Wheel-rail local contact information acquisition method and device

Abstract

The application provides a wheel-rail local contact information acquisition method and device, and relates to the technical field of locomotive vehicle safety monitoring. The method comprises the following steps: performing normal contact analysis and calculation according to the wheel-rail contact geometric relationship to obtain wheel-rail normal force calculation results, and updating the wheel-rail normal force calculation results according to the comparison result between the wheel-rail normal force calculation results and the measured wheel-rail normal force to obtain wheel-rail normal force updated calculation results; performing tangential contact analysis and calculation according to the wheel-rail friction coefficient and the wheel-rail normal force updated calculation results to obtain wheel-rail tangential force calculation results, updating the wheel-rail tangential force calculation results according to the comparison result between the wheel-rail tangential force calculation results and the measured wheel-rail tangential force, and determining the wheel-rail local contact information according to the wheel-rail tangential force updated calculation results. The method and device provided in the application can improve the wheel-rail local contact information acquisition accuracy.

Description

Technical Field

[0001] This invention relates to the field of locomotive and rolling stock safety monitoring technology, specifically to a method and device for acquiring wheel-rail partial contact information. Background Technology

[0002] Local wheel-rail contact information is a key parameter for predicting wheel-rail wear and rolling contact fatigue, among other wheel-rail interface degradation. This information needs to be obtained based on given wheel-rail relative motion information. However, direct testing of wheel-rail relative motion information is difficult, and it often relies on numerical simulations of vehicle dynamics. Since the vehicle dynamics simulation model itself has significant calculation errors, this affects the accuracy of the local wheel-rail contact information solution.

[0003] Force-measuring wheelsets are a primary technical means for conducting on-board wheel-rail force measurement and vehicle operation safety assessment. Existing force-measuring wheelsets can accurately measure and obtain the resultant wheel-rail force and wheel-rail contact area, but they cannot obtain information on the relative motion between the wheel and rail. Summary of the Invention

[0004] To address the problems in the prior art, embodiments of the present invention provide a method and apparatus for obtaining wheel-rail local contact information, which can at least partially solve the problems existing in the prior art.

[0005] On one hand, this invention proposes a method for obtaining wheel-rail local contact information, including:

[0006] Based on the correspondence, determine the lateral displacement of the wheelset, the rail irregularity, and the rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset;

[0007] The correspondence is the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail unevenness, and the preset rail gauge.

[0008] The wheel-rail contact geometry is determined based on the wheel-rail profile, wheelset lateral displacement and track irregularity, and rail gauge. The measured wheel-rail normal force and measured wheel-rail tangential force are obtained based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset.

[0009] Based on the stated wheel-rail contact geometry, a normal contact analysis calculation is performed to obtain the wheel-rail normal force calculation result. The wheel-rail normal force calculation result is then updated based on the comparison between the stated wheel-rail normal force calculation result and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result.

[0010] Tangential contact analysis is performed based on the wheel-rail friction coefficient and the updated calculation results of the wheel-rail normal force to obtain the wheel-rail tangential force calculation results. The wheel-rail tangential force calculation results are then updated based on the comparison between the wheel-rail tangential force calculation results and the measured wheel-rail tangential force. Based on the updated wheel-rail tangential force calculation results, the local wheel-rail contact information is determined.

[0011] The wheel-rail contact geometry includes the wheel-rail normal clearance and the contact plane; correspondingly, determining the wheel-rail contact geometry based on the wheel-rail profile, wheelset lateral displacement and rail irregularity, and rail gauge includes:

[0012] The positions of the wheel profile and rail profile in three-dimensional space are determined based on the wheel-rail profile, wheelset lateral displacement and rail irregularity, and rail gauge.

[0013] The wheel-rail normal clearance and the position of the contact origin are obtained when the wheel and rail are initially in contact and have not deformed, based on the positions of the wheel profile and rail profile in three-dimensional space.

[0014] The contact plane is determined based on the location of the contact origin.

[0015] The step of obtaining the measured wheel-rail normal force and measured wheel-rail tangential force based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset includes:

[0016] The wheel-rail coordinate system direction is determined based on the wheel-rail contact geometry. The wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset are then transformed according to the wheel-rail coordinate system direction to obtain the measured wheel-rail normal force and the measured wheel-rail tangential force.

[0017] The step of performing normal contact analysis calculations based on the wheel-rail contact geometry to obtain the wheel-rail normal force calculation results includes:

[0018] The maximum wheel-rail compression is determined as the initial condition for iteration, and the relative wheel-rail compression is obtained by superimposing the wheel-rail normal clearance.

[0019] Based on the relative compression of the wheel and rail, normal contact calculation is performed to obtain the wheel-rail contact patch area and the wheel-rail normal pressure.

[0020] The wheel-rail normal pressure is integrated within the wheel-rail contact patch area to obtain the wheel-rail normal force calculation result.

[0021] The step of performing tangential contact analysis calculations based on the wheel-rail friction coefficient and the updated wheel-rail normal force calculation results to obtain the wheel-rail tangential force calculation results includes:

[0022] The longitudinal and lateral creep rates of the wheel and rail are determined as the initial conditions for iteration. Based on the pre-acquired wheel and rail spin creep rate, the longitudinal creep rate, the lateral creep rate, the wheel and rail friction coefficient, and the wheel and rail normal force, the calculation results are updated and superimposed to obtain the wheel and rail tangential stress under the current working condition.

[0023] The wheel-rail tangential stress is integrated within the pre-obtained wheel-rail contact patch area to obtain the wheel-rail tangential force calculation result.

[0024] The wheel-rail tangential force calculation result includes the longitudinal creep force calculation result and the lateral creep force calculation result of the wheel and rail, and the measured wheel-rail tangential force includes the longitudinal creep force and the lateral creep force of the wheel and rail; correspondingly, updating the wheel-rail tangential force calculation result based on the comparison result between the wheel-rail tangential force calculation result and the measured wheel-rail tangential force includes:

[0025] If it is determined that the comparison result between the longitudinal creep force calculation result and the longitudinal creep force, and the comparison result between the lateral creep force calculation result and the lateral creep force are both less than a preset difference, then the wheel-rail tangential force calculation result at this time is determined as the wheel-rail tangential force update calculation result.

[0026] If at least one comparison result is determined to be greater than or equal to the preset difference, then the step of updating the wheel-rail tangential force calculation result continues.

