Design method of bearing and medium transportation multifunctional integrated structure

Abstract

The invention belongs to the field of functional structure design, and particularly relates to a bearing and medium transportation multifunctional integrated structure design method. The design method comprises the steps that firstly, a frame structure serving as a design object in an aircraft body is selected according to the bearing capacity requirement and the medium transportation function requirement; step 2, extracting a load borne by the frame structure from the full-aircraft load as a mechanical load input, and carrying out configuration optimization design on the frame structure according to a cooling medium flow demand to obtain an optimal configuration of the frame structure; 3, performing size optimization on the frame structure by adopting a parameter optimization design method to obtain an optimal size parameter combination of the frame structure; and fourthly, according to the optimal configuration and the optimal size parameter combination, the adaptive 3D printing technology is adopted for manufacturing the frame structure. On the premise that the medium conveying function is guaranteed, the bearing capacity of the bearing structure is achieved, the number of parts is reduced, the assembling process and time are shortened, redundant structures are reduced, and light weight is achieved.

Description

Technical Field

[0001] The present application belongs to the field of functional structure design, and in particular relates to a design method for a multifunctional integrated structure for load bearing and medium transportation. Background Art

[0002] At present, the load-bearing structure and medium transport pipeline in the aircraft body are completely separated. The medium transport pipeline is connected and fixed to the load-bearing structure through angle pieces, and there is no coupling relationship between the load-bearing structure and the medium transport pipeline. The medium transport pipeline is connected and fixed through angle pieces, and the load-bearing structure needs to be opened, which weakens the load-bearing capacity of the load-bearing structure, and the load-bearing structure needs to be reinforced; the load-bearing structure, medium transport pipeline, angle pieces, fasteners, etc. result in a large number of parts, many assembly processes, and a long assembly time.

[0003] Therefore, it is desired to have a technical solution to overcome or at least alleviate at least one of the above-mentioned defects of the prior art. Summary of the invention

[0004] The purpose of the present application is to provide a design method for a multifunctional integrated structure for load bearing and medium transport, so as to solve at least one problem existing in the prior art.

[0005] The technical solution of this application is:

[0006] A design method for a multifunctional integrated structure for load bearing and medium transport, comprising:

[0007] Step 1: Select the frame structure of the aircraft body as the design object according to the load-bearing capacity requirements and the medium transport function requirements;

[0008] Step 2: extracting the load borne by the frame structure from the whole machine load as a mechanical load input, and performing configuration optimization design on the frame structure according to the cooling medium flow requirement to obtain the optimal configuration of the frame structure;

[0009] Step 3: Optimize the size of the frame structure by using a parameter optimization design method to obtain an optimal size parameter combination of the frame structure;

[0010] Step 4: According to the optimal configuration and the optimal size parameter combination, the frame structure is manufactured using an adapted 3D printing process.

[0011] In at least one embodiment of the present application, in step 1, according to the load-bearing capacity requirements and the medium transport function requirements, the frame structure selected as the design object in the aircraft fuselage is the 15th frame, and the frame structure includes: a frame web, and the frame web has a load-bearing frame front side and a load-bearing frame back side, wherein,

[0012] The front side of the load-bearing frame is provided with a first supply channel, a second supply channel and front side ribs;

[0013] The back side of the load-bearing frame is provided with a first collecting flow channel, a second collecting flow channel and back side ribs.

[0014] In at least one embodiment of the present application, the frame web includes an upper web portion and a lower web portion, and an upper boundary curve of the upper web portion and a lower boundary curve of the lower web portion have different curvatures.

[0015] In at least one embodiment of the present application, the frame web is a left-right symmetrical structure.

[0016] In at least one embodiment of the present application, in step 2, the optimal configuration of the frame structure includes:

[0017] The first supply flow channel, the second supply flow channel, the first collecting flow channel and the second collecting flow channel are all B-spline curve flow channels obtained by topology optimization technology;

[0018] The first supply flow channel and the first collecting flow channel both adopt a one-divided-into-four or four-divided-into-eight structure;

[0019] The front side ribs and the back side ribs are B-spline curve ribs obtained through topology optimization technology.

