Method and system for calculating energy consumption of wheel and rail friction during operation of railway freight car

Abstract

The application belongs to the technical field of energy consumption calculation, and discloses a railway wagon running process wheel and track friction energy consumption calculation method and system, which comprises the following steps: constructing a normal force coupling model between the wheel and the track; obtaining the dynamic parameters in the running process of the railway wagon, and calculating the sliding speed between the wheel and the track according to the dynamic parameters of the railway wagon; performing nonlinear dynamic correction on the static friction coefficient between the wheel and the track based on the sliding speed, and obtaining the corrected friction coefficient; based on the sliding speed, the corrected friction coefficient and the normal force coupling model, the friction power is calculated and integrated in sections according to different working conditions of the railway wagon, and the friction energy consumption between the wheel and the track is obtained. Through multi-source dynamic load integrated modeling, nonlinear friction coefficient dynamic correction, creep component decoupling and working condition adaptive integration, the application realizes high-precision real-time calculation of the friction energy consumption between the wheel and the track.

Description

Technical Field

[0001] This invention relates to the field of energy consumption calculation technology, and in particular to a method and system for calculating the energy consumption of wheel-rail friction during railway freight car operation. Background Technology

[0002] The statements in this section are merely background information related to the present invention and do not necessarily constitute prior art.

[0003] As a crucial component of railway transportation, freight cars bear the responsibility of transporting goods, resulting in significant energy consumption. A substantial proportion of this energy consumption is attributed to friction between the wheels and rails. Accurately calculating this frictional energy consumption can clarify energy consumption patterns and provide reliable data support for energy conservation and emission reduction.

[0004] Existing methods for calculating frictional energy consumption between wheels and tracks do not consider the dynamic load coupling effect and suffer from problems such as simplified friction coefficient processing and missing operating condition characteristics. This leads to significant errors between the calculated energy consumption and the actual energy consumption, failing to provide an accurate basis for the optimized design of trains. Summary of the Invention

[0005] To address the aforementioned issues, this invention proposes a method and system for calculating the energy consumption of friction between wheels and tracks during railway freight car operation. By integrating multi-source dynamic load modeling, dynamically correcting nonlinear friction coefficients, decoupling creep components, and adaptive integration under operating conditions, the method achieves high-precision real-time calculation of the energy consumption of friction between wheels and tracks.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for calculating the energy consumption due to friction between the wheels and the track during the operation of railway freight cars, comprising the following steps:

[0008] A normal force coupling model between the wheel and the track is constructed. The normal force coupling model includes static normal force and multiple types of dynamic normal force, which are combined according to different operating conditions of railway freight cars.

[0009] Obtain the dynamic parameters of the railway freight car during operation, and calculate the sliding speed between the wheels and the track based on the dynamic parameters of the railway freight car;

[0010] The static friction coefficient between the wheel and the track is nonlinearly and dynamically corrected based on the sliding speed to obtain the corrected friction coefficient.

[0011] Based on the sliding speed, the modified friction coefficient, and the normal force coupling model, the friction power is calculated and integrated in segments according to different operating conditions of railway freight cars to obtain the friction energy consumption between the wheel and the track.

[0012] As an alternative implementation method, the static normal force is the normal contact force generated between the wheels and the rail by the weight of the railway freight car itself.

[0013] Dynamic normal forces include the normal contact force generated by vertical vibration loads, the normal contact force caused by centrifugal force when passing through a curve, and the normal contact force generated by the nodding effect during acceleration or braking.

[0014] As an alternative implementation method, the formula for calculating the energy loss due to friction between the wheel and the track is:

[0015] ;

[0016] in, The coefficient of friction corrected between the wheel and the track. The normal contact force generated by the static axle load component between a single wheel and the rail. The normal contact force between a single wheel and the track is generated by the vertical vibration load excited by track irregularities. This refers to the normal contact force between a single wheel and the rail caused by centrifugal force when a railway freight car passes through a curve. The normal contact force between a single wheel and the rail is caused by the pitching effect resulting from the coupler force during acceleration or braking of a railway freight car. This refers to the sliding speed between the wheel and the track.

[0017] As an alternative implementation method, the formula for calculating the sliding speed between the wheel and the track is:

[0018] ;

[0019] ;

[0020] ;

[0021] in, Longitudinal creep rate, Transverse creep rate, The lateral relative sliding speed between the wheel and the track. For wheel speed, Let be the rolling radius of the wheel.

