Method and device for determining guide rail structure of electromagnetic emission system, equipment and medium

Abstract

The invention provides a method, a device, equipment and a medium for determining a guide rail structure of an electromagnetic emission system, in the method for determining the guide rail structure of the electromagnetic emission system, a basic model of the electromagnetic emission system is established, and the basic model comprises two parallel flat guide rails and an armature; modifying the basic model to generate convex guide rail models with different structural parameters; performing a power-on experiment on the convex guide rail models with different structural parameters to obtain line current density distribution information of the rear edge of the contact interface; and determining first structure information of the convex guide rail model based on the line current density distribution information. According to the method, the guide rail structure capable of effectively inhibiting the speed skin effect can be quickly and accurately determined through the convex guide rail models with different structure parameters.

Description

Technical Field

[0001] The present application relates to the technical field of electromagnetic launch systems, and in particular to a method, device, and medium for determining a guide rail structure of an electromagnetic launch system. Background Art

[0002] The Electromagnetic Launch System (EMLS) is a kinetic weapon in which an energized armature, in a strong magnetic field generated by an energized rail, experiences electromagnetic forces, propelling the projectile. The extremely high initial velocity of the launch is due to the enormous instantaneous pulse current. This not only generates significant Joule heating but also subjects the EMLS launch system to a complex transient environment of electromagnetic, magnetic, thermal, and mechanical fields. This places stringent demands on the EMLS's current-carrying capacity, material properties, and physical performance, posing significant challenges to its launch efficiency, accuracy, and service life.

[0003] The contact performance between the guide rail and the armature is a key factor in the launch efficiency of the EMLS launch system. This is because maintaining good sliding electrical contact at the contact interface is extremely difficult in extreme multi-physics environments. Furthermore, during high-speed armature motion, the current flowing through the sliding electrical contact interface exhibits a velocity skin effect (VSE). This manifests as a high concentration of current at the contact interface, resulting in excessively high local current density peaks. This can lead to problems such as heat loss at the contact interface, electromagnetic interference, material damage, and physical damage.

[0004] During the high-speed relative motion of the armature and guide rail, VSE is inevitable and plays a decisive role in the current density distribution at the electrical contact interface. To effectively suppress VSE, reduce the peak current density at the contact interface, and mitigate the thermal effects of the EMLS system, a series of research projects have been proposed to address this challenge. These research approaches are primarily categorized into structural optimization and material design. Structural optimization design is particularly favored due to its short research cycle and relatively low computational effort.

[0005] Currently, there is still a lack of an effective method to quickly and accurately determine the guide rail structure that can effectively suppress VSE. Summary of the Invention

[0006] In view of this, the purpose of the present application is to provide a method, device, equipment and storage medium for determining the guide rail structure of an electromagnetic launch system, which can quickly and accurately determine the guide rail structure that can effectively suppress the VSE effect.

[0007] In a first aspect, the present application provides a method for determining a guide rail structure of an electromagnetic launch system, including:

[0008] Establishing a basic model of an electromagnetic launch system, wherein the basic model includes two parallel flat guide rails and an armature;

[0009] Modifying the basic model to obtain convex guide rail models with different structural parameters;

[0010] Conducting a power-on test on the convex guide rail models with different structural parameters to determine linear current density distribution information at the trailing edge of the contact interface of the convex guide rail models;

[0011] Based on the line current density distribution information, first structural information of the convex guide rail model is determined.

[0012] Optionally, before conducting the power-on test on the convex guide rail models with different structural parameters, the method further includes:

[0013] The convex guide rail model is simplified based on the velocity skin effect theory to obtain simplified convex guide rail models with different structural parameters;

[0014] Then, the power-on test is performed on the convex guide rail models with different structural parameters, including:

[0015] An electrical experiment was conducted on the simplified convex guide rail models with different structural parameters.

[0016] Optionally, the convex guide rail model includes any one or more of the following: an elliptical guide rail model, a trapezoidal guide rail model, and a rectangular guide rail model.

[0017] Optionally, the line current density distribution information includes: current density peak value and / or current density mean value;

[0018] The determining, based on the line current density distribution information, first structural information of the convex guide rail model includes:

[0019] Based on the current density peak value and / or the current density mean value, first structural information of the convex guide rail model is determined.

[0020] Optionally, the method further includes:

[0021] Establishing an electromagnetic-thermal coupling model of the convex guide rail model;

[0022] Determining temperature information of the convex guide rail model under the power-on test based on the electromagnetic-thermal coupling model;

[0023] Based on the line current density distribution information, the first structural information of the convex guide rail model is determined, including: based on the temperature information and the line current density distribution information, the first structural information of the convex guide rail model is determined.