[0020] In at least one embodiment of the present application, the optimization model for topological optimization of the second supply flow channel is:

[0021]

[0022] Where D is the vector of all design variables, is the design variable vector of the flow channel configuration control point, is the design variable vector of the rib configuration control point, n is the number of ribs, m is the total number of channels and ribs, is the set of all design variables, C mix is the objective function of the optimization model;

[0023] The objective function C of the optimization model mix It consists of two weighted parts, with weighted coefficients a and b respectively. The first half is the calculation formula for the total elastic strain energy of the structure, where v is a test function defined in the design domain, and Γ u is the design domain boundary, and:

[0024]

[0025] The second half is the velocity difference calculation formula for multi-outlet flow channels, where v i is the fluid velocity of the ith flow channel, v ave is the average value of the fluid flow rate in all flow channels;

[0026] H(·) indicates the use of Heaviside function processing, the parameter δ is used to control the degree of regularization, and a minimum positive value α is introduced to ensure the non-singularity of the overall stiffness matrix of the structure. Its expression is:

[0027]

[0028] Among them, φ S (x) is the topological description function of the structure, and the signed distance function is used as the topological description function of the ribs and the flow channel. ε is the second-order linear strain tensor, and f is the strain acting on the Neumann boundary Γ. t The body force on the Neumann boundary Γ t The surface traction on is the Dirichlet boundary Γ u For simplicity, it is assumed to be a zero matrix. is the upper limit of the optimized volume ratio, is the upper limit vector of the design variables, D is the lower limit vector of the design variables, is the fourth-order isotropic elastic tensor of the solid material;

[0029] Fourth-order isotropic elastic tensor of solid material The expression is:

[0030]

[0031] in, and δ are the fourth-order and second-order identity tensors respectively, E is the elastic modulus of the material, and ν is the Poisson's ratio of the material.

[0032] In at least one embodiment of the present application, the optimization model for topological optimization of the second collecting flow channel is:

[0033]

[0034] Where D is the vector of all design variables, is the design variable vector of the flow channel configuration control point, is the design variable vector of the rib configuration control point, n is the number of ribs, m is the total number of channels and ribs, is the set of all design variables, C mix is the objective function of the optimization model;

[0035] The objective function C of the optimization model mixIt consists of two weighted parts, with weighted coefficients a and b respectively. The first half is the calculation formula for the total elastic strain energy of the structure, where v is a test function defined in the design domain, and Γ u is the design domain boundary, and:

[0036]

[0037] The second half is the velocity difference calculation formula for multi-outlet flow channels, where v i is the fluid velocity of the ith flow channel; v ave is the average value of the fluid flow rate in all flow channels;

[0038] H(·) indicates the use of Heaviside function processing, the parameter δ is used to control the degree of regularization, and a minimum positive value α is introduced to ensure the non-singularity of the overall stiffness matrix of the structure. Its expression is:

[0039]

[0040] Among them, φ S (x) is the topological description function of the structure, and the signed distance function is used as the topological description function of the ribs and the flow channel. ε is the second-order linear strain tensor, and f is the strain acting on the Neumann boundary Γ t The body force on the Neumann boundary Γ t The surface traction on is the Dirichlet boundary Γ u For simplicity, it is assumed to be a zero matrix. is the upper limit of the optimized volume ratio, is the upper limit vector of the design variables, D is the lower limit vector of the design variables, is the fourth-order isotropic elastic tensor of the solid material;

[0041] Fourth-order isotropic elastic tensor of solid material The expression is:

[0042]

[0043] in, and δ are the fourth-order and second-order identity tensors respectively, E is the elastic modulus of the material, and ν is the Poisson's ratio of the material.

[0044] In at least one embodiment of the present application, the optimization model for topological optimization of the front ribs and the back ribs is:

[0045]

[0046] Where D is the vector of all design variables, is the design variable vector of the rib configuration control point, n is the number of ribs, is the set of all design variables, C is the objective function of the optimization model, v is the test function defined in the design domain, Γ u represents the design domain boundary, and:

[0047]

[0048] H(·) indicates the use of Heaviside function processing, the parameter δ is used to control the degree of regularization, and a minimum positive value α is introduced to ensure the non-singularity of the overall stiffness matrix of the structure. Its expression is:

[0049]

[0050] Among them, φ S (x) is the topological description function of the structure, and the signed distance function is used as the topological description function of the ribs and the flow channel. ε is the second-order linear strain tensor, and f is the strain acting on the Neumann boundary Γ. t The body force on the Neumann boundary Γ t The surface traction on is the Dirichlet boundary Γ u For simplicity, it is assumed to be a zero matrix. is the upper limit of the optimized volume ratio, is the upper limit vector of the design variables, D is the lower limit vector of the design variables, is the fourth-order isotropic elastic tensor of the solid material;

[0051] Fourth-order isotropic elastic tensor of solid material The expression is:

[0052]

[0053] in, and δ are the fourth-order and second-order identity tensors respectively, E is the elastic modulus of the material, and ν is the Poisson's ratio of the material.

