Simulation estimation method for rigidity of flexible aviation wire harness

Abstract

The invention belongs to the technical field of aviation intelligent manufacturing, and discloses a flexible aviation wire harness rigidity simulation estimation method, which comprises the following steps: firstly, splitting a wire harness assembly structure into wires and cables, a wave-proof sleeve, a braided sheath and the like, and calculating the rigidity characteristic according to the influence of geometric structure parameters and material parameters of various wires and cables on the rigidity characteristic; further refining and classifying, and carrying out a rigidity characteristic test of the material; by fully collecting test results of geometric structures and mechanical characteristics of various electric wires and cables and combining a standard electric wire rigidity calculation function and a cable bundle rigidity calculation function of flexible pipeline simulation software, a rigidity characteristic library of aviation electric wires and cables and wire harness materials can be established; and finally, based on the stiffness characteristic library, realizing analogue simulation of multiple types of flexible wire harnesses. According to the invention, the effective rigidity parameter of the wire harness assembly can be estimated based on the rigidity characteristics of the basic wire cable and the wire harness material, and the rigidity test work of the flexible wire harness is greatly simplified.

Description

Technical Field

[0001] The invention application belongs to the technical field of aviation harness design and manufacturing in aviation intelligent manufacturing, and specifically relates to a method for simulating and estimating the stiffness of a flexible aviation harness. Background Art

[0002] With the profound transformation of the aviation industry to multi-electric and all-electric architecture, the interconnection layout of the aircraft's internal wiring harness has shown increasing complexity. As one of the core components for the realization of aircraft system performance, the safety and reliability of the wiring harness has become one of the core elements to ensure flight safety. Any slight change in its performance may have a significant impact on the safe operation of the aircraft. As a key flexible component, the performance evaluation of the wiring harness assembly has far exceeded the scope of a single electrical performance, and its performance evaluation system must fully cover the dual dimensions of electrical and mechanical. Given that the mechanical properties of the wiring harness assembly have a vital impact on the realization of product functions and the overall system reliability after installation. Therefore, it is necessary to conduct experimental research on the mechanical properties of the wiring harness assembly. Therefore, in the product design optimization process, the introduction of advanced flexible pipeline simulation software has gradually evolved into a crucial technological innovation. This technology not only enhances the interactive simulation capabilities of engineers in the product design process, but also can easily find the optimal routing, length and shape of the flexible wiring harness assembly, while implementing comprehensive stress-strain inspection, virtual assembly verification, and real-time motion analysis of the wiring harness. The above technologies can provide a solid verification foundation for flexible pipelines and related components in the early stages of product development, thereby effectively reducing prototype design and iteration, significantly saving time and economic costs, and promoting the improvement of product quality and the enhancement of the durability of flexible components.

[0003] Flexible pipeline simulation design relies on the accurate measurement of the effective stiffness values ​​of cables or harnesses, such as effective bending stiffness, torsional stiffness, tensile stiffness, etc. Since harness components are heterogeneous materials such as various types of wires and cables, protective materials, etc., it is impossible to simply combine the material mechanical properties (such as Young's modulus, shear modulus, Poisson's ratio, etc.) and structural geometric parameters in the calculation. In principle, it is feasible to measure the effective stiffness values ​​of all cables and harness components, but the method of experimental measurement of harness components of actual configuration during field operation is time-consuming and labor-intensive, and there are problems such as the need for a large number of iterations in aircraft harness design and the lack of specific harness prototypes in the early stages of development. Therefore, in response to the above problems, the characteristics of the basic wires and cable materials and harness protective materials of the harness and the aircraft harness manufacturing process methods are fully combined to estimate the effective stiffness values ​​of the harness, further improve the simulation accuracy, and enhance the reliability of the aviation harness. Summary of the invention

[0004] The present invention application proposes a flexible aviation harness stiffness simulation estimation method, which simplifies the process of measuring the effective stiffness of harness components, shortens the simulation cycle, and reduces the simulation cost.

[0005] In order to achieve the above invention objectives, the technical solutions adopted in this application are as follows:

[0006] A method for estimating the effective stiffness of a flexible wiring harness is proposed. Through a limited number of sample tests, a library of structural parameters and material parameters of aviation wires and cables and a library of stiffness parameters of wiring harness protection materials are established. The wire and cable bundle stiffness calculation model of the flexible pipeline simulation software is used to estimate the effective stiffness of wiring harness components of any configuration.