[0024] In a second aspect, the present application provides a device for determining a guide rail structure of an electromagnetic launch system, characterized by comprising:

[0025] An establishing unit, configured to establish a basic model of an electromagnetic launch system, wherein the basic model includes two parallel flat guide rails and an armature;

[0026] A modification unit, used for modifying the basic model to obtain a convex guide rail model with different structural parameters;

[0027] a determination unit, configured to conduct a power-on experiment on the convex guide rail models with different structural parameters to determine linear current density distribution information at a trailing edge of a contact interface of the convex guide rail model;

[0028] The determining unit is further configured to determine first structural information of the convex guide rail model based on the line current density distribution information.

[0029] Optionally, the device further includes:

[0030] A simplification unit is used to simplify the convex guide rail model based on the velocity skin effect theory to obtain simplified convex guide rail models with different structural parameters;

[0031] The determining unit is specifically used to perform an electrical experiment on the simplified convex guide rail models with different structural parameters.

[0032] Optionally, the line current density distribution information includes: current density peak value and / or current density mean value;

[0033] The determining unit is specifically used to determine the first structural information of the convex guide rail model based on the current density peak value and / or the current density mean value.

[0034] In a third aspect, the present application provides a device for determining a guide rail structure of an electromagnetic launch system, comprising:

[0035] memory for storing computer programs;

[0036] A processor is used to execute the computer program stored in the memory to implement the steps of the method for determining the guide rail structure of the electromagnetic launch system as described in the first aspect.

[0037] In a fourth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon, and the computer program is executed by a processor to implement the steps of the method for determining the guide rail structure of the electromagnetic launch system as described in the first aspect.

[0038] As can be seen, the embodiments of the present application disclose a method, apparatus, device, and storage medium for determining the guide rail structure of an electromagnetic launch system. In this method, a basic model of the electromagnetic launch system is established, the basic model including two parallel flat guide rails and an armature. The basic model is modified to obtain convex guide rail models with different structural parameters. A power-on experiment is performed on the convex guide rail models with different structural parameters to determine the linear current density distribution information at the trailing edge of the contact interface of the convex guide rail model. Based on the linear current density distribution information, the first structural information of the convex guide rail model is determined. The above method can quickly and accurately determine the guide rail structure that can effectively suppress the VSE effect by using convex guide rail models with different structural parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0040] Figure 1 This is a flow chart of a method for determining a guide rail structure of an electromagnetic launch system provided in an embodiment of the present application;

[0041] Figure 2 This is a schematic diagram of the structure, mesh division, and geometric parameters of a basic model of an electromagnetic launch system provided in an embodiment of the present application;

[0042] Figure 3 This is a schematic diagram of an input pulse current waveform provided in an embodiment of the present application;

[0043] Figure 4 This is a structural diagram of a convex guide rail model provided in an embodiment of the present application;

[0044] Figure 5 This is a schematic diagram of the armature structure of an EMLS planar structure guide rail provided in an embodiment of the present application;

[0045] Figure 6 This is a schematic diagram of a VSE equivalent simplified model of EMLS provided in this application;

[0046] Figure 7 This is a schematic diagram comparing a current density distribution diagram obtained by VSE in a three-dimensional EMLS dynamic simulation model provided in an embodiment of the present application and a current density distribution diagram obtained based on a simplified model equivalent to VSE theory;

[0047] Figure 8This is a schematic diagram of the correspondence between the linear current density distribution information and the structural parameters at the trailing edge of the contact interface between the guide rail and the armature in a simplified convex guide rail model provided in an embodiment of the present application;

[0048] Figure 9 This is a schematic diagram comparing the peak current density and the mean current density at the trailing edge of the electrical contact interface between a convex guide rail and a flat guide rail provided in an embodiment of the present application;

[0049] Figure 10 1 is a comparative schematic diagram of the temperature rise caused by the thermal effect of current and frictional heat at the final moment of emission provided by an embodiment of the present application;

[0050] Figure 11 This is a structural schematic diagram of a guide rail structure determination device for an electromagnetic launch system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0051] To make the purpose, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application are within the scope of protection of this application.