[0054] In at least one embodiment of the present application, in step three, a parameter optimization design method is used to optimize the dimensions of the frame web, flow channel, and ribs of the frame structure.

[0055] The invention has at least the following beneficial technical effects:

[0056] The multifunctional integrated structural design method for load-bearing and medium transportation of the present application integrates the load-bearing structure and the medium transportation pipeline into an integrated design. While ensuring the medium transportation function, it has the load-bearing capacity of the load-bearing structure, reduces the number of parts, reduces the assembly process and time, reduces redundant structures, and achieves lightweight. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 It is a schematic diagram of the front and side of a multifunctional integrated structure for carrying and transporting medium according to an embodiment of the present application;

[0058] Figure 2 It is a schematic diagram of the back side of a multifunctional integrated structure for carrying and transporting medium according to an embodiment of the present application;

[0059] Figure 3 It is a deformation cloud diagram of a multifunctional integrated structure for load bearing and medium transport according to one embodiment of the present application;

[0060] Figure 4 It is a stress cloud diagram of a multifunctional integrated structure for load bearing and medium transport according to one embodiment of the present application;

[0061] Figure 5 It is a schematic diagram of the outlet flow of a multifunctional integrated structure for load bearing and medium transport according to one embodiment of the present application.

[0062] in:

[0063] 1-front side of the load-bearing frame; 2-second supply channel; 3-first supply channel; 4-front ribs; 5-first supply channel inlet; 6-second supply channel inlet; 7-first supply channel outlet; 8-second collecting channel inlet; 9-back side of the load-bearing frame; 10-second collecting channel; 11-first collecting channel; 12-back ribs; 13-first collecting channel outlet; 14-second collecting channel outlet; 15-first collecting channel inlet; 16-second supply channel outlet. DETAILED DESCRIPTION

[0064] In order to make the purpose, technical scheme and advantages of the implementation of this application clearer, the technical scheme in the embodiment of this application will be described in more detail below in conjunction with the drawings in the embodiment of this application. In the drawings, the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The described embodiments are part of the embodiments of this application, not all of them. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain this application, and should not be construed as limitations on this application. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application. The embodiments of this application are described in detail below in conjunction with the drawings.

[0065] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the scope of protection of the present application.

[0066] The following is combined with Figures 1 to 5 This application is described in further detail.

[0067] The present application provides a design method for a multifunctional integrated structure for load bearing and medium transport, comprising the following steps:

[0068] Step 1: Select the frame structure of the aircraft body as the design object according to the load-bearing capacity requirements and the medium transport function requirements;

[0069] Step 2: extract the load borne by the frame structure from the whole machine load as the mechanical load input, and carry out configuration optimization design of the frame structure according to the cooling medium flow demand to obtain the optimal configuration of the frame structure;

[0070] Step 3: Optimize the size of the frame structure by using a parameter optimization design method to obtain an optimal size parameter combination of the frame structure;

[0071] Step 4: According to the optimal configuration and optimal size parameter combination, the frame structure is manufactured using an adaptive 3D printing process.

[0072] In the design method of the multifunctional integrated structure for load bearing and medium transport of the present application, in step 1, according to the load bearing capacity requirements and the medium transport function requirements, the frame structure in the aircraft body as the design object is selected as the 15th frame. The frame structure includes: a frame web, the frame web has a load bearing frame front side 1 and a load bearing frame back side 9, the load bearing frame front side 1 and the load bearing frame back side 9 are both provided with medium transport flow channels and ribs, the flow channel of the load bearing frame front side 1 is used to supply the medium, and the flow channel of the load bearing frame back side 9 is used to collect the medium.

