates of the ablation site after ablation retreat to obtain the interpolated ablation information.

[0058] S4. Perform wall mapping on the interpolated ablation information to obtain the continuous distribution of the material ablation response across the entire ablation wall.

[0059] During the placement of ablation sites, groups of ablation sites are set up along the maximum length direction of the ablation wall of the aircraft (e.g., the x-axis direction). The coordinates of each group of ablation sites remain constant along the maximum length direction of the ablation wall and are evenly distributed circumferentially. The number of ablation sites in each group remains consistent. If the ablation wall covers the apex of the aircraft's nose, only one ablation site needs to be placed at the apex. In areas of intense ablation, such as near the apex of a blunt-nosed body, the distance between adjacent groups of ablation sites is appropriately reduced to better capture the rapidly changing aerodynamic / thermal environment and thus better characterize the changes in the corresponding material ablation response. The spacing between ablation sites within different groups remains relatively consistent. However, in areas of intense ablation, such as the windward side of the aircraft, the number of ablation sites can be appropriately increased, and the distance between adjacent ablation sites can be reduced.

[0060] In this embodiment, the specific method for setting up ablation sites in step S1 includes:

[0061] like Figure 3 and Figure 4 As shown, for the initial blunt-nosed body configuration and typical transitional ablation morphologies at different times, six groups of ablation sites were arranged along the x-axis direction for the initial blunt-nosed body configuration and the ablation morphologies at different times during typical transitional ablation using mesh drawing tools such as pointwise. The first group had one ablation site, located at the vertex of the blunt-nosed body; the remaining groups each had six ablation sites, and the x-axis coordinates of the ablation sites within each group were kept consistent. After the points were arranged, the coordinate information of the ablation sites was output in groups, generating the ablation_position.dat file.

[0062] In this embodiment, the specific method for obtaining the coordinate information of the grid center point of the ablated wall mesh in step S2 includes: reading the grid center point position coordinate information ablation_position.dat file generated by mesh drawing software such as pointwise, and reading the grid center point coordinate and normal vector information cellcenter_message.dat file given by the aircraft aerodynamic / thermal environment calculation CFD program to obtain the grid center point coordinate and normal vector of the ablated wall mesh.

[0063] In this embodiment, the specific method for calculating the coordinates of the ablation site after retreat in step S2, based on the initial coordinate information of the ablation site, includes the following steps:

[0064] S2-1. Based on the principle of minimizing the Euclidean distance between the grid center and the ablation site on the ablation wall, and using the formula:

[0065]

[0066] Calculate the Euclidean distance between the current ablation site and the center points of all ablation wall grids. ;in The coordinates of the center point of any ablation wall grid; The coordinates of the current ablation site;

[0067] S2-2. Based on the Euclidean distance between the current ablation site and the center points of all ablation wall grids, determine the center point of the ablation wall grid that is closest to the current ablation site, and use the normal vector information at the center point of the ablation wall grid as the normal vector at the current ablation site.

[0068] S2-3. Based on the normal vector at the current ablation site, calculate the coordinates of the ablation site after the ablation retreat. The expression is as follows:

[0069]

[0070] in The coordinates of the ablation site after the ablation retreat; The initial coordinates of the current ablation site; This is the initial normal vector for the current ablation site; This represents the ablation retreat at the current ablation site.

[0071] S2-4. Output the coordinates of the ablation site after the ablation retreat as a file named new_ablation_position.dat.

[0072] In step S3, the specific method for obtaining ablation information at the ablation site is as follows: the ablation information at the ablation site is obtained by reading the ablation information file ablation_calculation.dat output by the material ablation analysis software.

[0073] In this embodiment, as Figure 2 As shown, the specific method for interpolating the ablation information in step S3 includes: interpolating the two-dimensional curve ablation information only in the x direction; and interpolating the three-dimensional surface ablation information in the z and x directions in turn.

[0074] In the specific implementation process, the method for interpolating the two-dimensional curve ablation information only in the x-direction includes the following steps:

[0075] A1. Determine the projection plane and project all the coordinates of the ablation sites after the ablation retreats onto the xz plane to ensure that the ablation sites are not overlapping in the projection plane; assign the ablation information at the ablation site to the corresponding ablation site after the ablation retreats.