[0027] On one hand, the present invention proposes a wheel-rail partial contact information acquisition device comprising:

[0028] The determining unit is used to determine the lateral displacement of the wheelset, the track irregularity, and the rail gauge corresponding to the position of the wheel-rail contact point of the force-measuring wheelset, based on the correspondence relationship.

[0029] The correspondence is the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail unevenness, and the preset rail gauge.

[0030] The acquisition unit is used to determine the wheel-rail contact geometry based on the wheel-rail profile, wheelset lateral displacement and rail irregularity, and rail gauge, and to acquire the measured wheel-rail normal force and measured wheel-rail tangential force based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force and wheel-rail longitudinal force of the force-measuring wheelset;

[0031] The first calculation unit is used to perform normal contact analysis calculation based on the wheel-rail contact geometry to obtain the wheel-rail normal force calculation result, and update the wheel-rail normal force calculation result based on the comparison result between the wheel-rail normal force calculation result and the measured wheel-rail normal force to obtain the updated wheel-rail normal force calculation result.

[0032] The second calculation unit is used to perform tangential contact analysis calculation based on the wheel-rail friction coefficient and the updated calculation result of the wheel-rail normal force to obtain the wheel-rail tangential force calculation result, update the wheel-rail tangential force calculation result based on the comparison result between the wheel-rail tangential force calculation result and the measured wheel-rail tangential force, and determine the wheel-rail local contact information based on the updated wheel-rail tangential force calculation result.

[0033] In another aspect, embodiments of the present invention provide a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the following method:

[0034] Based on the correspondence, determine the lateral displacement of the wheelset, the rail irregularity, and the rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset;

[0035] The correspondence is the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail unevenness, and the preset rail gauge.

[0036] The wheel-rail contact geometry is determined based on the wheel-rail profile, wheelset lateral displacement and track irregularity, and rail gauge. The measured wheel-rail normal force and measured wheel-rail tangential force are obtained based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset.

[0037] Based on the stated wheel-rail contact geometry, a normal contact analysis calculation is performed to obtain the wheel-rail normal force calculation result. The wheel-rail normal force calculation result is then updated based on the comparison between the stated wheel-rail normal force calculation result and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result.

[0038] Tangential contact analysis is performed based on the wheel-rail friction coefficient and the updated calculation results of the wheel-rail normal force to obtain the wheel-rail tangential force calculation results. The wheel-rail tangential force calculation results are then updated based on the comparison between the wheel-rail tangential force calculation results and the measured wheel-rail tangential force. Based on the updated wheel-rail tangential force calculation results, the local wheel-rail contact information is determined.

[0039] This invention provides a computer-readable storage medium, comprising:

[0040] The computer-readable storage medium stores a computer program that, when executed by a processor, implements the following method:

[0041] Based on the correspondence, determine the lateral displacement of the wheelset, the rail irregularity, and the rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset;

[0042] The correspondence is the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail unevenness, and the preset rail gauge.

[0043] The wheel-rail contact geometry is determined based on the wheel-rail profile, wheelset lateral displacement and track irregularity, and rail gauge. The measured wheel-rail normal force and measured wheel-rail tangential force are obtained based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset.

[0044] Based on the stated wheel-rail contact geometry, a normal contact analysis calculation is performed to obtain the wheel-rail normal force calculation result. The wheel-rail normal force calculation result is then updated based on the comparison between the stated wheel-rail normal force calculation result and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result.

[0045] Tangential contact analysis is performed based on the wheel-rail friction coefficient and the updated calculation results of the wheel-rail normal force to obtain the wheel-rail tangential force calculation results. The wheel-rail tangential force calculation results are then updated based on the comparison between the wheel-rail tangential force calculation results and the measured wheel-rail tangential force. Based on the updated wheel-rail tangential force calculation results, the local wheel-rail contact information is determined.

[0046] This invention also provides a computer program product, which includes a computer program that, when executed by a processor, implements the following method:

[0047] Based on the correspondence, determine the lateral displacement of the wheelset, the rail irregularity, and the rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset;

[0048] The correspondence is the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail unevenness, and the preset rail gauge.

[0049] The wheel-rail contact geometry is determined based on the wheel-rail profile, wheelset lateral displacement and track irregularity, and rail gauge. The measured wheel-rail normal force and measured wheel-rail tangential force are obtained based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset.

[0050] Based on the stated wheel-rail contact geometry, a normal contact analysis calculation is performed to obtain the wheel-rail normal force calculation result. The wheel-rail normal force calculation result is then updated based on the comparison between the stated wheel-rail normal force calculation result and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result.

[0051] Tangential contact analysis is performed based on the wheel-rail friction coefficient and the updated calculation results of the wheel-rail normal force to obtain the wheel-rail tangential force calculation results. The wheel-rail tangential force calculation results are then updated based on the comparison between the wheel-rail tangential force calculation results and the measured wheel-rail tangential force. Based on the updated wheel-rail tangential force calculation results, the local wheel-rail contact information is determined.

[0052] The wheel-rail partial contact information acquisition method and apparatus provided in this invention determine the wheelset lateral displacement, rail irregularity, and rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset based on a correspondence relationship. The correspondence relationship is a relationship between a preset wheel-rail contact point position, a preset wheelset lateral displacement and rail irregularity, and a preset rail gauge. The wheel-rail contact geometry is determined based on the wheel-rail profile, the wheelset lateral displacement and rail irregularity, and the rail gauge. The measured wheel-rail normal force and measured wheel-rail tangential force are obtained based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset. The process is then performed based on the wheel-rail contact geometry. Normal contact analysis is performed to calculate the wheel-rail normal force. The wheel-rail normal force calculation is then updated based on a comparison between the calculated wheel-rail normal force and the measured wheel-rail normal force. Tangential contact analysis is then performed based on the wheel-rail friction coefficient and the updated wheel-rail normal force calculation to calculate the wheel-rail tangential force. This tangential force calculation is then updated based on a comparison between the calculated wheel-rail tangential force and the measured wheel-rail tangential force. The updated wheel-rail tangential force calculation determines the local wheel-rail contact information, improving the accuracy of acquiring local wheel-rail contact information and providing a basis for assessing wheel-rail interface degradation. Attached Figure Description

[0053] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0054] Figure 1 This is a flowchart illustrating a method for obtaining wheel-rail local contact information according to an embodiment of the present invention.