[0022] As an alternative implementation method, the static friction coefficient is nonlinearly dynamically corrected, as shown in the formula:

[0023] ;

[0024] in, The static friction coefficient is As the attenuation factor, This refers to the sliding speed between the wheel and the track.

[0025] As an alternative implementation method, different operating conditions for railway freight cars include acceleration, constant speed, braking, and curve operation.

[0026] Secondly, the present invention provides a system for calculating the energy consumption due to wheel-rail friction during railway freight car operation, comprising:

[0027] The model building module is configured to: build a normal force coupling model between the wheel and the track, wherein the normal force coupling model includes static normal force and multiple types of dynamic normal force, which are combined according to different operating conditions of railway freight cars;

[0028] The sliding speed calculation module is configured to: acquire the dynamic parameters of the railway freight car during operation, and calculate the sliding speed between the wheels and the track based on the dynamic parameters of the railway freight car;

[0029] The friction coefficient correction module is configured to perform nonlinear dynamic correction on the static friction coefficient between the wheel and the track based on the sliding speed to obtain the corrected friction coefficient.

[0030] The friction energy consumption calculation module is configured to: calculate and integrate the friction power in segments according to different operating conditions of railway freight cars based on the sliding speed, the modified friction coefficient and the normal force coupling model, and obtain the friction energy consumption between the wheel and the track.

[0031] Thirdly, the present invention provides an electronic device including a memory and a processor, and computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the method described in the first aspect.

[0032] Fourthly, the present invention provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the method described in the first aspect.

[0033] Fifthly, the present invention provides a computer program product, including a computer program that, when executed by a processor, implements the method described in the first aspect.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0035] This invention proposes a method for calculating the frictional energy consumption between railway freight cars during operation. Addressing the shortcomings of existing wheel-rail frictional energy consumption models, such as neglecting dynamic load coupling effects, simplifying friction coefficients, and lacking operational characteristics, this invention achieves, for the first time, a complete chain modeling of dynamic load, nonlinear friction, creep decoupling, and operational condition integration. Through multi-source dynamic load integrated modeling, dynamic correction of nonlinear friction coefficients, creep component decoupling, and adaptive operational condition integration, high-precision real-time calculation of frictional energy consumption between wheels and rails is achieved. This solves three major pain points of existing technologies: "lack of dynamic coupling," "oversimplification of friction," and "fuzzy operational characteristics." It provides accurate basis for the optimized design of trains and reliable data support for energy conservation and emission reduction.

[0036] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0037] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0038] Figure 1 This is a flowchart illustrating the method for calculating energy consumption due to wheel-track friction during railway freight car operation, as described in this invention. Detailed Implementation

[0039] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0040] It should be noted that the following detailed description is exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0041] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form as well. Furthermore, it should be understood that the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but includes other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0042] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0043] Example 1

[0044] like Figure 1 As shown in the figure, this embodiment provides a method for calculating the energy consumption due to friction between the wheels and the track during the operation of railway freight cars, including the following steps:

[0045] S1. Construct a normal force coupling model between the wheel and the track. The normal force coupling model includes static normal force and multiple types of dynamic normal force, which are combined according to different operating conditions of railway freight cars.

[0046] S2. Obtain the dynamic parameters of the railway freight car during operation, and calculate the sliding speed between the wheels and the track based on the dynamic parameters of the railway freight car;

[0047] S3. Based on the sliding speed, the static friction coefficient between the wheel and the track is nonlinearly and dynamically corrected to obtain the corrected friction coefficient.

[0048] S4. Based on the sliding speed, the modified friction coefficient, and the normal force coupling model, the friction power is calculated in segments and integrated according to different operating conditions of railway freight cars to obtain the friction energy consumption between the wheel and the track.

[0049] The specific solution of the present invention is as follows:

[0050] S1. Construct a normal force coupling model between the wheel and the track.

[0051] The normal force coupling model of this invention integrates the static normal force of the static axle load and the dynamic normal force generated by three types of dynamic additional loads, wherein the three types of dynamic additional loads include:

[0052] Vertical vibration load: calculated based on unsprung mass and track irregularity acceleration.

[0053] Curve centrifugal load: quantified based on the centrifugal effect of vehicle mass, curve radius, center of gravity height, and speed.