[0076] A2. Determine the number of interpolation points between two adjacent ablation retreat sites within the same group and perform linear interpolation of the ablation information; that is, according to the formula... or A linear interpolation of ablation information is performed sequentially along the x-direction between two adjacent ablation retreat sites within the group; where... This is the result of a linear interpolation. and These are the ablation information of two adjacent ablation retreat sites within the group; and It is a linear interpolation factor;

[0077] A3. Output the interpolation results of the ablation sites in the projection plane after ablation and generate the interpolation_ablation_message.dat file to obtain the ablation information of each interpolation point, that is, the ablation information after two-dimensional curve interpolation.

[0078] In the specific implementation process, the method for interpolating the three-dimensional surface ablation information sequentially in the z and x directions includes the following steps:

[0079] B1. Determine the projection plane and project all the coordinates of the ablation sites after the ablation retreat into the xz plane to ensure that the ablation sites are not overlapping in the projection plane; assign the ablation information at the ablation site to the corresponding ablation site after the ablation retreat.

[0080] B2. Determine the number of groups, the number of ablation retreat sites in the same group, the number of interpolations between two adjacent ablation retreat sites in the x direction, and the number of interpolations between two adjacent ablation retreat sites in the z direction.

[0081] B3. Copy and expand the ablation information of the ablation retreat and ablation site group at the end point of the aircraft (i.e. the apex of the blunt body) to be consistent with the number of other ablation retreat and ablation site groups (6).

[0082] B4. Perform linear interpolation of the ablation information within each group for the ablation sites after retreat, i.e., according to the formula... or A linear interpolation of ablation information is performed sequentially along the z-direction between two adjacent ablation sites after retreat within each group; where... This is the result of a linear interpolation. and These are the ablation information of two adjacent ablation retreat sites within the group; and It is a linear interpolation factor;

[0083] B5. Along the x-direction, sequentially perform secondary interpolation of the ablation information between the corresponding ablation sites in the two adjacent groups after linear interpolation, output the interpolation results of the ablation sites in the projection plane and generate the interpolation_ablation_message.dat file to obtain the ablation information of each interpolation point, that is, the ablation information after three-dimensional surface interpolation.

[0084] In this embodiment, , Pi , The coordinates of the current point to be interpolated along the interpolation direction; The coordinates of the first ablation retreat ablation site among two adjacent ablation retreat ablation sites; The coordinates are the coordinates of the second ablation retreat ablation site among two adjacent ablation retreat ablation sites.

[0085] As can be seen from the above process, in the ablation information interpolation process, it is first necessary to project the coordinates of the ablation sites after ablation onto the plane containing the maximum length direction of the ablation wall of the aircraft, ensuring that the ablation sites after ablation are not overlapping in the projection plane. When interpolating the ablation site information, firstly, intra-group interpolation is performed, that is, one-dimensional linear interpolation of the ablation information is performed sequentially along a certain direction between two adjacent ablation sites within a group. After the interpolation in this direction is completed, a second interpolation of the ablation information is performed sequentially along another direction perpendicular to it between corresponding sites in two adjacent groups after the first interpolation. Finally, the interpolation results of the ablation sites in the projection plane are output. It should be noted that if the aircraft calculation model is a full model, it is necessary to divide the aircraft into upper and lower parts along the projection plane, and sequentially project the ablation sites of each part onto the projection plane for interpolation calculation. When interpolating the ablation information between two adjacent ablation sites, different linear interpolation algorithms can be selected to better represent the distribution of ablation information.

[0086] In this embodiment, the wall mapping of the interpolated ablation information is performed last. The interpolated information of the ablation points in the projection plane is projected onto the ablation wall of the aircraft using the criterion of minimum Euclidean distance between the interpolation point and the center point of the ablation surface grid after ablation retreat. In this process, for each interpolation point, the center points of the ablation surface grid after ablation retreat are traversed sequentially, the Euclidean distance between the current interpolation point and each center point of the ablation surface grid after ablation retreat is calculated, and the center point of the ablation surface grid after ablation retreat with the current interpolation point is found. The ablation information of the current interpolation point is assigned to this grid point and output as ablation_BC.dat.