[0052] To facilitate understanding of the technical solution provided by this application, the following will describe a method for determining the guide rail structure of an electromagnetic launch system provided by this application in conjunction with the accompanying drawings. Figure 1 , which is a flow chart of a method for determining a guide rail structure of an electromagnetic launch system provided in an embodiment of the present application, as shown in FIG. Figure 1 As shown, the method includes S101-S104.

[0053] S101: Establishing a basic model of an electromagnetic launch system, wherein the basic model includes two parallel flat guide rails and an armature.

[0054] In the embodiment of the present application, the specific parameters of the basic model of the electromagnetic launch system are not limited. As an example, Figure 2 As shown, Figure 2 This is a schematic diagram of the structure, mesh division and geometric parameters of a basic model of an electromagnetic launch system provided in an embodiment of the present application. Figure 2 (a) is a schematic diagram of the 3D structure of the basic model, and (b) is a schematic diagram of the mesh division. Figure 2(c) is a top view schematic diagram of the basic model. The basic model may include two parallel flat guide rails and an armature. The specific structure of the armature is not limited in this application. As an example, the armature may be a C-shaped armature. This application does not limit the geometric parameters of the basic model of EMLS. The width of the parallel flat guide rails may be 2000 mm, the thickness may be 20 mm, and the height may be 40 mm. The tail thickness of the armature is 3 mm, the width of the guide rail / armature contact interface is 25 mm, the armature neck radius is 17.5 mm, the armature neck width is 11 mm, the armature head thickness is 16 mm; and the guide rail spacing is 35 mm.

[0055] In the embodiment of the present application, the guide rail and the armature are made of copper and aluminum, respectively. The material properties of the basic model for establishing EMLS can be shown in Table 1 below.

[0056] Table 1

[0057]

[0058] S102: Modify the basic model to obtain convex guide rail models with different structural parameters.

[0059] In the embodiments of the present application, after obtaining a base model, modifications are made to the base model. As an example, two parallel flat guide rails are each convex inwardly convexed, i.e., modified in the Y-axis direction, to obtain convex guide rail models with different structural parameters. The present application does not limit the specific structure of the convex guide rail model, and the convex guide rail model includes any one or more of the following: an elliptical guide rail model, a trapezoidal guide rail model, and a rectangular guide rail model.

[0060] In the embodiment of the present application, a pulse current with a peak value of 700kA is applied, such as Figure 3 As shown, Figure 3 This is a schematic diagram of a pulse current waveform provided in an embodiment of the present application, wherein the horizontal axis represents time and the vertical axis represents input current.

[0061] As an example, Figure 4 As shown, Figure 4 A schematic structural diagram of a convex guide rail model provided in an embodiment of the present application. Figure 4 (a) and (d) represent the elliptical guide model. Figure 4 (b) and (e) represent the trapezoidal guide rail model. Figure 4(c) and (f) represent rectangular guide rail models. It is understood that the structural parameters of the elliptical guide rail model include a first length a and a guide rail protrusion height, and the first length can be the major axis radius a of the ellipse. The structural parameters of the trapezoidal guide rail model include a second length b, a third length Δb, and a guide rail protrusion height. The second length b can be half of the short side width, and the third length Δb can be the difference between half of the long side width of the trapezoid and half of the short side width of the trapezoid. The structural parameters of the rectangular guide rail model include a fourth length d and a guide rail protrusion height, and the fourth length d can be half of the long side width of the rectangle.

[0062] It is understandable that the present application only modifies the structural parameters of the basic model, keeping the material properties of EMLS unchanged. That is, for the elliptical guide rail model, the present application can flexibly set the first length a and the guide rail protrusion height to different values to obtain elliptical guide rail models with different structural parameters. For the trapezoidal guide rail model, the present application can flexibly set the second length b, the third length Δb and the guide rail protrusion height to obtain trapezoidal guide rail models with different structural parameters. For the rectangular guide rail model, the present application can flexibly set the fourth length d and the guide rail protrusion height to obtain rectangular guide rail models with different structural parameters.

[0063] This application does not limit the specific value of the guide rail protrusion height. The guide rail protrusion height can be constant at 10 mm or set to other values.

[0064] S103: Conducting a power-on experiment on the convex guide rail models with different structural parameters to determine linear current density distribution information at the trailing edge of the contact interface of the convex guide rail models.

[0065] It can be understood that after obtaining convex guide rail models with different structural parameters, the present application can conduct power-on experiments on convex guide rail models with different structural parameters. Specifically, the present application can pass terminal current on one side of the convex guide rail model and ground the same side of the other end of the guide rail to form a loop.