[0007] The specific steps include:

[0008] According to the composition structure of aviation wires, they are divided into wire conductors and insulation layers.

[0009] A wire conductor structure and material parameter library is established based on the geometric structure characteristics and material properties of the wire conductor. The wire conductor structure and material parameters include: conductor identification, conductor specification, number of wire cores, single strand diameter, conductor lay length, conductor material, conductor density, conductor elastic modulus, conductor Poisson's ratio, conductor shear modulus, etc.

[0010] According to the material type and molding method of the wire insulation layer, a wire insulation layer structure and material parameter library is established. The wire insulation layer structure and material parameters include: insulation layer thickness, insulation layer inner diameter, insulation layer form, insulation material density, insulation elastic modulus, insulation Poisson's ratio, insulation shear modulus, etc.

[0011] According to the wire conductor structure, material parameter library and insulation layer structure, material parameter library, the wire stiffness parameter library of aviation wire is established by using the wire stiffness calculation model of flexible pipeline simulation software. The parameters of the wire stiffness parameter library include: wire part number, conductor information, insulation layer information, length density, bending stiffness, torsional stiffness and tensile stiffness, etc.

[0012] According to the composition structure of aviation cables, they are divided into wires, cable shielding layers and cable sheaths.

[0013] According to the cable shielding layer structural parameters and material properties, a cable shielding layer stiffness parameter library is established. The cable shielding layer material parameters include: cable shielding identification, shielding wire material, shielding wire form, shielding coverage, shielding layer thickness, shielding layer length density, bending stiffness, torsional stiffness, tensile stiffness, etc.

[0014] According to the cable sheath structural parameters and material properties, a cable sheath material parameter library is established through the stiffness test method. The cable sheath material parameters include: sheath material identification, sheath material, sheath material thickness, sheath form, sheath length density, bending stiffness, torsional stiffness, tensile stiffness, etc.

[0015] An aviation cable stiffness parameter library is established. According to the wire stiffness parameter library, cable shielding layer stiffness parameter library and cable sheath parameter library, the cable bundle stiffness calculation model of the flexible pipeline simulation software is used to establish an aviation cable stiffness parameter library. The parameters include: cable part number, number of wires, part number of included wires, wire position coordinate information, shielding layer information, sheath information, cable length density, bending stiffness, torsional stiffness, tensile stiffness, etc.

[0016] According to the geometric structure parameters and material properties of the wire harness protection materials (including PTFE protection, wave-proof sleeves, mechanical braided sleeves, etc.), the material parameter library of the wire harness protection materials is established through the stiffness test method. The material parameters include: protection material identification, protection material specifications, process materials (methods), protection material thickness, protection material inner diameter, protection material length / density, bending stiffness, torsional stiffness and tensile stiffness, etc.

[0017] Using the cable bundle stiffness calculation function of the flexible pipeline simulation software, the wires, cables and harness protection materials that make up the harness are selected from the material library to calculate the effective stiffness value of the harness.

[0018] Compared with the prior art, the beneficial effects of this application are:

[0019] 1. This method structurally decomposes the standard materials commonly used in aviation wiring harnesses, such as wires and cables, wiring harness protection materials, etc., and tests the stiffness of a limited number of standard material components such as conductors, insulation layers, cable shielding layers, cable sheaths, wiring harness protection materials, etc., and combines the wire stiffness calculation model and cable bundle stiffness calculation model of the flexible pipeline simulation software to achieve the effective stiffness numerical estimation of any configuration wiring harness assembly, effectively simplifying the wiring harness stiffness measurement.

[0020] 2. This application simplifies the process of measuring the effective stiffness of wiring harness components, shortens the simulation cycle and reduces simulation costs.

[0021] The present application is further described below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention.

