A vehicle wading simulation method considering surge and actual vehicle speed

Abstract

The present invention relates to the field of automobile simulation test technology, specifically to a whole vehicle wading simulation method that takes surge and real vehicle speed into consideration. It includes collecting data of similar models of the test model during the wading process to obtain a first wading speed function curve; building a whole vehicle wading simulation model, including establishing at least two whole vehicle models, and forming a test group with the front and rear whole vehicle models; using the wading speed function curve as the boundary input of the simulation, conducting a wading simulation test, and simulating different working conditions; extracting and calculating the water impact force of simulated vehicle components, and evaluating the vehicle wading risk. This technical solution can make the wading simulation more consistent with the actual wading conditions of the vehicle.

Description

Technical Field

[0001] The invention relates to the technical field of automobile simulation testing, and in particular to a whole-vehicle wading simulation method taking surge and real vehicle speed into consideration. Background Art

[0002] The vehicle's wading performance is a key indicator for measuring the vehicle's water management performance. It not only reflects the vehicle's adaptability in high humidity environments, but also reveals the vehicle's airtightness. In the process of forward development of vehicle performance, the vehicle's wading performance is an important basis for evaluating the performance of the vehicle, and helps ensure that the vehicle can better adapt to the complex and changing environment of nature. When evaluating the vehicle's wading performance, it is necessary not only to pay attention to whether the vehicle, its systems, and its components have the risk of water leakage or water wetting, but also to pay attention to whether the underbody guard and other components have the risk of breaking or falling off during water impact.

[0003] Currently, there are two main development methods for engineers. One is to directly conduct a vehicle wading test. Although this method can find problems, there are risks such as delayed problem discovery, difficulty in solving some problems, and even possible project delays. Another method is to combine simulation with testing. In the development stage, problems are identified and analyzed and optimized through simulation, and then further rectified by combining test verification in the later stage. This method can quickly discover problems and rectify them in time, reduce problem items in the test stage, formulate solutions in advance, and reduce the risk of vehicle development.

[0004] The current simulation method mainly simulates and analyzes the wading motion curve of the vehicle at a constant speed or with reference to the same power system. However, the working conditions obtained by these two analysis methods are not the severe working conditions of the vehicle wading. Water ingress or bottom guard plate breakage usually occurs when the vehicle wades and collides with the positive waves (such as the wading state of the following vehicle or the surge vehicle). When conducting wading tests, problems also usually occur when the vehicle enters the wading pool and collides with the incoming surge.

[0005] Therefore, it is necessary to optimize the vehicle wading simulation method to better simulate the actual vehicle wading conditions. Summary of the invention

[0006] The purpose of the present invention is to propose a whole vehicle wading simulation method taking into account surge and actual vehicle speed. The technical solution can make the wading simulation more consistent with the actual wading situation of the vehicle.

[0007] To achieve the above purpose, the present invention provides a basic solution: a whole vehicle wading simulation method considering surge and real vehicle speed, comprising:

[0008] Collect data of similar models of the test model during the wading process to obtain the wading speed function curve; build a whole vehicle wading simulation model, including establishing at least two whole vehicle models, and the front and rear whole vehicle models constitute a test group; use the wading speed function curve as the boundary input of the simulation, conduct a wading simulation test, and simulate different working conditions by adjusting the parameters of the two whole vehicle models in the test group; extract and calculate the water impact force of the simulated vehicle components, and evaluate the vehicle wading risk.

[0009] Beneficial effects of the basic solution: This technical solution uses two whole vehicle models to form a test group, which can achieve a complete replication of the calculation model and the test scene. At the same time, by using the wading speed function curve as the simulation input, compared with the existing simulation method, it can greatly improve the consistency with the test results; reduce the error caused by differences in boundary conditions. This technical solution can simulate a variety of different working conditions by adjusting the parameters of the two whole vehicle models in the test group, which is more in line with the actual state of the vehicle wading, and can better cover the harsh working conditions during the vehicle wading process, improve the reliability of simulation analysis, save a lot of manpower, financial resources and time, and shorten the project development cycle.