[0055] Figure 2 This is a flowchart illustrating a method for obtaining wheel-rail local contact information according to another embodiment of the present invention.

[0056] Figure 3 This is a schematic diagram illustrating the three-dimensional distribution of the wheel-rail normal clearance provided in an embodiment of the present invention.

[0057] Figure 4 This is a schematic diagram illustrating the local contact distribution in the wheel-rail normal direction provided in an embodiment of the present invention.

[0058] Figure 5 This is a schematic diagram illustrating the local contact distribution of the wheel and rail tangential direction provided in an embodiment of the present invention.

[0059] Figure 6 This is a schematic diagram of the structure of a wheel-rail partial contact information acquisition device provided in an embodiment of the present invention.

[0060] Figure 7 This is a schematic diagram of the physical structure of a computer device provided in an embodiment of the present invention. Detailed Implementation

[0061] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Here, the illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be arbitrarily combined with each other.

[0062] Figure 1 This is a flowchart illustrating a method for obtaining partial wheel-rail contact information according to an embodiment of the present invention, as shown below. Figure 1 As shown, the wheel-rail local contact information acquisition method provided in this embodiment of the invention includes:

[0063] Step S1: Determine the lateral displacement of the wheelset, the rail irregularity, and the rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset based on the corresponding relationship.

[0064] The correspondence is the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and track unevenness, and the preset rail gauge.

[0065] Step S2: Determine the wheel-rail contact geometry based on the wheel-rail profile, wheelset lateral displacement and track unevenness, and rail gauge. Obtain the measured wheel-rail normal force and measured wheel-rail tangential force based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset.

[0066] Step S3: Perform normal contact analysis calculation based on the wheel-rail contact geometry to obtain the wheel-rail normal force calculation result, and update the wheel-rail normal force calculation result based on the comparison between the wheel-rail normal force calculation result and the measured wheel-rail normal force to obtain the updated wheel-rail normal force calculation result.

[0067] Step S4: Perform tangential contact analysis calculation based on the wheel-rail friction coefficient and the updated wheel-rail normal force calculation results to obtain the wheel-rail tangential force calculation results. Update the wheel-rail tangential force calculation results based on the comparison between the wheel-rail tangential force calculation results and the measured wheel-rail tangential force. Determine the wheel-rail local contact information based on the updated wheel-rail tangential force calculation results.

[0068] In step S1 above, the device determines the lateral displacement of the wheelset, the rail unevenness, and the rail gauge corresponding to the wheel-rail contact point position of the force measuring wheelset according to the correspondence relationship.

[0069] The correspondence refers to the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail misalignment, and the preset rail gauge. The device can be a computer that executes this method. The acquisition, storage, use, and processing of data in this application's technical solution all comply with relevant regulations. The correspondence can be represented by Table 1:

[0070] Table 1

[0071]

[0072]

[0073] The contents of Table 1 are further explained as follows: Calculation conditions: wheel LMA, rail 60.

[0074] The following explains how the correspondence shown in Table 1 was obtained:

[0075] The input parameters derived from the local wheel-rail contact information obtained by the force-measuring wheelset test include wheel-rail longitudinal force, wheel-rail lateral force, and wheel-rail vertical force; at the same time, the measured wheel-rail profile and wheel-rail material constants are input; and the wheel-rail friction coefficient is input according to the climatic conditions.

[0076] For the wheel-rail profile to be analyzed, without considering the wheelset roll angle, a two-dimensional wheel-rail normal contact analysis is conducted. First, assuming the wheelset roll angle is zero, the two-dimensional normal clearance between the left and right wheelsets is determined based on the wheelset lateral displacement, rail irregularity, and rail gauge. By adjusting the wheelset roll angle, the minimum normal clearance between the left and right wheelsets is made equal, thus determining the roll angle under specific wheelset lateral displacement, rail irregularity, and rail gauge conditions. The positions corresponding to the minimum normal clearance between the left and right wheelsets calculated using this roll angle are the left and right wheel-rail contact points. A reasonable range of variation for the wheelset lateral displacement, rail irregularity, and rail gauge is determined. Within this range, the positions of the left and right wheel-rail contact points on the wheels, calculated based on the above wheel-rail contact geometry, are obtained for different wheelset lateral displacements, rail irregularities, and rail gauges. A table showing the relationship between the contact point positions and the wheelset lateral displacement, rail irregularity, and rail gauge is generated, as shown in Table 1.

[0077] like Figure 2 As shown, based on the positions of the left and right wheel-rail contact points obtained from the force-measuring wheelset test, the relative motion attitude of the wheel and rail is obtained by referring to Table 1, namely the lateral displacement of the wheelset, the rail unevenness and the rail gauge.

[0078] In step S2 above, the device determines the wheel-rail contact geometry based on the wheel-rail profile, wheelset lateral displacement and rail irregularity, and rail gauge. It then obtains the measured wheel-rail normal force and measured wheel-rail tangential force based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset. The wheel-rail contact geometry includes the wheel-rail normal clearance and the contact plane. Correspondingly, determining the wheel-rail contact geometry based on the wheel-rail profile, wheelset lateral displacement and rail irregularity, and rail gauge includes:

[0079] The positions of the wheel profile and rail profile in three-dimensional space are determined based on the wheel-rail profile, wheelset lateral displacement and rail irregularity, and rail gauge.

[0080] The wheel-rail normal clearance and the position of the contact origin are obtained when the wheel and rail are initially in contact and have not deformed, based on the positions of the wheel profile and rail profile in three-dimensional space.

[0081] The contact plane is determined based on the location of the contact origin.

[0082] Based on the wheel-rail profile and the wheelset lateral displacement, rail irregularity, and rail gauge obtained through reverse calculation, the positions of the wheel and rail profiles in three-dimensional space are determined, and then the wheel-rail normal clearance at the initial contact point before deformation is calculated (e.g., ...). Figure 3 (As shown) and the location of the contact origin. For Figure 3 Further explanation is as follows:

[0083] Calculation conditions: Wheel LMA, rail 60, wheelset lateral movement 0 mm, yaw rate 0 rad.