[0073] Specifically, Figure 1As shown, the front side 1 of the bearing frame is provided with a first supply channel 3, a second supply channel 2 and a front side rib 4. The channel wall of the first supply channel 3 is connected to the front side 1 of the bearing frame, one end of the first supply channel 3 is provided with a first supply channel inlet 5, and the other end of the first supply channel 3 is provided with a first supply channel outlet 7; the channel wall of the second supply channel 2 is connected to the front side 1 of the bearing frame, one end of the second supply channel 2 is provided with a second supply channel inlet 6, and the other end of the second supply channel 2 passes through the frame web and is provided with a second supply channel outlet 16 on the back side 9 of the bearing frame; the front side rib 4 is provided on the front side 1 of the bearing frame. The first supply channel 3 and the second supply channel 2 are used to transport the medium of the two regions respectively, the first supply channel inlet 5 and the second supply channel inlet 6 are used to achieve uniform distribution of the medium of the two regions, and the first supply channel outlet 7 and the second supply channel outlet 16 are used to connect with the medium inlet of the docking element to supply the medium to the docking element. Preferably, the two supply channel outlets are arranged in a direction away from the frame web to facilitate connection with the docking element.

[0074] like Figure 2 As shown, the back side 9 of the bearing frame is provided with a first collecting channel 11, a second collecting channel 10 and a back rib 12. The channel wall of the first collecting channel 11 is connected to the back side 9 of the bearing frame, one end of the first collecting channel 11 is provided with a first collecting channel outlet 13, and the other end of the first collecting channel 11 is provided with a first collecting channel inlet 15; the channel wall of the second collecting channel 10 is connected to the back side 9 of the bearing frame, one end of the second collecting channel 10 is provided with a second collecting channel outlet 14, and the other end of the second collecting channel 10 passes through the frame web and is provided with a second collecting channel inlet 8 on the front side 1 of the bearing frame; the back rib 12 is provided on the back side 9 of the bearing frame. The first collecting channel inlet 15 and the second collecting channel inlet 8 are used to connect with the medium outlet of the docking element to collect the medium in the docking element, and the first collecting channel 11 and the second collecting channel 10 are used to transport the medium of the two regions respectively, and the first collecting channel outlet 13 and the second collecting channel outlet 14 are used to collect the medium of the two regions. Likewise, the two collecting channel inlets are preferably arranged in a direction away from the frame web to facilitate connection with the docking element.

[0075] In a preferred embodiment of the present application, the frame web includes an upper web portion and a lower web portion, the upper boundary curve of the upper web portion and the lower boundary curve of the lower web portion have different curvatures, and the frame web as a whole is a bilaterally symmetrical structure. Advantageously, in this embodiment, a through hole for other flow channels to pass through is provided on the frame web.

[0076] In the design method of the multifunctional integrated structure for load bearing and medium transport of the present application, in step 2, the load borne by the 15th frame is extracted from the whole machine load as the mechanical load input, and according to the requirement of cooling medium flow rate of 10L / min, the frame structure is optimized and designed to obtain the optimal configuration of the frame structure.

[0077] In a preferred embodiment of the present application, the optimal configuration of the frame structure includes: the first supply channel 3, the second supply channel 2, the first collecting channel 11 and the second collecting channel 10 are all B-spline curve channels obtained through topological optimization technology; the configuration of the first supply channel 3 and the first collecting channel 11 presents the characteristics of one divided into four and four divided into eight, and has good uniform medium transport and load-bearing performance; the front side ribs 4 and the back side ribs 12 are B-spline curve ribs obtained through topological optimization technology.

[0078] In this embodiment, the optimization model for topological optimization of the second supply channel 2 is:

[0079]

[0080] Where D is the vector of all design variables, is the design variable vector of the flow channel configuration control point, is the design variable vector of the rib configuration control point, n is the number of ribs, m is the total number of channels and ribs, is the set of all design variables, C mix is the objective function of the optimization model;

[0081] The objective function C of the optimization model mix It consists of two weighted parts, with weighted coefficients a and b respectively. The first half is the calculation formula for the total elastic strain energy of the structure, where v is a test function defined in the design domain, and Γ u is the design domain boundary, and:

[0082]

[0083] The second half is the velocity difference calculation formula for multi-outlet flow channels, where v i is the fluid velocity of the ith flow channel, v ave is the average value of the fluid flow rate in all flow channels;

[0084] H(·) indicates the use of Heaviside function processing, the parameter δ is used to control the degree of regularization, and a minimum positive value α is introduced to ensure the non-singularity of the overall stiffness matrix of the structure. Its expression is:

[0085]