[0010] As an implementable preferred solution, data of similar models of the test model during the wading process is collected to obtain a wading speed function curve, which specifically includes the following contents:

[0011] The water wading test data of the same type are collected several times, and the water wading test data include the water wading test speed; the water wading test data collected several times are subjected to hourly arithmetic averaging and speed correction processing; after data processing, the water wading vehicle speed function curve is obtained.

[0012] As an implementable preferred solution, the processing principle of performing hourly arithmetic averaging and speed correction processing on the wading test data collected several times is shown in the following formula:

[0013]

[0014]

[0015] In the formula, is the time step of the signal collected by the wading test instrument, S is the wading distance, i is the number of tests, n is the number of time step collections during the test, and v in It refers to the speed in the nth time step of the ith experiment, S new is the wading distance calculated after arithmetic mean processing of the test data, λ is the correction coefficient, is the average vehicle speed within a single time step after correction.

[0016] As an implementable preferred solution, a whole vehicle wading simulation model is built, including establishing at least two whole vehicle models, and the front and rear whole vehicle models constitute a test group, which specifically includes the following contents:

[0017] Obtain detailed vehicle data, vehicle parameters and the vehicle's wading speed function curve; all vehicle components corresponding to the vehicle model are involved in the simulation, including the bottom guard plate and front and rear guards.

[0018] As an implementable preferred solution, the wading speed function curve is used as the boundary input of the simulation, which specifically includes the following contents:

[0019] In the early stage of development, the first wading speed function curve is used as the boundary input of the simulation. In the middle and late stages of development, after a test vehicle is available, the second wading speed function curve is obtained by collecting test data of the test vehicle, and the second wading speed function curve is used to replace the first wading speed function curve as the boundary input of the simulation.

[0020] As an implementable preferred solution, a wading simulation test is conducted to simulate different working conditions, specifically including the following contents:

[0021] The SPH simulation method is adopted; the test group parameters are adjusted to simulate different working conditions. The test group parameters include the time interval between the front and rear vehicles entering the water and the speed and acceleration of the front vehicle.

[0022] As an implementable preferred solution, the test group parameters are adjusted to simulate different working conditions, including the following:

[0023] Adjust the time interval between the front and rear vehicles in the test group entering the water to simulate the following vehicle condition or surge condition; adjust the speed of the front vehicle in the test group to regulate the speed and height of the surge movement, and realize the wading state of repeatedly entering the water and colliding with the surge during the vehicle wading pool test.

[0024] As an implementable optimal solution, the water impact force of simulated vehicle components is extracted and calculated to assess the vehicle's wading risk, which specifically includes the following contents:

[0025] Impact The calculation formula is as follows:

[0026]

[0027] Where ρ is the density of water, is the acceleration due to gravity, is the pressure field gradient in the liquid, μ is the viscosity coefficient of the liquid, is the velocity difference in the liquid flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1It is a logic diagram of a whole vehicle wading simulation method considering surge and real vehicle speed;

[0029] Figure 2 This is an example diagram of the vehicle wading speed function curve after processing;

[0030] Figure 3 A schematic diagram of the simulation of the vehicle following condition for the test group;

[0031] Figure 4 Schematic diagram of the simulation of surge conditions for the test group.

[0032] Figure 5 Schematic diagram of the structure of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0033] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present invention will be further described in detail below in conjunction with the accompanying drawings. It will be understood that the specific embodiments described herein are only partial embodiments of the present invention, which are only used to explain the present application, rather than to limit the present application. It should be noted that the technical features or combinations of technical features described in the following embodiments should not be considered isolated, and they can be combined with each other to achieve better technical effects. The same reference numerals appearing in the drawings of the following embodiments represent the same features or components, which can be applied to different embodiments.

[0034] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of the present invention should have the common meanings understood by those skilled in the art in the art to which the present invention belongs.

[0035] In addition, it should be noted that, in the description of the present invention, the terms "first", "second", "third", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0036] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0037] Explanation of reference numerals: electronic device 500 , processor 501 , communication interface 502 , memory 503 , bus 504 .

[0038] When the vehicle is conducting wading simulation and testing, the wading conditions adopted are: a wading speed of 30km / h when the wading depth is 150mm, and a wading speed of 8km / h when the wading depth is 300m.