[0023] In the attached picture:

[0024] Figure 1 It is a schematic diagram of the principle of the present invention;

[0025] Figure 2 It is a schematic diagram of the wire structure;

[0026] Figure 3 It is a schematic diagram of the wire strand structure of the wire conductor;

[0027] Figure 4 It is a schematic diagram of the cable structure;

[0028] Figure 5 This is a typical cross-sectional diagram of a cable;

[0029] Figure 6 This is a schematic diagram of an unprotected wire harness bundle;

[0030] Figure 7 This is a diagram of a protected wire harness bundle. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0032] The present invention provides a method for estimating the effective stiffness of a flexible wiring harness based on flexible pipeline simulation software, such as Figure 1 The flexible part of the harness assembly is made of standard wires and cables. According to the actual mechanical and electromagnetic function requirements, wave-proof sleeve materials, mechanical braiding materials and other harness process materials can be further tied outside the cable bundle. The harness assembly is decomposed according to the standard material structure, such as Figure 1 This method is based on the decomposition of various standard materials of the wire harness, and through the stiffness test and calculation model method of the standard materials, the geometric structure parameter library and material stiffness parameter library of the relevant standard materials are established. Finally, the cable bundle calculation model of the flexible pipeline simulation software is used to estimate the effective stiffness of the flexible wire harness, which specifically includes:

[0033] Step 1: Construct the wire conductor geometry and material parameter library. The wire conductor strand structure is as follows: Figure 3 As shown, according to the wire stiffness calculation model in the flexible pipeline simulation software, the wire conductor parameter library includes: conductor identification, conductor specification, number of strands, single strand diameter, conductor lay length, conductor material, conductor density, conductor elastic modulus, conductor Poisson's ratio, conductor shear modulus, etc. The relevant material parameters can be obtained through the material manual.

[0034] Step 2: Construct a parameter library for the insulation layer materials of wires. Take the insulation layer materials (such as PTFE, ETFE, XLETFE, etc.) and forms (such as extrusion and wrapping) of aviation wires as combination units to establish a parameter library for the insulation layer materials of wires. The specific parameters include: insulation layer material, insulation layer thickness, insulation layer inner diameter, insulation layer form, insulation material density, insulation elastic modulus, insulation Poisson's ratio, insulation shear modulus, etc. The relevant material parameters can be found in the manual

[0035] Step 3: Construct a parameter library of aviation wire stiffness characteristics. Wire materials are composed of wire conductors and insulation layers. According to the detailed material parameters of the conductors and insulation layer materials that make up the wires, the wire stiffness calculation model in the flexible pipeline simulation software is used to calculate the stiffness characteristics of specific brands of wires, including length density, bending stiffness, torsional stiffness, and tensile stiffness.

[0036] Step 4: Construct a parameter library for aviation cable shielding layer materials. Using aviation cable shielding layer materials (such as tinned copper, silver-plated copper, nickel-plated copper, stainless steel, etc.) and shielding wire forms (round, flat) as combined units, establish a parameter library for wire insulation layer materials through stiffness testing methods. Specific parameters include: cable shielding identification, shielding wire material, shielding wire form, shielding coverage, shielding layer thickness, shielding layer length density, bending stiffness, torsional stiffness, tensile stiffness, etc.

[0037] Step 5: Construct a parameter library for aviation cable sheath materials. Taking the sheath materials (such as PTFE, ETFE, XLETFE, etc.) and forms (such as extrusion and wrapping) of aviation cables as combined units, a cable sheath material parameter library is established through the stiffness test method. The specific parameters include: sheath material identification, sheath material, sheath material thickness, sheath form, sheath length density, bending stiffness, torsional stiffness, tensile stiffness, etc.

[0038] Step 6: Construct the aviation cable stiffness characteristic parameter library. Aviation cable materials can be composed of a specific number of standard wires in a specific structural form, cable shielding layer and cable sheath, such as Figure 4 According to the standard wire stiffness parameter library (step three), cable shield material parameter library (step four) and cable sheath material parameter library (step five), as well as the position coordinate information of the standard wire, Figure 5 As shown in the figure, the cable bundle stiffness calculation model in the flexible pipeline simulation software is used to calculate the stiffness characteristics of specific brands of cables, including length density, bending stiffness, torsional stiffness and tensile stiffness, and establish an aviation cable stiffness parameter library.

[0039] Step 7: Build a parameter library for wire harness protection materials. In aviation wire harness products, wire harness protection materials are usually composed of standard materials (such as wave-proof sleeves, mechanical braided sleeves, etc.) combined with wire harness process materials. For example, PTFE tape needs to be wrapped between the wave-proof sleeve and the wire harness bundle. Therefore, the stiffness of the wire harness protection material needs to be combined with specific process methods and obtained through stiffness testing. The material parameters of the wire harness protection material include: protection material identification, protection material specifications, process materials (methods), protection material thickness, protection material inner diameter, protection material length density, bending stiffness, torsional stiffness and tensile stiffness, etc.