[0066] After power is turned on, the present application can scan and analyze the convex guide rail model with different structural parameters to determine the linear current density distribution information along the trailing edge of the contact interface. It can be understood that the contact interface refers to the part where the guide rail contacts the armature. Figure 4 The thin yellow line in the middle represents the trailing edge of the contact interface between the guide rail and the armature.

[0067] This application does not limit the specific content of the line current density distribution information. As an example, the line current density distribution information includes: current density peak value and / or current density mean value. It is understood that the current density peak value may be the maximum value of the current density, and the current density mean value indicates the average degree of the current density. The more average the current density, the lower the value of the current density mean value.

[0068] S104: Determine first structural information of the convex guide rail model based on the line current density distribution information.

[0069] This application does not limit the method of determining the first structural information of the convex guide rail model based on the line current density distribution information. When the line current density distribution information includes: a current density peak value and / or a current density mean value; determining the first structural information of the convex guide rail model based on the line current density distribution information includes: determining the first structural information of the convex guide rail model based on the current density peak value and / or the current density mean value.

[0070] It can be understood that the first structural information of the convex guide rail model is used to represent the structural parameters of the convex guide rail model that have the best effect in suppressing VSE. The present application can determine the structural parameters that make the convex guide rail model suppress VSE the best by comparing convex guide rail models with different structural parameters. As an example, the present application can use the structural parameters of the convex guide rail model with the lowest current density peak as the first structural information, and / or use the structural parameters of the convex guide rail model with the lowest current density mean as the first structural information. As another example, the present application can also determine the structural parameters that make the convex guide rail model suppress VSE the best based on the weight algorithm, combined with the current density peak and the current density mean.

[0071] As a possible implementation method, the present application can first determine the optimal structural parameters of each type of convex guide rail model, such as first determining the structural parameters with the best VSE suppression effect in the trapezoidal guide rail model, elliptical guide rail model and rectangular guide rail model, and then compare the structural parameters with the best VSE suppression effect in each type of convex guide rail model to determine the structural parameters that make the convex guide rail model have the best VSE suppression effect, which is the first structural information.

[0072] By using the above method, convex guide rail models with different structural parameters are constructed, and the current density distribution information at the trailing edge of the armature contact interface is compared with the convex guide rail model with different structural parameters. This can quickly and accurately determine the guide rail structure that can effectively suppress the VSE effect.

[0073] As a possible implementation, before conducting power-on tests on convex guide rail models with different structural parameters, the present application provides a method for determining the guide rail structure of an electromagnetic launch system, further comprising: simplifying the convex guide rail model based on velocity skin effect theory to obtain simplified convex guide rail models with different structural parameters. Conducting power-on tests on the convex guide rail models with different structural parameters includes conducting power-on tests on the simplified convex guide rail models with different structural parameters.

[0074] Understandably, the armature in an EMLS can accelerate to several thousand meters per second within milliseconds. This process generates relative motion between the electromagnetic field and the armature, creating a correction term in the electromagnetic field. This is influenced by the "Clustering of Small Sources" (CNSS) and "Clustering of Short Paths" (CASP), which can cause current VSE at the sliding electrical contact interface between the EMLS armature and the guide rail.

[0075] VSE refers to the phenomenon in which the current density in a high-speed moving conductor shifts due to the conductor's motion, causing the current to concentrate toward the trailing edge or a specific area of the conductor. In EMLS, VSE manifests as current concentration at the trailing edge of the contact interface between the high-speed moving armature and the stationary rail.

[0076] As the relative speed between the armature and rail increases, this current concentration intensifies at the contact interface and can lead to localized softening and melting of the armature. This not only compromises the structural integrity of the armature but also adversely affects the launch speed and efficiency of the EMLS. Therefore, VSE is considered an important factor in optimizing EMLS performance.

[0077] Assuming that the armature and the guide rail are in ideal contact condition (no resistance) during EMLS launch, when the current flows between the guide rail and the armature, the concentration degree of the current in different directions of the contact interface is expressed by the current concentration thickness δ in the guide rail. r , armature current concentration thickness δ a , and skin depth δ v Respectively expressed as:

[0078]

[0079] S=1.72-2.72δ a / d;(4)

[0080] where ρ r and ρ a They represent the resistivity of the guide rail and armature materials respectively, μ0 represents the vacuum permeability, μ0=4π×10 -7 N / A 2 (Newton / Ampere 2 ), θ represents the angle between the armature tail and the guide rail, v represents the armature movement speed, d represents the thickness of the armature tail, S represents the skin depth correction parameter, and β represents the depth ratio, which is expressed as:

[0081]

[0082] Under the determined EML structure, S is a constant value, usually 1, so the current concentration thickness δ in the rail r , armature current concentration thickness δ a , and skin depth δ v Approximately:

[0083]

[0084] like Figure 5 As shown, Figure 5 This is a schematic diagram of the armature structure of the guide rail in the EMLS planar structure provided in an embodiment of the present application, wherein Figure 5 (a) represents the 2D armature structure, Figure 5 (b) shows the 3D armature structure. Figure 5 Middle t a Indicates the thickness of the armature. The parameter size can be 8mm, h a Indicates the armature height, the parameter size can be 40mm, w a Indicates the armature width, the parameter size can be 40mm, t t Indicates the thickness of the armature tail, the parameter size can be 3mm, r n represents the armature neck radius, and the parameter size can be 10.6mm. θ represents the armature tail angle, and the parameter size can be 20°.

[0085] The material parameters in EMLS are shown in Table 1. In this application, it is assumed that the armature motion speed v = 300m / s. Substituting into formulas (6) to (8), we can get δ r =1mm,δ v =1mm. Based on this, the EMLS guide rail model is equivalently simplified to a thickness of 1mm (δ r ), 4mm wide (the width is determined to be 4mm based on the approximate calculation of the thickness of 1mm and the angle of 20°), and the width of the area where the equivalent simplified guide rail model makes electrical contact with the tail of the armature is 1mm (δ v ), the height remains unchanged at 40mm. In addition, to ensure the validity of the results, the pulse current is reduced to 70% of the original value, which is the result obtained under a large amount of calculation data. Figure 6 As shown, Figure 6 A schematic diagram of a VSE equivalent simplified model of an EMLS provided in this application, in which the red part is the equivalent simplified guide rail. This application does not limit the width to a specific value. It only needs to ensure that the width of the contact interface with the armature is 1mm. The width can be adjusted as needed, such as 2mm, 4mm, etc. It is worth noting that before the current flows through the guide rail / armature contact surface, it is mainly concentrated in the inner surface area of the two guide rails, and the closer to the tail of the armature, the higher the current concentration. The thickness of 1mm is an approximate value, and this assumption also helps to ensure the convergence of the model calculation.

[0086] Based on the above analysis, the present application can calculate the current density distribution diagram obtained by VSE in the three-dimensional EMLS dynamic simulation model based on the finite element model and compare it with the current density distribution diagram obtained based on the VSE theoretical equivalent simplified model, such as Figure 7 As shown, Figure 7 This is a schematic diagram comparing the current density distribution diagram obtained by VSE in a three-dimensional EMLS dynamic simulation model provided in an embodiment of the present application and the current density distribution diagram obtained based on a simplified model equivalent to VSE theory. Figure 7 (a) shows the current density distribution of the unsimplified rail structure showing the 3D morphology, Figure 7 (b) Current density distribution diagram of the simplified guide rail structure showing the 3D morphology, Figure 7 (c) shows the current density distribution of the unsimplified guide rail structure showing the 2D morphology, Figure 7 (d) Current density distribution diagram of the simplified 2D guide rail structure, where different colors represent the distribution of current density.

[0087] based on Figure 7 Comparative analysis shows that the VSE equivalent simplified model can effectively realize the effective representation of the current density distribution of the armature and sliding electrical contact interface of EMLS at a launch speed of 300m / s.

[0088] The peak current density at the trailing edge of the contact interface in the VSE equivalent simplified model is 1.57×10 10 A / m2, and the peak current density at the trailing edge of the contact interface at a launch speed of 300 m / s in the EMLS model is 1.64×10 10 The error in A / m2 is only 4.3%, but the calculation time is shortened by 75.6%. Therefore, this method significantly shortens the calculation time while maintaining the accuracy of the EMLS model.

[0089] In summary, this method performs equivalent simplification on the model of EMLS at a launch speed of 300m / s based on the VSE theory. After the simplification, the calculation time of the model is shortened by 75.6%, and the error is only 4.3%. In the embodiment of the present application, a power-on experiment is performed based on the simplified convex guide rail model, so that the linear current density distribution information of the trailing edge of the contact interface of the simplified convex guide rail model can be obtained. Based on the simplified model, the first structural information of the convex guide rail model can be quickly and effectively determined. Compared with ordinary three-dimensional transient studies, the equivalent simplified three-dimensional finite element model of the guide rail structure based on the VSE theory can effectively reduce computing resources and save computing time.