[0084] The process of obtaining the measured wheel-rail normal force and measured wheel-rail tangential force based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset includes:

[0085] The wheel-rail coordinate system orientation is determined based on the wheel-rail contact geometry. The wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset are then transformed according to this orientation to obtain the measured wheel-rail normal force and the measured wheel-rail tangential force. The contact plane is determined based on the contact origin position, and the wheel-rail coordinate system orientation is further determined. The wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force obtained from the force-measuring wheelset test are transformed into contact patch coordinates for wheel-rail contact analysis to obtain the wheel-rail normal force and wheel-rail tangential force (longitudinal creep force / lateral creep force).

[0086] In step S3 above, the device performs normal contact analysis calculations based on the wheel-rail contact geometry to obtain the wheel-rail normal force calculation result, and updates the wheel-rail normal force calculation result based on the comparison between the wheel-rail normal force calculation result and the measured wheel-rail normal force, thus obtaining the updated wheel-rail normal force calculation result. The step of performing normal contact analysis calculations based on the wheel-rail contact geometry to obtain the wheel-rail normal force calculation result includes:

[0087] The maximum wheel-rail compression is determined as the initial condition for iteration, and the relative wheel-rail compression is obtained by superimposing the wheel-rail normal clearance.

[0088] Based on the relative compression of the wheel and rail, normal contact calculation is performed to obtain the wheel-rail contact patch area and the wheel-rail normal pressure.

[0089] The wheel-rail normal pressure is integrated within the wheel-rail contact patch area to obtain the wheel-rail normal force calculation result.

[0090] The Kalker variational method and Newton-Raphson iterative method are combined to solve for the local information of wheel-rail contact in the normal direction. The following steps are followed:

[0091] R1: Assuming a relatively large maximum wheel-rail compression as the initial condition for iteration, the wheel-rail normal clearance is superimposed to obtain the three-dimensional distribution of the relative wheel-rail compression, and then the relative wheel-rail compression is determined.

[0092] R2: Based on the relative compression between the wheel and rail, the NORM algorithm in the Kalker variational method is used to solve for the wheel-rail normal contact, obtaining the wheel-rail contact patch area and the wheel-rail normal pressure (e.g., Figure 4 As shown), the rail normal force is calculated by integrating the wheel-rail normal pressure over the contact patch region; for Figure 4 Further explanation: Calculation conditions: wheel LMA, rail 60, wheelset lateral displacement 0mm, yaw rate 0 rad, normal force N=73.4 kN, color indicates wheel-rail normal stress.

[0093] R3: Determine whether the difference between the calculated rail normal force from R2 and the inverse wheel-rail normal force is less than the convergence condition. If not, use the Newton-Raphson iteration to update the maximum wheel-rail compression and proceed to the next iteration. If yes, terminate the iteration, complete the normal contact calculation, and obtain the updated wheel-rail normal force calculation result.

[0094] In step S4 above, the device performs tangential contact analysis calculation based on the wheel-rail friction coefficient and the updated calculation result of the wheel-rail normal force to obtain the wheel-rail tangential force calculation result. The device then updates the wheel-rail tangential force calculation result based on the comparison between the wheel-rail tangential force calculation result and the measured wheel-rail tangential force, and determines the wheel-rail local contact information based on the updated wheel-rail tangential force calculation result.

[0095] The step of performing tangential contact analysis calculations based on the wheel-rail friction coefficient and the updated wheel-rail normal force calculation results to obtain the wheel-rail tangential force calculation results includes:

[0096] The longitudinal and lateral creep rates of the wheel and rail are determined as the initial conditions for iteration. Based on the pre-acquired wheel and rail spin creep rate, the longitudinal creep rate, the lateral creep rate, the wheel and rail friction coefficient, and the wheel and rail normal force, the calculation results are updated and superimposed to obtain the wheel and rail tangential stress under the current working condition.

[0097] The wheel-rail tangential stress is integrated within the pre-obtained wheel-rail contact patch area to obtain the wheel-rail tangential force calculation result.

[0098] The following steps are followed to solve for the local information of wheel-rail tangential contact by combining the Kalker variational method and the Newton-Raphson iterative method:

[0099] E1: Calculate the wheel-rail spin creep rate based on the wheelset lateral displacement and track unevenness.

[0100] E2: Assume a relatively large longitudinal and lateral creep rate of the wheel and rail as the initial condition for iteration.

[0101] E3: Using the wheel-rail friction coefficient and the wheel-rail normal pressure (as the result of updating the wheel-rail normal force calculation) as input conditions, and combining the obtained longitudinal creep rate, lateral creep rate, and wheel-rail spin creep rate, the wheel-rail tangential contact under the above working conditions is calculated based on the Kalker variational method TANG algorithm, obtaining the adhesion zone / sliding zone distribution, wheel-rail tangential stress, local sliding velocity distribution, etc. (e.g.) Figure 5 As shown in the figure, the wheel-rail tangential stress is integrated over the contact patch region to obtain the longitudinal and lateral creep forces (i.e., the calculated wheel-rail tangential forces). For Figure 5 Further explanation: Calculation conditions: Wheel LMA, 60mm rail, wheelset lateral displacement 0 mm, yaw rate 0 rad, normal force N = 73.4 kN, longitudinal creep rate cx = -2.5 × 10⁻⁶ -4 The lateral creep rate cy = -2.5 × 10 -4 The spin creep rate is cz = -0.0603. The area enclosed by the red line represents the sliding zone. Different colors distinguish the resultant tangential stress, and the arrow indicates the shear stress vector.

[0102] The calculated wheel-rail tangential force includes the calculated longitudinal creep force and the calculated lateral creep force of the wheel and rail, and the measured wheel-rail tangential force includes the longitudinal creep force and the lateral creep force of the wheel and rail; correspondingly, updating the wheel-rail tangential force calculated based on the comparison between the calculated wheel-rail tangential force and the measured wheel-rail tangential force includes:

[0103] If it is determined that the comparison result between the longitudinal creep force calculation result and the longitudinal creep force, and the comparison result between the lateral creep force calculation result and the lateral creep force are both less than a preset difference, then the wheel-rail tangential force calculation result at this time is determined as the wheel-rail tangential force update calculation result.

[0104] If at least one comparison result is determined to be greater than or equal to the preset difference, then the step of updating the wheel-rail tangential force calculation result continues.