[0087] Figure 5 The figure shows a comparison of the calculation and interpolation results of the initial blunt-nosed body configuration heat flux data. As can be seen from the figure, this method can effectively achieve wall interpolation of aerodynamic / ablation response physical information such as heat flux of the ablation wall. It can obtain the continuous distribution of the ablation response of the wall material by interpolation processing based on the ablation information of a limited number of sites. Figure 6 The iterative convergence of the coupled aerodynamic / thermal environment-material ablation calculation for typical transition ablation morphologies at different time points reveals that this method can achieve coupled calculation of the aerodynamic / thermal environment-material ablation response of complex-shaped aircraft. Furthermore, after three rounds of coupled iterations, the surface heat flux of typical transition ablation morphologies at each time point achieves good convergence. This indicates that the method meets the requirements for engineering applications.

[0088] In practical implementation, this method can be applied to the coupled calculation of aerodynamic / thermal environment and material ablation response of complex-shaped aircraft. Complex-shaped aircraft include two-dimensional and three-dimensional configurations. The wall ablation response data includes, but is not limited to, typical carbon-carbon material surface thermochemical ablation data: ablation site coordinates (x,y or x,y,z), wall mass flow rate, wall ablation temperature, wall ejection velocity, and mass fraction of carbothermal ablation components (O, O2, N, N2, CO, CO2, CN, ...). Volumetric ablation data for C2N, C, C2, C3, C4, C5, NO) and typical carbon phenolic materials: ablation site coordinates (x, y or x, y, z), wall mass flow rate, wall ablation temperature, wall ejection velocity, mass fraction of carbothermal ablation components (O, O2, N, N2, CO, CO2, CN, C2N, C, C2, C3, C4, C5, NO) and mass fraction of phenolic pyrolysis components (H2O, C6H6, C6H5OH, CH4, H2).

Claims

1. A method for processing aircraft wall ablation response data based on interpolation algorithm, characterized in that, Includes the following steps: Determine the ablation sites and output the initial coordinate information of the ablation sites; Obtain the coordinate information of the grid center point of the ablation wall surface, and calculate the coordinates of the ablation site after the ablation retreat by combining the initial coordinate information of the ablation site. Obtain ablation information at the ablation site, and interpolate the ablation information based on the coordinates of the ablation site after ablation retreat to obtain the interpolated ablation information. The interpolated ablation information is mapped to the wall surface to obtain the continuous distribution of the material ablation response across the entire ablation wall surface; Specific methods for interpolating ablation information include: Interpolation is performed only in the x-direction for the ablation information of the two-dimensional curve; interpolation is then performed sequentially in the z-direction and x-direction for the ablation information of the three-dimensional surface. The specific method for interpolating the ablation information of a two-dimensional curve only in the x-direction includes the following steps: Determine the projection plane and project all the coordinates of the ablation sites after ablation retreat onto the xz plane; assign the ablation information at the ablation site to the corresponding ablation site after ablation retreat. Determine the number of interpolation points between two adjacent ablation retreat sites within the same group and perform linear interpolation of the ablation information; that is, according to the formula or A linear interpolation of ablation information is performed sequentially along the x-direction between two adjacent ablation retreat sites within the group; where... This is the result of a linear interpolation. and These are the ablation information of two adjacent ablation retreat sites within the group; and It is a linear interpolation factor; Output the interpolation results of the ablation sites in the projection plane after ablation and generate the interpolation_ablation_message.dat file to obtain the ablation information of each interpolation point, that is, the ablation information after two-dimensional curve interpolation; The specific method for interpolating the ablation information of a three-dimensional surface in the z and x directions sequentially includes the following steps: Determine the projection plane and project all the coordinates of the ablation sites after ablation retreat onto the xz plane; assign the ablation information at the ablation site to the corresponding ablation site after ablation retreat. Determine the number of groups, the number of ablation retreat sites in the same group, the number of interpolations between two adjacent ablation retreat sites in the x-direction, and the number of interpolations between two adjacent ablation retreat sites in the z-direction. The ablation information of the ablation retreat and ablation site group at the end of the aircraft is copied and expanded to be consistent with the number of other ablation retreat and ablation site groups. For each group of ablation sites after retreat, a linear interpolation of the ablation information within the group is performed, i.e., according to the formula... or A linear interpolation of ablation information is performed sequentially along the z-direction between two adjacent ablation retreat sites within each group. Along the x-direction, after a linear interpolation, a second interpolation of the ablation information is performed between the corresponding ablation sites in the adjacent two groups of ablation sites. The interpolation results of the ablation sites in the projection plane are output and the interpolation_ablation_message.dat file is generated to obtain the ablation information of each interpolation point, that is, the ablation information after three-dimensional surface interpolation.