[0054] Longitudinal inertial load: The head-nodding effect is modeled by the relationship between traction / braking acceleration and wheelbase.

[0055] The static normal force and the dynamic normal force generated by the three types of dynamic additional loads are calculated as follows:

[0056] (1) Normal contact force generated by static axle load component.

[0057] The formula for calculating the normal contact force generated between the wheels and rails by the weight of a railway freight car is as follows:

[0058] (1);

[0059] In the formula: The total weight of the railway freight car is N; This refers to the number of wheelsets on a railway freight car.

[0060] (2) Normal contact force generated by vertical vibration load.

[0061] Rail irregularities such as rail welds, uneven rail surfaces, and ballast settlement cause the wheels of freight cars to bounce up and down during operation, creating vertical vibration loads and thus generating normal contact forces between the wheels and the rails. The calculation formula is as follows:

[0062] (2);

[0063] In the formula: The unsprung mass of the axle box springs of railway freight cars, including wheels, axles, and axle boxes, is expressed in kg. The vertical acceleration is obtained through orbital spectrum or actual measurement. Good line Poorly connected lines (such as those in mining areas) can reach (g=9.81) ).

[0064] (3) Normal contact force caused by centrifugal force when passing through a curve.

[0065] The formula for calculating the redistribution of wheel-rail vertical forces caused by centrifugal force when a railway freight car passes over a curved track is as follows:

[0066] (3);

[0067] In the formula: M The weight of the truck is in kg; The speed of the truck is expressed in m / s. R Let be the radius of the curve, in meters. h The vehicle's center of gravity height, in meters (m). d The lateral spacing between the left and right wheel-rail contact points is 1.5 m when the standard track gauge is 1435 mm. K superelevation This is the orbital superelevation correction factor, with a value range of [value range missing]. .

[0068] (4) Normal contact force generated by the nodding effect during acceleration or braking (i.e., normal contact force generated by longitudinal inertial load).

[0069] The formula for calculating the normal contact force generated by the nodding effect caused by the coupler force during acceleration or braking of railway freight cars is as follows:

[0070] (4);

[0071] In the formula: For the longitudinal acceleration of railway freight cars, ; The height of the center of gravity of a railway freight car, in meters (m). The wheelbase of the railway freight car bogie is given in meters (m). This is under traction conditions. >0; During braking operation <0.

[0072] S2. Obtain the dynamic parameters of the railway freight car during operation, and calculate the sliding speed between the wheels and the track based on the dynamic parameters of the railway freight car.

[0073] Table 1 shows the main dynamic parameters and other calculation-related parameters obtained during the operation of railway freight cars. The sliding speed between the wheels and the track is calculated based on the obtained parameters.

[0074] Table 1. Main calculation parameters and their acquisition methods;

[0075]

[0076] The method for calculating the sliding speed between the wheel and the track is as follows:

[0077] (5);

[0078] (6);

[0079] (7);

[0080] Longitudinal creep rate; Transverse creep rate; The lateral relative sliding speed between the wheelset and the rail is expressed in m / s. The wheel speed is expressed in rad / s. Let be the rolling radius of the wheel, in meters (m).

[0081] S3. Based on the sliding speed, the static friction coefficient between the wheel and the track is nonlinearly and dynamically corrected to obtain the corrected friction coefficient.

[0082] A velocity-dependent saturation function is used to replace the Coulomb constant model (where the Coulomb constant model is a highly simplified ideal model, treating the static friction coefficient as a constant; the velocity-dependent saturation function is a formula used to correct the shortcomings of the Coulomb constant model, describing the dynamic characteristics of the friction coefficient changing with sliding speed), enabling adaptation to complex environments such as dry / wet rails. Its calculation method is as follows:

[0083] (8);

[0084] in, The static friction coefficient is 0.45 for clean rails and 0.3 for wet rails. This is the attenuation factor, with a typical value of 30 s / m.

[0085] S4. Based on the sliding speed, the modified friction coefficient, and the normal force coupling model, the friction power is calculated in segments and integrated according to different operating conditions of railway freight cars to obtain the friction energy consumption between the wheel and the track.