[0105] E4: Determine whether the differences between the longitudinal and lateral creep forces of the wheel and rail calculated in E3 and the reverse-calculated longitudinal and lateral creep forces of the wheel and rail are both less than the preset difference values. If not, use the Newton-Raphson iteration to update the longitudinal and lateral creep rates of the wheel and rail, and proceed to the next iteration. If yes, terminate the iteration, complete the tangential contact calculation, and obtain the updated wheel-rail tangential force calculation results, i.e., the updated longitudinal and lateral creep rates of the wheel and rail. The local contact information of the wheel and rail can then be reflected through the updated wheel-rail tangential force calculation results.

[0106] The method for obtaining wheel-rail local contact information provided in the embodiments of the present invention will be further described as follows:

[0107] To implement the reverse calculation of local wheel-rail contact information, this invention, focusing on the wheel-rail profile and disregarding the wheelset roll angle, determines the wheelset roll angle based on two-dimensional wheel-rail contact geometry analysis, and obtains the positions and relative motion attitudes of the left and right contact points, i.e., the relationship between the wheelset lateral displacement, the rail irregularity, and the rail gauge. Table 1 shows the relationship between the positions and relative motion attitudes of the left and right contact points. Based on the left and right wheel-rail contact point positions obtained from the force-measuring wheelset test, the relative motion attitudes of the wheel and rail, i.e., the wheelset lateral displacement, the rail irregularity, and the rail gauge, are obtained by referring to Table 1.

[0108] To solve the three-dimensional contact geometry of the wheel and rail, this invention solves the three-dimensional contact geometry based on the wheel and rail profile and the wheelset lateral displacement, rail irregularity and track gauge obtained by reverse calculation, determines the wheel and rail contact plane, and solves the wheel and rail normal clearance when the wheel and rail are initially in contact and have not deformed. The wheel and rail vertical force, wheel and rail lateral force, and wheel and rail longitudinal force in the overall coordinate system obtained by the test are transformed into contact patch coordinates to obtain the wheel and rail normal force and wheel and rail longitudinal / lateral creep force.

[0109] To solve for wheel-rail normal contact, this invention uses the Kalker variational method to calculate the wheel-rail normal contact state. In the calculation, the Newton-Raphson iterative wheel-rail compression is used to make the calculated wheel-rail normal force equal to the inversely derived wheel-rail normal force. The wheel-rail normal contact is calculated using the obtained wheel-rail compression, and the wheel-rail normal pressure distribution in the wheel-rail contact area and contact patch is obtained.

[0110] To solve the wheel-rail tangential contact problem, this invention utilizes the obtained normal stress distribution within the contact patch and the wheel-rail environmental conditions during testing. Based on the Kalker variational method, it calculates the wheel-rail tangential contact state under the test wheel-rail tangential force condition. In the calculation, the Newton-Raphson iteration of the wheel-rail creep rate (iter only for longitudinal and lateral creep rates, while the spin creep rate is obtained theoretically by relative lateral displacement) is used to ensure that the calculated wheel-rail creep force equals the test wheel-rail creep force. The wheel-rail tangential contact is calculated using the determined wheel-rail creep rate, obtaining parameters such as the distribution of the adhesion / sliding zone, the wheel-rail tangential contact stress distribution, and the local sliding velocity distribution within the wheel-rail contact area.

[0111] The method for obtaining wheel-rail local contact information provided in this embodiment of the invention has the following beneficial technical effects:

[0112] 1. This invention proposes a method for back-calculating wheel-rail local contact information based on force-measuring wheelsets. The method for back-calculating wheel-rail motion information based on measured wheel-rail forces and wheel-rail contact positions is more accurate than vehicle dynamics simulation results, and thus significantly improves the prediction accuracy of wheel-rail local contact information based on wheel-rail motion information.

[0113] 2. This invention overcomes the shortcomings of current force-measuring wheelsets, which can only measure the resultant force between wheel and rail but cannot predict the internal contact information of the wheel-rail contact patch, thus improving the measurement range of the force-measuring wheelsets.

[0114] 3. This invention is based on the Kalker variational method and the Newton-Raphson iterative method to back-calculate the wheel-rail normal relative motion and wheel-rail creep rate, and obtains wheel-rail local contact information. The back-calculation efficiency and accuracy are excellent.

[0115] The wheel-rail local contact information acquisition method provided in this embodiment of the invention determines the wheelset lateral displacement, rail irregularity, and rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset based on a correspondence relationship. The correspondence relationship is a relationship between a preset wheel-rail contact point position, a preset wheelset lateral displacement and rail irregularity, and a preset rail gauge. The wheel-rail contact geometry is determined based on the wheel-rail profile, the wheelset lateral displacement and rail irregularity, and the rail gauge. The measured wheel-rail normal force and measured wheel-rail tangential force are obtained based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset. The normal force is calculated based on the wheel-rail contact geometry. Contact analysis calculations are performed to obtain the wheel-rail normal force calculation results. These results are then updated based on a comparison between the calculated wheel-rail normal force and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result. Tangential contact analysis calculations are then performed based on the wheel-rail friction coefficient and the updated wheel-rail normal force calculation results to obtain the wheel-rail tangential force calculation results. These updated wheel-rail tangential force calculation results are then updated based on a comparison between the calculated wheel-rail tangential force and the measured wheel-rail tangential force. The updated wheel-rail tangential force calculation results determine the local wheel-rail contact information, which improves the accuracy of obtaining local wheel-rail contact information and provides a basis for assessing wheel-rail interface degradation.

[0116] In the above optional embodiments, the wheel-rail contact geometry includes the wheel-rail normal clearance and the contact plane; correspondingly, determining the wheel-rail contact geometry based on the wheel-rail profile, wheelset lateral displacement and rail irregularity, and rail gauge includes:

[0117] The positions of the wheel profile and rail profile in three-dimensional space are determined based on the wheel-rail profile, wheelset lateral displacement and rail irregularity, and rail gauge; the above embodiments can be referred to for explanation, and will not be repeated here.

[0118] The wheel-rail normal clearance and the position of the contact origin when the wheel and rail are initially in contact and have not deformed are obtained based on the positions of the wheel profile and rail profile in three-dimensional space; this can be referred to the above embodiments for explanation, and will not be repeated here.

[0119] The contact plane is determined based on the location of the contact origin. This can be referred to the above embodiments for further explanation, and will not be repeated here.