2. The method for processing aircraft wall ablation response data based on interpolation algorithm according to claim 1, characterized in that, Specific methods for setting up ablation sites include: For the initial blunt-nosed body configuration and typical transition ablation morphologies at different times, a mesh drawing tool was used to arrange six groups of ablation sites along the x-axis for the initial blunt-nosed body configuration and the ablation morphologies at different times during typical transition ablation. The first group had one ablation site, located at the apex of the blunt-nosed body; the remaining groups each had six ablation sites, and the x-axis coordinates of the ablation sites within each group were kept consistent. After the points were arranged, the coordinate information of the ablation sites was output in groups, generating the ablation_position.dat file.

3. The method for processing aircraft wall ablation response data based on interpolation algorithm according to claim 1, characterized in that, Specific methods for obtaining the coordinate information of the grid center points of the ablated wall surface include: Read the grid center point position coordinate information ablation_position.dat file generated by the mesh drawing software, and read the grid center point coordinates and normal vector information cellcenter_message.dat file given by the ablation wall mesh CFD program for calculating the ablation environment, to obtain the grid center point coordinates and normal vector of the ablation wall mesh.

4. The method for processing aircraft wall ablation response data based on interpolation algorithm according to claim 1, characterized in that, The specific method for calculating the coordinates of the ablation site after retreat, based on the initial coordinate information of the ablation site, includes the following steps: Based on the principle of minimizing the Euclidean distance between the grid center and the ablation site on the ablation wall, and using the formula: Calculate the Euclidean distance between the current ablation site and the center points of all ablation wall grids. ;in The coordinates of the center point of any ablation wall grid; The coordinates of the current ablation site; Based on the Euclidean distance between the current ablation site and the center points of all ablation wall grids, determine the center point of the ablation wall grid that is closest to the current ablation site, and use the normal vector information at the center point of the ablation wall grid as the initial normal vector of the current ablation site. Based on the initial normal vector of the current ablation site, the coordinates of the ablation site after retreat are calculated, and the expression is as follows: in The coordinates of the ablation site after the ablation retreat; The initial coordinates of the current ablation site; This is the initial normal vector for the current ablation site; This represents the ablation retreat at the current ablation site. Output the coordinates of the ablation site after the ablation retreat as a file named new_ablation_position.dat.

5. The method for processing aircraft wall ablation response data based on interpolation algorithm according to claim 1, characterized in that, The specific method for obtaining ablation information at the ablation site is as follows: Ablation information at the ablation site is obtained by reading the ablation information file ablation_calculation.dat output by the material ablation analysis software.

6. The method for processing aircraft wall ablation response data based on interpolation algorithm according to claim 1, characterized in that, , Pi , The coordinates of the current point to be interpolated along the interpolation direction; The coordinates of the first ablation retreat ablation site among two adjacent ablation retreat ablation sites; The coordinates are the coordinates of the second ablation retreat ablation site among two adjacent ablation retreat ablation sites.

7. The method for processing aircraft wall ablation response data based on interpolation algorithm according to claim 1, characterized in that, Specific methods for wall mapping of interpolated ablation information include: The coordinates of the grid center points of the ablation surface after retreat are obtained through the RBF dynamic meshing program for ablation surface retreat. The Euclidean distance between the interpolation point and each grid center point of the ablation surface after retreat is calculated. The grid center point of the ablation surface after retreat with the minimum Euclidean distance to the current interpolation point is found. The ablation information of the current interpolation point is assigned to the grid center point of the ablation surface after retreat, thus completing the wall mapping of the interpolated ablation information and outputting it as the ablation_BC.dat file.

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