[0090] In the embodiment of the present application, the linear current density distribution information is determined based on the simplified convex rail model. Figure 8 , Figure 8 A schematic diagram of the correspondence between the linear current density distribution information and the structural parameters at the trailing edge of the contact interface between the guide rail and the armature in a simplified convex guide rail model provided in an embodiment of the present application. Figure 8The following description will be made by taking the guide rail raised height of 10mm as an example, and the subsequent description will not be repeated. Figure 8 As shown, Figure 8 (a) shows the relationship between the current density at the trailing edge of the guide rail-armature contact interface and the first length a. As a increases, the arc length of the trailing edge of the contact interface decreases, and the concentration area of J (current density) also shifts, moving away from the midpoint of the trailing edge, resulting in a more uniform distribution and a smaller peak current density. Therefore, when the guide rail protrusion height is 10 mm, the optimal structure for the elliptical guide rail is when a = 14 mm. Figure 8 (b) shows that there are two prominent current density concentration points at the rear edge of the rectangular guide rail contact interface, and as d increases, the J concentration point spreads to both sides. By comparison, it is found that when d = 12 mm, the current density peak value J max The structure is optimal at this time. Figure 8 (c)-(f) show the change of J distribution along the trailing edge of the contact interface with the second length b when the third length Δb=2mm, Δb=3mm, Δb=4mm, Δb=5mm in the trapezoidal guide rail respectively. When Δb=2mm, there are two obvious J concentration points along the trailing edge of the contact interface. When 3mm≤Δb≤5mm, there are four J concentration points along the trailing edge of the contact interface (two in the middle and two at both ends). When Δb=2mm, b=10mm, the current density peak J max Minimum, at this time the trapezoidal guide rail structure is optimal.

[0091] Figure 9 A schematic diagram comparing the peak current density and the mean current density at the trailing edge of the electrical contact interface between a convex guide rail and a flat guide rail provided in an embodiment of the present application. Figure 9 The convex guide rail in the figure is a simplified convex guide rail model. Figure 9 It can be clearly seen that compared with the flat guide rail, the J max and J ave Therefore, the convex guide rail has a significant positive effect on suppressing VSE. max The minimum is 3.11×10 10 A / m 2 , which is 26.5% lower than the flat guide rail and 1.12×10 smaller than the elliptical guide rail. 10 A / m 2 , 0.13×10 smaller than the rectangular guide rail 10 A / m 2 ; Trapezoidal guide rail J ave 35.4% lower than a flat guide rail and 0.46×10 smaller than an elliptical guide rail 10 A / m 2 , 0.12×10 larger than the rectangular rail 10 A / m2 In summary, convex guide rails have obvious advantages over flat guide rails in alleviating VSE, among which trapezoidal guide rails have more obvious advantages over elliptical guide rails and rectangular guide rails. However, there are still two obvious current density concentration points at the tips of the protruding parts of the guide rail structure.

[0092] As a possible implementation, the present application provides a method for determining a guide rail structure of an electromagnetic launch system, further comprising the following steps:

[0093] A1: Establish an electromagnetic-thermal coupling model of the convex guide rail model.

[0094] A2: Based on the electromagnetic-thermal coupling model, determine the temperature information of the convex guide rail model in the power-on experiment.

[0095] In an embodiment of the present application, an electromagnetic-thermal coupling model of the convex guide rail model can be established based on a three-dimensional finite element analysis model software. The present application does not limit the specific method of establishing the electromagnetic-thermal coupling model. As an example, the present application can establish the electromagnetic-thermal coupling model using the following formula:

[0096]

[0097] In formula (4), F represents the electromagnetic force on the armature, L' r is the inductance gradient, and i is the input pulse current. It is understood that the EMLS launch time is a few milliseconds, during which the current density varies with time. Equation (9) is used to calculate the electromagnetic force exerted on the armature during railgun launch. Given the armature mass, the armature launch velocity v can be calculated from the electromagnetic force.

[0098] In formula (5), T is the temperature of the convex guide rail model, μ f is the sliding friction coefficient of the contact interface, F N is the pressure at the contact interface, c is the specific heat capacity, ρ m represents the material density, is the rate of change of temperature with time, which represents the time derivative of temperature; κ is the heat transfer coefficient, is a vector differential operator, and J represents the linear current density distribution information. The left side of formula (10) represents the accumulation of heat. The first term on the right side represents the heat transferred by heat conduction, the second term represents Joule heat, and the third term represents friction heat.