[0120] In the above optional embodiments, obtaining the measured wheel-rail normal force and measured wheel-rail tangential force based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset includes:

[0121] The wheel-rail coordinate system direction is determined based on the wheel-rail contact geometry. Then, coordinate transformations are performed on the vertical, lateral, and longitudinal forces of the wheel-rail pair based on this coordinate system direction to obtain the measured wheel-rail normal force and the measured wheel-rail tangential force. This can be referred to the above embodiments for further explanation and will not be repeated here.

[0122] In the above optional embodiments, the step of performing normal contact analysis calculation based on the wheel-rail contact geometry to obtain the wheel-rail normal force calculation result includes:

[0123] The maximum wheel-rail compression is determined as the initial condition for iteration, and the relative wheel-rail compression is obtained by superimposing the wheel-rail normal gap; this can be referred to the above embodiment for explanation, and will not be repeated here.

[0124] The wheel-rail contact area and wheel-rail normal pressure are obtained by performing normal contact calculation based on the relative compression of the wheel and rail; the above embodiments can be referred to for explanation, and will not be repeated here.

[0125] The wheel-rail normal pressure is integrated within the wheel-rail contact patch area to obtain the calculated wheel-rail normal force. This can be referred to the above embodiment for further explanation and will not be repeated here.

[0126] In the above optional embodiments, the step of performing tangential contact analysis calculation based on the wheel-rail friction coefficient and the updated wheel-rail normal force calculation results to obtain the wheel-rail tangential force calculation results includes:

[0127] The longitudinal and lateral creep rates of the wheel and rail are determined as the initial conditions for iteration. Based on the pre-acquired wheel and rail spin creep rate, the longitudinal creep rate, the lateral creep rate, the wheel and rail friction coefficient, and the wheel and rail normal force, the calculation results are updated and superimposed to obtain the wheel and rail tangential stress under the current working condition. The above embodiments can be referred to for explanation, and will not be repeated here.

[0128] The wheel-rail tangential stress is integrated within the pre-obtained wheel-rail contact patch area to obtain the calculated wheel-rail tangential force. This can be referred to the above embodiment for further explanation and will not be repeated here.

[0129] In the above optional embodiments, the wheel-rail tangential force calculation result includes the longitudinal creep force calculation result and the lateral creep force calculation result of the wheel and rail, and the measured wheel-rail tangential force includes the longitudinal creep force and the lateral creep force of the wheel and rail; correspondingly, updating the wheel-rail tangential force calculation result based on the comparison result between the wheel-rail tangential force calculation result and the measured wheel-rail tangential force includes:

[0130] If it is determined that the comparison result between the longitudinal creep force calculation result and the longitudinal creep force, as well as the comparison result between the lateral creep force calculation result and the lateral creep force, are both less than a preset difference, then the wheel-rail tangential force calculation result at this time is determined as the updated wheel-rail tangential force calculation result; this can be referred to the above embodiment for explanation, and will not be repeated here.

[0131] If at least one comparison result is determined to be greater than or equal to the preset difference, then the step of updating the wheel-rail tangential force calculation result continues. This can be referred to the above embodiment for explanation, and will not be repeated here.

[0132] Figure 6 This is a schematic diagram of the structure of a wheel-rail partial contact information acquisition device provided in an embodiment of the present invention, as shown below. Figure 6 As shown, the wheel-rail partial contact information acquisition device provided in this embodiment of the invention includes a determination unit 601, an acquisition unit 602, a first calculation unit 603, and a second calculation unit 604, wherein:

[0133] The determining unit 601 is used to determine the wheelset lateral displacement, rail irregularity, and rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset according to the corresponding relationship; wherein, the corresponding relationship is the correspondence between the preset wheel-rail contact point position, the preset wheelset lateral displacement, the rail irregularity, and the preset rail gauge; the acquiring unit 602 is used to determine the wheel-rail contact geometry based on the wheel-rail profile, the wheelset lateral displacement and rail irregularity, and the rail gauge, and to acquire the measured wheel-rail normal force and the measured wheel-rail tangential force based on the wheel-rail contact geometry, the wheel-rail vertical force, the wheel-rail lateral force, and the wheel-rail longitudinal force of the force-measuring wheelset; the first calculation unit 603 is used to calculate the wheel-rail contact geometry based on the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset; The normal contact analysis calculation is performed based on the stated wheel-rail contact geometry to obtain the wheel-rail normal force calculation result. The wheel-rail normal force calculation result is then updated based on a comparison between the calculated wheel-rail normal force and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result. The second calculation unit 604 performs tangential contact analysis calculation based on the wheel-rail friction coefficient and the updated wheel-rail normal force calculation result to obtain the wheel-rail tangential force calculation result. The wheel-rail tangential force calculation result is then updated based on a comparison between the calculated wheel-rail tangential force and the measured wheel-rail tangential force, and the wheel-rail local contact information is determined based on the updated wheel-rail tangential force calculation result.

[0134] Specifically, the determining unit 601 in the device is used to determine the wheelset lateral displacement, rail irregularity, and rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset according to the corresponding relationship; wherein, the corresponding relationship is the correspondence between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail irregularity, and the preset rail gauge; the acquiring unit 602 is used to determine the wheel-rail contact geometry based on the wheel-rail profile, the wheelset lateral displacement and rail irregularity, and the rail gauge, and to acquire the measured wheel-rail normal force and measured wheel-rail tangential force based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset; the first calculation unit 60... Unit 3 is used to perform normal contact analysis calculations based on the wheel-rail contact geometry to obtain the wheel-rail normal force calculation results, and to update the wheel-rail normal force calculation results based on the comparison between the wheel-rail normal force calculation results and the measured wheel-rail normal force, thus obtaining updated wheel-rail normal force calculation results; Unit 604 is used to perform tangential contact analysis calculations based on the wheel-rail friction coefficient and the updated wheel-rail normal force calculation results to obtain the wheel-rail tangential force calculation results, and to update the wheel-rail tangential force calculation results based on the comparison between the wheel-rail tangential force calculation results and the measured wheel-rail tangential force, thus determining wheel-rail local contact information based on the updated wheel-rail tangential force calculation results.