[0086] Among them, φ S (x) is the topological description function of the structure, and the signed distance function is used as the topological description function of the ribs and the flow channel. ε is the second-order linear strain tensor, and f is the strain acting on the Neumann boundary Γ. t The body force on the Neumann boundary Γ tThe surface traction on is the Dirichlet boundary Γ u For simplicity, it is assumed to be a zero matrix. is the upper limit of the optimized volume ratio, is the upper limit vector of the design variables, D is the lower limit vector of the design variables, is the fourth-order isotropic elastic tensor of the solid material;

[0087] Fourth-order isotropic elastic tensor of solid material The expression is:

[0088]

[0089] in, and δ are the fourth-order and second-order identity tensors respectively, E is the elastic modulus of the material, and ν is the Poisson's ratio of the material.

[0090] The optimization model for topological optimization of the second collecting flow channel 10 is:

[0091]

[0092] Where D is the vector of all design variables, is the design variable vector of the flow channel configuration control point, is the design variable vector of the rib configuration control point, n is the number of ribs, m is the total number of channels and ribs, is the set of all design variables, C mix is the objective function of the optimization model;

[0093] The objective function C of the optimization model mix It consists of two weighted parts, with weighted coefficients a and b respectively. The first half is the calculation formula for the total elastic strain energy of the structure, where v is a test function defined in the design domain, and Γ u is the design domain boundary, and:

[0094]

[0095] The second half is the velocity difference calculation formula for multi-outlet flow channels, where v i is the fluid velocity of the ith flow channel; v ave is the average value of the fluid flow rate in all flow channels;

[0096] H(·) indicates the use of Heaviside function processing, the parameter δ is used to control the degree of regularization, and a minimum positive value α is introduced to ensure the non-singularity of the overall stiffness matrix of the structure. Its expression is:

[0097]

[0098] Among them, φ S (x) is the topological description function of the structure, and the signed distance function is used as the topological description function of the ribs and the flow channel. ε is the second-order linear strain tensor, and f is the strain acting on the Neumann boundary Γ t The body force on the Neumann boundary Γ t The surface traction on is the Dirichlet boundary Γ u For simplicity, it is assumed to be a zero matrix. is the upper limit of the optimized volume ratio, is the upper limit vector of the design variables, D is the lower limit vector of the design variables, is the fourth-order isotropic elastic tensor of the solid material;

[0099] Fourth-order isotropic elastic tensor of solid material The expression is:

[0100]

[0101] in, and δ are the fourth-order and second-order identity tensors respectively, E is the elastic modulus of the material, and ν is the Poisson's ratio of the material.

[0102] The optimization model for topological optimization of the front rib 4 and the back rib 12 is:

[0103]

[0104] Where D is the vector of all design variables, is the design variable vector of the rib configuration control point, n is the number of ribs, is the set of all design variables, C is the objective function of the optimization model, v is the test function defined in the design domain, Γ u represents the design domain boundary, and:

[0105]

[0106] H(·) indicates the use of Heaviside function processing, the parameter δ is used to control the degree of regularization, and a minimum positive value α is introduced to ensure the non-singularity of the overall stiffness matrix of the structure. Its expression is:

[0107]

[0108] Among them, φ S(x) is the topological description function of the structure, and the signed distance function is used as the topological description function of the ribs and the flow channel. ε is the second-order linear strain tensor, and f is the strain acting on the Neumann boundary Γ. t The body force on the Neumann boundary Γ t The surface traction on is the Dirichlet boundary Γ u For simplicity, it is assumed to be a zero matrix. is the upper limit of the optimized volume ratio, is the upper limit vector of the design variables, D is the lower limit vector of the design variables, is the fourth-order isotropic elastic tensor of the solid material;

[0109] Fourth-order isotropic elastic tensor of solid material The expression is:

[0110]

[0111] in, and δ are the fourth-order and second-order identity tensors respectively, E is the elastic modulus of the material, and ν is the Poisson's ratio of the material.

[0112] In the design method of the multifunctional integrated structure for load bearing and medium transport of the present application, in step three, a parameter optimization design method is adopted to optimize the dimensions of the frame web, the wall thickness and height of the flow channel pipeline, and the height and thickness of the ribs of the frame structure.

[0113] The design method of the multifunctional integrated structure for load bearing and medium transport of the present application, finally, in step four, according to the optimal configuration and optimal size parameter combination obtained above, an adapted 3D printing process is used to manufacture the frame structure.