[0086] The operation of railway freight cars on the track is divided into acceleration, constant speed, braking and curve combination conditions. The combination method of the normal contact force generated by these conditions with static axle load and three types of dynamic additional loads (vertical vibration load, curve centrifugal load and longitudinal inertial load) is shown in Table 2:

[0087] Table 2. Combination methods of normal contact forces under different working conditions;

[0088]

[0089] Based on the normal contact force under different operating conditions of railway freight cars, the frictional power is calculated segment by segment and integrated to obtain the frictional energy consumption between the wheel and the rail. The energy consumption calculation formula is as follows:

[0090] (9);

[0091] In the formula: E The total structural friction energy consumption between a single wheel and the track, in J; and The start and end times, in seconds, are used to calculate the integral of the total frictional energy consumption between a single wheel and the track. This is the coefficient of friction between the wheel and the track, typically ranging from 0.3 to 0.5. The normal contact force, N, generated by the static axle load component between a single wheel and the rail; The normal contact force between a single wheel and the track, in N, is generated by the vertical vibration load induced by track irregularities. The normal contact force between a single wheel and the rail caused by centrifugal force when a railway freight car passes through a curve, in N; The normal contact force between a single wheel and the rail caused by the pitching effect due to the coupler force during acceleration or braking of a railway freight car, in N; denoted as , which is the sliding speed in the contact area between the wheel and the track, in m / s.

[0092] Based on the above formula, the frictional energy consumption between the wheel and the track is calculated. This invention achieves high-precision real-time calculation of the frictional energy consumption between the wheel and the track through multi-source dynamic load integrated modeling, dynamic correction of nonlinear friction coefficient, decoupling of creep component, and adaptive integration under working conditions. It solves the three major pain points of existing technologies: "lack of dynamic coupling", "oversimplification of friction", and "fuzzy working condition characteristics".

[0093] Example 2

[0094] This embodiment provides a system for calculating the energy consumption due to wheel-rail friction during railway freight car operation, including:

[0095] The model building module is configured to: build a normal force coupling model between the wheel and the track, wherein the normal force coupling model includes static normal force and multiple types of dynamic normal force, which are combined according to different operating conditions of railway freight cars;

[0096] The sliding speed calculation module is configured to: acquire the dynamic parameters of the railway freight car during operation, and calculate the sliding speed between the wheels and the track based on the dynamic parameters of the railway freight car;

[0097] The friction coefficient correction module is configured to perform nonlinear dynamic correction on the static friction coefficient between the wheel and the track based on the sliding speed to obtain the corrected friction coefficient.

[0098] The friction energy consumption calculation module is configured to: calculate and integrate the friction power in segments according to different operating conditions of railway freight cars based on the sliding speed, the modified friction coefficient and the normal force coupling model, and obtain the friction energy consumption between the wheel and the track.

[0099] It should be noted that the above modules correspond to the steps in Embodiment 1, and the examples and application scenarios implemented by the above modules and their corresponding steps are the same, but are not limited to the content disclosed in Embodiment 1. It should also be noted that the above modules can be executed in a computer system as part of the system.

[0100] In further embodiments, the following is also provided:

[0101] An electronic device includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the method described in Embodiment 1. For brevity, further details are omitted here.

[0102] It should be understood that in this embodiment, the processor can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor.

[0103] A computer-readable storage medium for storing computer instructions that, when executed by a processor, perform the method of Embodiment 1.

[0104] The method in Example 1 can be directly executed by a hardware processor, or it can be executed by a combination of hardware and software modules within the processor. The software modules can reside in readily available storage media in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, a detailed description is not provided here.

[0105] A computer program product includes a computer program that, when executed by a processor, implements the method in Embodiment 1.

[0106] The present invention also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, which execute in a device on a target real or virtual processor to perform the processes / methods described above. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc., that perform specific tasks or implement specific abstract data types. In various embodiments, the functionality of program modules can be combined or divided among program modules as needed. The machine-executable instructions for the program modules can execute within a local or distributed device. In a distributed device, the program modules can reside in both local and remote storage media.

[0107] The computer program code used to implement the methods of the present invention may be written in one or more programming languages. This computer program code may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the computer or other programmable data processing device, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a computer, partially on a computer, as a stand-alone software package, partially on a computer and partially on a remote computer, or entirely on a remote computer or server.

[0108] In the context of this invention, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, and the like. Examples of signals may include electrical, optical, radio, sound, or other forms of propagation signals, such as carrier waves, infrared signals, etc.