[0099] According to the above records, the armature launch speed of the simplified model can be v = 300m / s. When the armature launch speed v = 300m / s, the sliding electrical contact interface is dry friction, so μ f= 0.15. To ensure good electrical contact, the contact pressure on the contact surface is estimated to be 80 MPa based on Marshall's "gram / ampere rule." To accurately compare the effects of the three structures on the temperature field, heat dissipation factors such as natural and forced convection during EMLS launch, as well as surface radiation to the environment, are ignored. That is, the coupling between the temperature field and the fluid field is not considered.

[0100] It can be understood that the temperature information can be the temperature information at the last moment of EMLS transmission.

[0101] Then S104 determines the first structural information of the convex guide rail model based on the line current density distribution information, including: determining the first structural information of the convex guide rail model based on the temperature information and the line current density distribution information.

[0102] It is understood that the present application can combine temperature information and line current density distribution information to determine the first structural information of the convex guide rail model. As an example, the present application can use a weighted algorithm to combine temperature information and line current density distribution information to determine the structural parameters that optimize the convex guide rail model's VSE suppression effect. By combining temperature information, the guide rail structure that effectively suppresses the VSE effect can be more accurately determined.

[0103] The following is a further explanation of this application in conjunction with specific experimental information, see Figure 10 , Figure 10 This diagram compares the temperature rise caused by the current thermal effect and frictional heating at the final moment of launch, demonstrating that frictional heat at the contact interface is the primary influencing factor. Compared to a planar guideway, the current thermal effect of the trapezoidal convex guideway remains essentially unchanged, while the current thermal effect of the elliptical and rectangular convex guideways increases. The convex guideway generates less frictional heat than the planar guideway. Overall, the trapezoidal guideway exhibits the best contact interface thermal effect.

[0104] In summary, compared with flat guide rails, convex guide rails will cause the J of the armature to max and temperature increased, especially the elliptical guide J max The worst case, but this does not lead to a decrease in the contact interface temperature and the armature J ave The excessive increase in VSE indicates that convex guideways have positive effects in suppressing VSE and reducing the thermal effects of the launch system. Compared with convex guideways, trapezoidal convex guideways performed best in many aspects of the study, indicating that trapezoidal guideways have advantages over elliptical and rectangular guideways in suppressing VSE and reducing the thermal effects of the launch system.

[0105] The following introduces a device for determining the guide rail structure of an electromagnetic launch system provided in an embodiment of the present application. The device described below and the method for determining the guide rail structure of an electromagnetic launch system described above can be referenced to each other.

[0106] See also Figure 11 , Figure 11 A schematic structural diagram of a device for determining a guide rail structure of an electromagnetic launch system provided in an embodiment of the present application, wherein the device includes an establishing unit 201, a modifying unit 202, and a determining unit 203.

[0107] An establishing unit 201 is used to establish a basic model of an electromagnetic launch system, wherein the basic model includes two parallel flat guide rails and an armature;

[0108] A modification unit 202 is used to modify the basic model to obtain a convex guide rail model with different structural parameters;

[0109] a determination unit 203 configured to conduct a power-on test on the convex guide rail models with different structural parameters to determine linear current density distribution information at a trailing edge of a contact interface of the convex guide rail model;

[0110] The determining unit 203 is further configured to determine first structural information of the convex guide rail model based on the line current density distribution information.

[0111] As a possible implementation, the device further includes:

[0112] A simplification unit is used to simplify the convex guide rail model based on the velocity skin effect theory to obtain simplified convex guide rail models with different structural parameters;

[0113] The determining unit is specifically used to perform an electrical experiment on the simplified convex guide rail models with different structural parameters.

[0114] As a possible implementation, the line current density distribution information includes: a current density peak value and / or a current density mean value;

[0115] The determining unit is specifically used to determine the first structural information of the convex guide rail model based on the current density peak value and / or the current density mean value.

[0116] As a possible implementation manner, the convex guide rail model includes any one or more of the following: an elliptical guide rail model, a trapezoidal guide rail model, and a rectangular guide rail model.

[0117] As a possible implementation, the device further includes:

[0118] An establishing unit, used for establishing an electromagnetic-thermal coupling model of the convex guide rail model;

[0119] The determining unit 203 is further configured to determine temperature information of the convex guide rail model under the power-on test based on the electromagnetic-thermal coupling model;

[0120] The determining unit is specifically used to determine the first structural information of the convex guide rail model based on the temperature information and the line current density distribution information.