[0135] The wheel-rail partial contact information acquisition device provided in this embodiment of the invention determines the wheelset lateral displacement, rail irregularity, and rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset based on a correspondence relationship. The correspondence relationship is a relationship between a preset wheel-rail contact point position, a preset wheelset lateral displacement and rail irregularity, and a preset rail gauge. The device determines the wheel-rail contact geometry based on the wheel-rail profile, the wheelset lateral displacement and rail irregularity, and the rail gauge. Based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset, the device acquires the measured wheel-rail normal force and the measured wheel-rail tangential force. The device then performs normal force calculation based on the wheel-rail contact geometry. Contact analysis calculations are performed to obtain the wheel-rail normal force calculation results. These results are then updated based on a comparison between the calculated wheel-rail normal force and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result. Tangential contact analysis calculations are then performed based on the wheel-rail friction coefficient and the updated wheel-rail normal force calculation results to obtain the wheel-rail tangential force calculation results. These updated wheel-rail tangential force calculation results are then updated based on a comparison between the calculated wheel-rail tangential force and the measured wheel-rail tangential force. The updated wheel-rail tangential force calculation results determine the local wheel-rail contact information, which improves the accuracy of obtaining local wheel-rail contact information and provides a basis for assessing wheel-rail interface degradation.

[0136] The embodiments of the present invention provide a wheel-rail partial contact information acquisition device that can be used to execute the processing flow of the above method embodiments. Its functions will not be repeated here, but can be referred to the detailed description of the above method embodiments.

[0137] Figure 7 This is a schematic diagram of the physical structure of a computer device provided in an embodiment of the present invention, such as... Figure 7 As shown, the computer device includes: a memory 701, a processor 702, and a computer program stored in the memory 701 and executable on the processor 702. When the processor 702 executes the computer program, it implements the following method:

[0138] Based on the correspondence, determine the lateral displacement of the wheelset, the rail irregularity, and the rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset;

[0139] The correspondence is the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail unevenness, and the preset rail gauge.

[0140] The wheel-rail contact geometry is determined based on the wheel-rail profile, wheelset lateral displacement and track irregularity, and rail gauge. The measured wheel-rail normal force and measured wheel-rail tangential force are obtained based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset.

[0141] Based on the stated wheel-rail contact geometry, a normal contact analysis calculation is performed to obtain the wheel-rail normal force calculation result. The wheel-rail normal force calculation result is then updated based on the comparison between the stated wheel-rail normal force calculation result and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result.

[0142] Tangential contact analysis is performed based on the wheel-rail friction coefficient and the updated calculation results of the wheel-rail normal force to obtain the wheel-rail tangential force calculation results. The wheel-rail tangential force calculation results are then updated based on the comparison between the wheel-rail tangential force calculation results and the measured wheel-rail tangential force. Based on the updated wheel-rail tangential force calculation results, the local wheel-rail contact information is determined.

[0143] This embodiment discloses a computer program product, which includes a computer program that, when executed by a processor, implements the following method:

[0144] Based on the correspondence, determine the lateral displacement of the wheelset, the rail irregularity, and the rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset;

[0145] The correspondence is the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail unevenness, and the preset rail gauge.

[0146] The wheel-rail contact geometry is determined based on the wheel-rail profile, wheelset lateral displacement and track irregularity, and rail gauge. The measured wheel-rail normal force and measured wheel-rail tangential force are obtained based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset.

[0147] Based on the stated wheel-rail contact geometry, a normal contact analysis calculation is performed to obtain the wheel-rail normal force calculation result. The wheel-rail normal force calculation result is then updated based on the comparison between the stated wheel-rail normal force calculation result and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result.

[0148] Tangential contact analysis is performed based on the wheel-rail friction coefficient and the updated calculation results of the wheel-rail normal force to obtain the wheel-rail tangential force calculation results. The wheel-rail tangential force calculation results are then updated based on the comparison between the wheel-rail tangential force calculation results and the measured wheel-rail tangential force. Based on the updated wheel-rail tangential force calculation results, the local wheel-rail contact information is determined.

[0149] This embodiment provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the following method:

[0150] Based on the correspondence, determine the lateral displacement of the wheelset, the rail irregularity, and the rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset;

[0151] The correspondence is the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail unevenness, and the preset rail gauge.

[0152] The wheel-rail contact geometry is determined based on the wheel-rail profile, wheelset lateral displacement and track irregularity, and rail gauge. The measured wheel-rail normal force and measured wheel-rail tangential force are obtained based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset.

[0153] Based on the stated wheel-rail contact geometry, a normal contact analysis calculation is performed to obtain the wheel-rail normal force calculation result. The wheel-rail normal force calculation result is then updated based on the comparison between the stated wheel-rail normal force calculation result and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result.

[0154] Tangential contact analysis is performed based on the wheel-rail friction coefficient and the updated calculation results of the wheel-rail normal force to obtain the wheel-rail tangential force calculation results. The wheel-rail tangential force calculation results are then updated based on the comparison between the wheel-rail tangential force calculation results and the measured wheel-rail tangential force. Based on the updated wheel-rail tangential force calculation results, the local wheel-rail contact information is determined.

[0155] Compared with existing technical solutions, the wheel-rail local contact information acquisition method provided in this invention determines the wheelset lateral displacement, rail irregularity, and rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset based on a correspondence relationship. The correspondence relationship is between a preset wheel-rail contact point position, a preset wheelset lateral displacement and rail irregularity, and a preset rail gauge. The wheel-rail contact geometry is determined based on the wheel-rail profile, the wheelset lateral displacement and rail irregularity, and the rail gauge. The measured wheel-rail normal force and measured wheel-rail tangential force are obtained based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset. Normal contact analysis is performed on the contact geometry to obtain the wheel-rail normal force calculation result. The wheel-rail normal force calculation result is updated based on the comparison between the calculated wheel-rail normal force result and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result. Tangential contact analysis is performed based on the wheel-rail friction coefficient and the updated wheel-rail normal force calculation result to obtain the wheel-rail tangential force calculation result. The wheel-rail tangential force calculation result is updated based on the comparison between the calculated wheel-rail tangential force result and the measured wheel-rail tangential force. The local wheel-rail contact information is determined based on the updated wheel-rail tangential force calculation result, which can improve the accuracy of obtaining local wheel-rail contact information and is beneficial for providing a basis for assessing wheel-rail interface degradation.