[0109] Those skilled in the art will recognize that the units and algorithm steps described in conjunction with the embodiments herein can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0110] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for calculating energy loss due to friction between railway freight wheels and rails during operation, characterized in that, Includes the following steps: A normal force coupling model between the wheel and the track is constructed. This model includes static normal force and various types of dynamic normal force, combined according to different operating conditions of railway freight cars. The static normal force is the normal contact force generated between the wheel and the track by the weight of the freight car itself. The dynamic normal force includes the normal contact force generated by vertical vibration loads, the normal contact force caused by centrifugal force when crossing curves, and the normal contact force generated by the nose-nodding effect during acceleration or braking. The static normal force... The calculation formula is: ,in The total weight of the railway freight car is N; This refers to the number of wheelsets on a railway freight car. The normal contact force generated by the vertical vibration load The calculation formula is: ,in The unsprung mass of the axle box springs of railway freight cars, including wheels, axles, and axle boxes, is expressed in kg. The vertical acceleration is obtained through orbital spectrum or actual measurement. . The normal contact force caused by the centrifugal force The calculation formula is: ,in M The weight of the truck is in kg; The speed of the truck is expressed in m / s. R Let be the radius of the curve, in meters. h The vehicle's center of gravity height, in meters (m). d The lateral spacing between the left and right wheel-rail contact points is 1.5 m when the standard track gauge is 1435 mm. K superelevation This is the orbital superelevation correction factor, with a value ranging from 0.8 to 1.2; The normal contact force generated by the nodding effect The calculation formula is: ,in For the longitudinal acceleration of railway freight cars, ; The height of the center of gravity of a railway freight car, in meters (m). The wheelbase of the railway freight car bogie is in meters (m). Obtain the dynamic parameters of the railway freight car during operation, and calculate the sliding speed between the wheels and the rails based on these parameters. The formula for calculating the sliding speed between the wheels and the rails is as follows: ； ； ； in, Longitudinal creep rate, Transverse creep rate, The lateral relative sliding speed between the wheel and the track. For wheel speed, The rolling radius of the wheel; The static friction coefficient between the wheel and the track is nonlinearly and dynamically corrected based on the sliding speed to obtain the corrected friction coefficient; the formula for nonlinear dynamic correction of the static friction coefficient is as follows: ； in, The static friction coefficient is As the attenuation factor, The sliding speed between the wheel and the track; Based on the sliding speed, the modified friction coefficient, and the normal force coupling model, the friction power is calculated and integrated in segments according to different operating conditions of railway freight cars to obtain the frictional energy dissipation between the wheels and the track. The different operating conditions of railway freight cars include acceleration, constant speed operation, braking, and curved track operation. The formula for calculating the frictional energy dissipation between the wheels and the track is as follows: ； in, The coefficient of friction corrected between the wheel and the track. The normal contact force generated by the static axle load component between a single wheel and the rail. The normal contact force between a single wheel and the track is generated by the vertical vibration load excited by track irregularities. This refers to the normal contact force between a single wheel and the rail caused by centrifugal force when a railway freight car passes through a curve. The normal contact force between a single wheel and the rail is caused by the pitching effect resulting from the coupler force during acceleration or braking of a railway freight car. This refers to the sliding speed between the wheel and the track.

2. The system for calculating energy consumption due to wheel-rail friction during railway freight car operation as described in claim 1, characterized in that, include: The model building module is configured to: build a normal force coupling model between the wheel and the track, wherein the normal force coupling model includes static normal force and multiple types of dynamic normal force, which are combined according to different operating conditions of railway freight cars; The sliding speed calculation module is configured to: acquire the dynamic parameters of the railway freight car during operation, and calculate the sliding speed between the wheels and the track based on the dynamic parameters of the railway freight car; The friction coefficient correction module is configured to perform nonlinear dynamic correction on the static friction coefficient between the wheel and the track based on the sliding speed to obtain the corrected friction coefficient. The friction energy consumption calculation module is configured to: calculate and integrate the friction power in segments according to different operating conditions of railway freight cars based on the sliding speed, the modified friction coefficient and the normal force coupling model, and obtain the friction energy consumption between the wheel and the track.

3. An electronic device, characterized in that, It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the method of claim 1.

4. A computer-readable storage medium, characterized in that, Used to store computer instructions, which, when executed by a processor, perform the method described in claim 1.

5. A computer program product, characterized in that, It includes a computer program that, when executed by a processor, implements the method of claim 1.

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