[0121] It should be noted that the guide rail structure determination device of the electromagnetic launch system provided in the embodiment of the present application has the technical effects of any of the above embodiments, and the embodiment of the present application will not be described in detail here.

[0122] The present application also provides a device for determining the guide rail structure of an electromagnetic launch system, which may include a memory and a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for determining the guide rail structure of the electromagnetic launch system as described in the above embodiment is implemented.

[0123] It should be noted that the guide rail structure determination device of the electromagnetic launch system provided in the embodiment of the present application has the technical effects of any of the above embodiments, and the embodiment of the present application will not be described in detail here.

[0124] The present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed, can implement the steps provided in the above embodiments. The storage medium may include: a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, among other media capable of storing program code.

[0125] It should be noted that the computer-readable storage medium provided in the embodiment of the present application has the technical effects of any of the above embodiments, and the embodiments of the present application are not described in detail here.

[0126] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0127] It should also be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the element.

[0128] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above examples is only intended to help understand the method and core ideas of this application. It should be noted that for those skilled in the art, without departing from the principles of this application, various improvements and modifications can be made to this application, and such improvements and modifications also fall within the scope of protection of the claims of this application.

Claims

1. A method for determining the guide rail structure of an electromagnetic launch system, characterized in that: include: Establishing a basic model of an electromagnetic launch system, wherein the basic model includes two parallel flat guide rails and an armature; Modifying the basic model to obtain convex guide rail models with different structural parameters; Conducting a power-on test on the convex guide rail models with different structural parameters to determine linear current density distribution information at the trailing edge of the contact interface of the convex guide rail models; Based on the line current density distribution information, first structural information of the convex guide rail model is determined.

2. The method according to claim 1, characterized in that Before conducting the power-on test on the convex guide rail models with different structural parameters, the method further includes: The convex guide rail model is simplified based on the velocity skin effect theory to obtain simplified convex guide rail models with different structural parameters; Then, the power-on test is performed on the convex guide rail models with different structural parameters, including: An electrical experiment was conducted on the simplified convex guide rail models with different structural parameters.

3. The method according to claim 1, characterized in that The convex guide rail model includes any one or more of the following: an elliptical guide rail model, a trapezoidal guide rail model and a rectangular guide rail model.

4. The method according to claim 1, wherein The line current density distribution information includes: current density peak value and / or current density mean value; The determining, based on the line current density distribution information, first structural information of the convex guide rail model includes: Based on the current density peak value and / or the current density mean value, first structural information of the convex guide rail model is determined.

5. The method according to claim 1, wherein The method further comprises: Establishing an electromagnetic-thermal coupling model of the convex guide rail model; determining temperature information of the convex guide rail model under the power-on test based on the electromagnetic-thermal coupling model; Based on the line current density distribution information, the first structural information of the convex guide rail model is determined, including: based on the temperature information and the line current density distribution information, the first structural information of the convex guide rail model is determined.

6. A device for determining the guide rail structure of an electromagnetic launch system, characterized in that: include: An establishing unit, configured to establish a basic model of an electromagnetic launch system, wherein the basic model includes two parallel flat guide rails and an armature; A modification unit, used for modifying the basic model to obtain a convex guide rail model with different structural parameters; a determination unit, configured to conduct a power-on experiment on the convex guide rail models with different structural parameters to determine linear current density distribution information at a trailing edge of a contact interface of the convex guide rail model; The determining unit is further configured to determine first structural information of the convex guide rail model based on the line current density distribution information.

7. The device according to claim 6, characterized in that The device further comprises: A simplification unit is used to simplify the convex guide rail model based on the velocity skin effect theory to obtain simplified convex guide rail models with different structural parameters; The determining unit is specifically used to perform an electrical experiment on the simplified convex guide rail models with different structural parameters.

8. The device according to claim 6, characterized in that The line current density distribution information includes: current density peak value and / or current density mean value; The determining unit is specifically used to determine the first structural information of the convex guide rail model based on the current density peak value and / or the current density mean value.

9. A device for determining the guide rail structure of an electromagnetic launch system, characterized in that: include: memory for storing computer programs; A processor, configured to execute the computer program stored in the memory to implement the steps of the method for determining the guide rail structure of the electromagnetic launch system according to any one of claims 1 to 5.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: The computer program is executed by a processor to implement the steps of the method for determining the guide rail structure of an electromagnetic launch system according to any one of claims 1 to 5.

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