[0040] Step 8: Estimation of the effective stiffness of the flexible harness. The harness assembly includes an unprotected harness bundle ( Figure 6 ) and protected harness bundles ( Figure 7 ), so the effective stiffness value of the flexible harness can be reasonably estimated based on the stiffness parameters of aviation wires (step three), aviation cables (step six) and the stiffness parameters of harness protection materials (step seven), combined with the cable bundle stiffness calculation model of the flexible harness simulation software.

[0041] So far, the purpose of the present invention has been achieved.

[0042] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for simulating and estimating the stiffness of a flexible aviation harness, characterized in that: The steps include: According to the composition structure of aviation wires and cables and wiring harnesses, the wiring harness assembly structure can be divided into wires and cables, wave-proof sleeves, braided sheaths and other levels. Wires and cables can be further subdivided into wires, insulation layers, shielding layers, sheaths and other levels according to the composition structure; Establish wire conductor structure and material parameter library according to wire conductor geometric structure characteristics and material properties; According to the types of wire insulation materials, a wire insulation material parameter library is established through the stiffness test method; According to the conductor structure, material parameters and insulation material parameters of the wire, the wire stiffness calculation model of the flexible pipeline simulation software is used to establish the aviation wire stiffness parameter library; According to the structural parameters and material properties of the cable shielding layer, a cable shielding layer material parameter library is established through the stiffness test method; According to the cable sheath structural parameters and material properties, a cable sheath material parameter library is established through the stiffness test method; According to the wire stiffness parameter library, cable shield material parameter library and cable sheath material parameter library, the cable bundle stiffness calculation model of the flexible pipeline simulation software is used to establish the aviation cable stiffness parameter library; According to the structural parameters and material properties of the wire harness protection material and combined with the assembly process of the protection material, a material parameter library of the wire harness protection material is established; Using the cable bundle stiffness calculation function of the flexible pipeline simulation software, the wires, cables and harness protection materials that make up the harness bundle are selected from the material library to calculate the effective stiffness value of the harness.

2. The method for simulating and estimating the stiffness of a flexible aviation harness according to claim 1, characterized in that: The wire conductor structure and material parameter library includes: conductor specifications, number of wire core strands, single strand diameter, conductor lay length, conductor material, conductor density, conductor elastic modulus, conductor Poisson's ratio, conductor shear modulus, etc.

3. The method for simulating and estimating the stiffness of a flexible aviation harness according to claim 1, characterized in that: The wire conductor structure and material parameter library includes: insulation layer thickness, insulation layer inner diameter, insulation layer form, insulation material density, insulation elastic modulus, insulation Poisson's ratio, insulation shear modulus, etc.

4. The method for simulating and estimating the stiffness of a flexible aviation harness according to claim 1, characterized in that: The aviation wire stiffness parameter library includes: wire part number, conductor information, insulation layer information, length density, bending stiffness, torsional stiffness and tensile stiffness, etc.

5. The method for simulating and estimating the stiffness of a flexible aviation harness according to claim 1, characterized in that: The cable shielding layer material parameter library includes: cable shielding identification, shielding wire material, shielding wire form, shielding layer thickness, shielding layer length density, bending stiffness, torsional stiffness, tensile stiffness, etc.

6. The method for simulating and estimating the stiffness of a flexible aviation harness according to claim 1, characterized in that: The cable sheath material parameter library includes: sheath material identification, sheath material, sheath material thickness, sheath form, sheath length density, bending stiffness, torsional stiffness, tensile stiffness, etc.

7. The method for simulating and estimating the stiffness of a flexible aviation harness according to claim 1, characterized in that: The aviation cable stiffness parameter library includes: cable part number, wire quantity, part number of wires, wire position coordinate information, shielding layer information, sheath information, cable length density, bending stiffness, torsional stiffness, tensile stiffness, etc.

8. The method for simulating and estimating the stiffness of a flexible aviation harness according to claim 1, characterized in that: The wire harness protection material parameter library includes: protection material identification, protection material specifications, process materials or methods, protection material thickness, protection material inner diameter, protection material length density, bending stiffness, torsional stiffness and tensile stiffness, etc.

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