[0114] In one embodiment of the present application, Figure 3 , 4 As shown in Figures 5 and 5, the deformation cloud map, stress cloud map and outlet flow diagram of the multifunctional integrated structure for load bearing and medium transportation obtained by the design method of the present application show that its maximum displacement is 1.2 mm, the maximum stress is 215 MPa, and the outlet flows are similar. This shows that the multifunctional integrated structure for load bearing and medium transportation obtained by the present application has good load bearing performance and medium transportation performance.

[0115] The design method of the multifunctional integrated structure for load bearing and medium transport of the present application can obtain an integrated structure for use with a radiator. The radiator is provided with an interface adapted to the integrated load-bearing frame. The integrated load-bearing frame is connected to the medium inlet of the radiator through 8 first supply channel outlets 7 and 1 second supply channel outlet 16 to supply the medium to the radiator, and is connected to the medium outlet of the radiator through 8 first collecting channel inlets 15 and 1 second collecting channel inlet 8 to collect the medium in the radiator.

[0116] The multifunctional integrated structural design method for load-bearing and medium transportation of the present application solves the problems of the existing structure with a large number of parts, many assembly processes, long assembly time, and weakened load-bearing capacity of the load-bearing structure. The integrated design of the load-bearing structure and the medium transportation pipeline improves the load-bearing capacity of the load-bearing structure, realizes the uniform distribution of the medium, reduces the assembly process and time, reduces the number of parts, is easy to promote, and has great practical value.

[0117] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A design method for a multifunctional integrated structure for load bearing and medium transport, characterized in that: include: Step 1: Select the frame structure of the aircraft body as the design object according to the load-bearing capacity requirements and the medium transport function requirements; Step 2: extracting the load borne by the frame structure from the whole machine load as a mechanical load input, and performing configuration optimization design on the frame structure according to the cooling medium flow requirement to obtain the optimal configuration of the frame structure; Step 3: Optimize the size of the frame structure by using a parameter optimization design method to obtain an optimal size parameter combination of the frame structure; Step 4: According to the optimal configuration and the optimal size parameter combination, the frame structure is manufactured using an adapted 3D printing process.

2. The design method of a multifunctional integrated structure for load bearing and medium transport according to claim 1 is characterized in that: In step 1, according to the requirements of bearing capacity and medium transport function, the frame structure in the aircraft body as the design object is selected as the 15th frame, and the frame structure includes: a frame web, and the frame web has a load-bearing frame front side and a load-bearing frame back side, wherein: The front side of the load-bearing frame is provided with a first supply channel, a second supply channel and front side ribs; The back side of the load-bearing frame is provided with a first collecting flow channel, a second collecting flow channel and back side ribs.

3. The design method of a multifunctional integrated structure for load bearing and medium transport according to claim 2 is characterized in that: The frame web includes an upper web portion and a lower web portion, and an upper boundary curve of the upper web portion and a lower boundary curve of the lower web portion have different curvatures.

4. The design method of a multifunctional integrated structure for load bearing and medium transport according to claim 3 is characterized in that: The frame web is a bilaterally symmetrical structure.

5. The design method of a multifunctional integrated structure for load bearing and medium transport according to claim 4 is characterized in that: In step 2, the optimal configuration of the frame structure includes: The first supply flow channel, the second supply flow channel, the first collecting flow channel and the second collecting flow channel are all B-spline curve flow channels obtained by topology optimization technology; The first supply flow channel and the first collecting flow channel both adopt a one-divided-into-four or four-divided-into-eight structure; The front side ribs and the back side ribs are B-spline curve ribs obtained through topology optimization technology.