[0039] Vehicles will try to maintain a constant speed when wading, but the actual situation is often more complicated. When a vehicle enters the water, the water will create resistance on the vehicle, causing the speed to gradually decrease. In order to maintain the driving speed, the vehicle will increase traction accordingly to accelerate forward. In this process, the speed will fluctuate irregularly.

[0040] This irregular fluctuation not only affects the vehicle's speed, but also the water surface of the wading pool. Due to the acceleration and deceleration of the vehicle, the water surface will shake irregularly. This shaking makes the water impact force on various parts of the vehicle irregular and significantly increases the impact force. Therefore, during the wading process, the vehicle needs to face complex impacts from the water surface.

[0041] In addition, when a vehicle is wading, if there is a high-speed surge in front (such as a return surge caused by the vehicle in front), when the vehicle hits these surges, the impact of water on the components will be further increased. In this case, the components are more likely to break and fall off.

[0042] Reference Figure 1 A vehicle wading simulation method considering surge and real vehicle speed includes:

[0043] Step S100, collecting data of similar models of the test model during the wading process to obtain a first wading speed function curve, wherein the similar models refer to vehicles of the same type and power configuration as the test model, such as sedans or SUVs, with the same or equivalent engine power, and similar volume and weight, specifically including:

[0044] Step S101, collect water wading test data for the same type of vehicle several times through V-box, the water wading test data includes water wading test speed, and in this embodiment, it needs to be collected 3-5 times.

[0045] Step S102, performing hourly arithmetic averaging and speed correction processing on the water wading test data collected for several times. The principle of speed correction processing is shown in the following formula:

[0046]

[0047]

[0048] In the formula, is the time step of the signal collected by the wading test instrument, S is the wading distance, i is the number of tests, n is the number of time step collections during the test, and v in It refers to the velocity in the nth time step of the ith experiment (e.g. v 11 refers to the speed in the first time step of the first wading experiment, S newis the wading distance calculated after arithmetic mean processing of the test data, λ is the correction coefficient, is the average vehicle speed within a single time step after correction.

[0049] Step S103, after data processing, the wading vehicle speed function curve is as follows: Figure 2 As shown, it can be used as the boundary condition input for wading simulation.

[0050] Step S200, building a vehicle wading simulation model, specifically includes:

[0051] Step S201, obtaining detailed vehicle data, vehicle parameters and a wading speed function curve of the vehicle, etc.;

[0052] Step S202, establish at least two complete vehicle models, and all corresponding vehicle parts are involved in the simulation, with a focus on easily damaged vehicle parts, including underbody guards and front and rear guards, so that the water ingress of the vehicle (air tightness of the vehicle), water ingress and wetting of systems and parts, and acceptance of underbody guards and front and rear guards can be investigated. The vehicle model includes simulated underbody guards and front and rear guards and other simulated vehicle parts. The front and rear vehicle models constitute a test group. To ensure the consistency of the test and the simulation, the rear vehicle is a test vehicle (vehicle under development), and the front vehicle preferably uses a completed model for simulation testing. To ensure the development progress, a vehicle under development can also be used for simulation testing.

[0053] Step S300, performing a wading simulation test, using the SPH simulation method, with the help of fluid development software, the wading state of the whole vehicle can be completely reproduced according to the laboratory state, specifically including:

[0054] Step S301, using the first wading speed function curve of the same type of vehicle obtained in step S100 as the boundary input of the simulation, and after a test vehicle is available in the middle and late stages of development, obtaining the second wading speed function curve of the test vehicle by collecting test data of the test vehicle, and using the second wading speed function curve to replace the first wading speed function curve as the boundary input of the simulation.

[0055] Step S302, adjusting the test group parameters to simulate different working conditions, specifically includes:

[0056] Step S302-1, adjust the time interval between the front and rear vehicles in the test group entering the water to simulate the following vehicle condition (such as Figure 3 ) or surge conditions (such as Figure 4). The following vehicle condition refers to the situation where a vehicle simulates following the vehicle in front on the road. When the vehicle is wading, the front vehicle generates waves or water flow that are transmitted backwards during the wading process, and interacts with the rear vehicle (test vehicle) to generate impact force and pressure, which interferes with the movement of the vehicle and also affects the stability and force of the vehicle. The surge condition refers to the transient situation where the vehicle encounters a sudden increase in water level fluctuations during the wading process and is subjected to severe surge impacts, such as rapidly rising floods, water wave impacts caused by vehicles passing by, etc., which cause the vehicle to be subjected to additional water pressure or water flow impacts in a short period of time.