[0156] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0157] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0158] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0159] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0160] In the description of this specification, the references to terms such as "an embodiment," "a specific embodiment," "some embodiments," "for example," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0161] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for acquiring wheel-rail local contact information, characterized in that, include: Based on the correspondence, determine the lateral displacement of the wheelset, the rail irregularity, and the rail gauge corresponding to the wheel-rail contact point position of the force-measuring wheelset; The correspondence is the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail unevenness, and the preset rail gauge. The wheel-rail contact geometry is determined based on the wheel-rail profile, wheelset lateral displacement and track irregularity, and rail gauge. The measured wheel-rail normal force and measured wheel-rail tangential force are obtained based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset. Based on the stated wheel-rail contact geometry, a normal contact analysis calculation is performed to obtain the wheel-rail normal force calculation result. The wheel-rail normal force calculation result is then updated based on the comparison between the stated wheel-rail normal force calculation result and the measured wheel-rail normal force, resulting in an updated wheel-rail normal force calculation result. Tangential contact analysis is performed based on the wheel-rail friction coefficient and the updated calculation results of the wheel-rail normal force to obtain the wheel-rail tangential force calculation results. The wheel-rail tangential force calculation results are then updated based on the comparison between the wheel-rail tangential force calculation results and the measured wheel-rail tangential force. Based on the updated wheel-rail tangential force calculation results, the local wheel-rail contact information is determined.

2. The method for obtaining wheel-rail partial contact information according to claim 1, characterized in that, The wheel-rail contact geometry includes the wheel-rail normal clearance and the contact plane; correspondingly, determining the wheel-rail contact geometry based on the wheel-rail profile, wheelset lateral displacement and track irregularity, and rail gauge includes: The positions of the wheel profile and rail profile in three-dimensional space are determined based on the wheel-rail profile, wheelset lateral displacement and rail irregularity, and rail gauge. The wheel-rail normal clearance and the position of the contact origin are obtained when the wheel and rail are initially in contact and have not deformed, based on the positions of the wheel profile and rail profile in three-dimensional space. The contact plane is determined based on the location of the contact origin.

3. The method for obtaining wheel-rail partial contact information according to claim 1, characterized in that, The process of obtaining the measured wheel-rail normal force and measured wheel-rail tangential force based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset includes: The wheel-rail coordinate system direction is determined based on the wheel-rail contact geometry. The wheel-rail vertical force, wheel-rail lateral force, and wheel-rail longitudinal force of the force-measuring wheelset are then transformed according to the wheel-rail coordinate system direction to obtain the measured wheel-rail normal force and the measured wheel-rail tangential force.

4. The method for obtaining wheel-rail partial contact information according to claim 2, characterized in that, The step of performing normal contact analysis calculations based on the wheel-rail contact geometry to obtain the wheel-rail normal force calculation results includes: The maximum wheel-rail compression is determined as the initial condition for iteration, and the relative wheel-rail compression is obtained by superimposing the wheel-rail normal clearance. Based on the relative compression of the wheel and rail, normal contact calculation is performed to obtain the wheel-rail contact patch area and the wheel-rail normal pressure. The wheel-rail normal pressure is integrated within the wheel-rail contact patch area to obtain the wheel-rail normal force calculation result.

5. The method for obtaining wheel-rail partial contact information according to claim 4, characterized in that, The step of performing tangential contact analysis calculations based on the wheel-rail friction coefficient and the updated wheel-rail normal force calculation results to obtain the wheel-rail tangential force calculation results includes: The longitudinal and lateral creep rates of the wheel and rail are determined as the initial conditions for iteration. Based on the pre-acquired wheel and rail spin creep rate, the longitudinal creep rate, the lateral creep rate, the wheel and rail friction coefficient, and the wheel and rail normal force, the calculation results are updated and superimposed to obtain the wheel and rail tangential stress under the current working condition. The wheel-rail tangential stress is integrated within the pre-obtained wheel-rail contact patch area to obtain the wheel-rail tangential force calculation result.

6. The method for obtaining wheel-rail partial contact information according to any one of claims 1 to 5, characterized in that, The wheel-rail tangential force calculation results include the longitudinal creep force calculation results and the lateral creep force calculation results of the wheel and rail, and the measured wheel-rail tangential force includes the longitudinal creep force and the lateral creep force of the wheel and rail; Accordingly, updating the wheel-rail tangential force calculation result based on the comparison result between the calculated wheel-rail tangential force and the measured wheel-rail tangential force includes: If it is determined that the comparison result between the longitudinal creep force calculation result and the longitudinal creep force, and the comparison result between the lateral creep force calculation result and the lateral creep force are both less than a preset difference, then the wheel-rail tangential force calculation result at this time is determined as the wheel-rail tangential force update calculation result. If at least one comparison result is determined to be greater than or equal to the preset difference, then the step of updating the wheel-rail tangential force calculation result continues.

7. A device for acquiring partial wheel-rail contact information, characterized in that, include: The determining unit is used to determine the lateral displacement of the wheelset, the track irregularity, and the rail gauge corresponding to the position of the wheel-rail contact point of the force-measuring wheelset, based on the correspondence relationship. The correspondence is the relationship between the preset wheel-rail contact point position, the preset wheelset lateral displacement and rail unevenness, and the preset rail gauge. The acquisition unit is used to determine the wheel-rail contact geometry based on the wheel-rail profile, wheelset lateral displacement and rail irregularity, and rail gauge, and to acquire the measured wheel-rail normal force and measured wheel-rail tangential force based on the wheel-rail contact geometry, the wheel-rail vertical force, wheel-rail lateral force and wheel-rail longitudinal force of the force-measuring wheelset; The first calculation unit is used to perform normal contact analysis calculation based on the wheel-rail contact geometry to obtain the wheel-rail normal force calculation result, and update the wheel-rail normal force calculation result based on the comparison result between the wheel-rail normal force calculation result and the measured wheel-rail normal force to obtain the updated wheel-rail normal force calculation result. The second calculation unit is used to perform tangential contact analysis calculation based on the wheel-rail friction coefficient and the updated calculation result of the wheel-rail normal force to obtain the wheel-rail tangential force calculation result, update the wheel-rail tangential force calculation result based on the comparison result between the wheel-rail tangential force calculation result and the measured wheel-rail tangential force, and determine the wheel-rail local contact information based on the updated wheel-rail tangential force calculation result.

8. A computer device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the method of any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method of any one of claims 1 to 6.

10. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the method of any one of claims 1 to 6.

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