6. The design method of a multifunctional integrated structure for load bearing and medium transport according to claim 5 is characterized in that: The optimization model for topological optimization of the second supply channel is: Where D is the vector of all design variables, is the design variable vector of the flow channel configuration control point, is the design variable vector of the rib configuration control point, n is the number of ribs, m is the total number of channels and ribs, is the set of all design variables, C mix is the objective function of the optimization model; The objective function C of the optimization model mix It consists of two weighted parts, with weighted coefficients a and b respectively. The first half is the calculation formula for the total elastic strain energy of the structure, where v is a test function defined in the design domain, and Γ u is the design domain boundary, and: The second half is the velocity difference calculation formula for multi-outlet flow channels, where v i is the fluid velocity of the ith flow channel, v ave is the average value of the fluid flow rate in all flow channels; H(·) indicates the use of Heaviside function processing, the parameter δ is used to control the degree of regularization, and a minimum positive value α is introduced to ensure the non-singularity of the overall stiffness matrix of the structure. Its expression is: Among them, φ S (x) is the topological description function of the structure, and the signed distance function is used as the topological description function of the ribs and the flow channel. ε is the second-order linear strain tensor, and f is the strain acting on the Neumann boundary Γ. t The body force on the Neumann boundary Γ t The surface traction on is the Dirichlet boundary Γ u For simplicity, it is assumed to be a zero matrix. is the upper limit of the optimized volume ratio, is the upper limit vector of the design variables, D is the lower limit vector of the design variables, is the fourth-order isotropic elastic tensor of the solid material; Fourth-order isotropic elastic tensor of solid material The expression is: in, and δ are the fourth-order and second-order identity tensors respectively, E is the elastic modulus of the material, and ν is the Poisson's ratio of the material.

7. The design method of a multifunctional integrated structure for load bearing and medium transport according to claim 6 is characterized in that: The optimization model for topology optimization of the second collecting channel is: Where D is the vector of all design variables, is the design variable vector of the flow channel configuration control point, is the design variable vector of the rib configuration control point, n is the number of ribs, m is the total number of channels and ribs, is the set of all design variables, C mix is the objective function of the optimization model; The objective function C of the optimization model mix It consists of two weighted parts, with weighted coefficients a and b respectively. The first half is the calculation formula for the total elastic strain energy of the structure, where v is a test function defined in the design domain, and Γ u is the design domain boundary, and: The second half is the velocity difference calculation formula for multi-outlet flow channels, where v i is the fluid velocity of the ith flow channel; v ave is the average value of the fluid flow rate in all flow channels; H(·) indicates the use of Heaviside function processing, the parameter δ is used to control the degree of regularization, and a minimum positive value α is introduced to ensure the non-singularity of the overall stiffness matrix of the structure. Its expression is: Among them, φ S (x) is the topological description function of the structure, and the signed distance function is used as the topological description function of the ribs and the flow channel. ε is the second-order linear strain tensor, and f is the strain acting on the Neumann boundary Γ t The body force on the Neumann boundary Γ t The surface traction on is the Dirichlet boundary Γ u For simplicity, it is assumed to be a zero matrix. is the upper limit of the optimized volume ratio, is the upper limit vector of the design variables, D is the lower limit vector of the design variables, is the fourth-order isotropic elastic tensor of the solid material; Fourth-order isotropic elastic tensor of solid material The expression is: in, and δ are the fourth-order and second-order identity tensors respectively, E is the elastic modulus of the material, and ν is the Poisson's ratio of the material.

8. The design method of a multifunctional integrated structure for load bearing and medium transport according to claim 7 is characterized in that: The optimization model for topological optimization of the front side ribs and the back side ribs is: Where D is the vector of all design variables, is the design variable vector of the rib configuration control point, n is the number of ribs, is the set of all design variables, C is the objective function of the optimization model, v is the test function defined in the design domain, Γ u represents the design domain boundary, and: H(·) indicates the use of Heaviside function processing, the parameter δ is used to control the degree of regularization, and a minimum positive value α is introduced to ensure the non-singularity of the overall stiffness matrix of the structure. Its expression is: Among them, φ S (x) is the topological description function of the structure, and the signed distance function is used as the topological description function of the ribs and the flow channel. ε is the second-order linear strain tensor, and f is the strain acting on the Neumann boundary Γ. t The body force on the Neumann boundary Γ t The surface traction on is the Dirichlet boundary Γ u For simplicity, it is assumed to be a zero matrix. is the upper limit of the optimized volume ratio, is the upper limit vector of the design variables, D is the lower limit vector of the design variables, is the fourth-order isotropic elastic tensor of the solid material; Fourth-order isotropic elastic tensor of solid material The expression is: in, and δ are the fourth-order and second-order identity tensors respectively, E is the elastic modulus of the material, and ν is the Poisson's ratio of the material.

9. The design method of a multifunctional integrated structure for load bearing and medium transport according to claim 8, characterized in that: In step three, a parameter optimization design method is used to optimize the dimensions of the frame web, flow channel, and ribs of the frame structure.

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