[0057] Step S302-2, adjust the speed of the front vehicle in the test group to adjust the speed and height of the surge movement, and achieve the wading state of the vehicle repeatedly entering the water and hitting the surge during the wading test. The higher the speed and acceleration of the front vehicle, the higher the speed and height of the generated wave movement.

[0058] Step S400, extracting and calculating the water impact force of simulated vehicle components to assess the vehicle's wading risk.

[0059] Impact The calculation formula is as follows:

[0060]

[0061] Where ρ is the density of water, is the acceleration due to gravity, is the pressure field gradient in the liquid, μ is the viscosity coefficient of the liquid, is the velocity difference in the liquid flow.

[0062] By comparing the impact force horizontally Evaluate the risk of vehicle wading and the effectiveness of optimization solutions. In addition, the impact force can also be obtained Export as input for further structural simulation analysis.

[0063] In one embodiment, by combining with third-party result analysis software, with the component installation position as a constraint and the impact force of water as the input boundary condition, the calculation result is the stress and deformation of the component, which further evaluates whether the component is damaged.

[0064] The disclosed embodiments also provide a whole vehicle wading simulation system taking surge and actual vehicle speed into consideration, and the method utilizes a whole vehicle wading simulation method taking surge and actual vehicle speed into consideration in any of the above embodiments.

[0065] The embodiments of the present disclosure further provide a storage medium, in which a computer program is stored. When the computer program is executed by a processor, all steps of a whole vehicle wading simulation method considering surge and actual vehicle speed in any of the above embodiments can be implemented.

[0066] Those skilled in the art can understand that the implementation of all or part of the process in a whole vehicle wading simulation method taking into account surge and real vehicle speed can be completed by instructing related hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include a process of various embodiments of a whole vehicle wading simulation method taking into account surge and real vehicle speed. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0067] The embodiment of the present application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of a vehicle wading simulation method considering surge and real vehicle speed in any of the above embodiments are implemented. In the embodiment of the present application, the processor is the control center of the computer system, which can be a processor of a physical machine or a processor of a virtual machine.

[0068] Reference Figure 3 , the electronic device 500 includes: at least one processor 501, at least one communication interface 502, at least one memory 503 and at least one bus 504. The bus 504 is used to realize the connection and communication between these components, the communication interface 502 is used to communicate signaling or data with other node devices, and the memory 503 stores machine-readable instructions executable by the processor 501. When the electronic device 500 is running, the processor 501 communicates with the memory 503 through the bus 504, and when the machine-readable instructions are called by the processor 501, the steps of a whole vehicle wading simulation method considering surge and actual vehicle speed in any of the above embodiments are executed.

[0069] The above contents are only embodiments of the present invention. The common sense such as the known specific structures and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field to which the invention belongs before the application date or the priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for the ordinary technicians in the relevant field to implement this application. It should be pointed out that for the technicians in this field, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to explain the content of the claims.

Claims

1. A vehicle wading simulation method considering surge and real vehicle speed, characterized by: It includes collecting data of similar models of the test model during the wading process to obtain a wading speed function curve; building a whole vehicle wading simulation model, including establishing at least two whole vehicle models, and forming a test group with the front and rear whole vehicle models; using the wading speed function curve as the boundary input of the simulation, conducting a wading simulation test, and simulating different working conditions; Extract and calculate the water impact force on simulated vehicle parts to assess the vehicle's wading risk; Collect data of similar models of the test model during the wading process to obtain the wading speed function curve, which specifically includes the following contents: Carry out several water wading test data collection for the same type of vehicle, the water wading test data including the water wading test speed; perform hourly arithmetic averaging and speed correction processing on the several collected water wading test data; obtain the first water wading vehicle speed function curve after data processing; The processing principle of performing hourly arithmetic averaging and speed correction processing on the wading test data collected several times is shown in the following formula: In the formula, is the time step of the signal collected by the wading test instrument, S is the wading distance, i is the number of tests, n is the number of time step collections during the test, and v in It refers to the speed in the nth time step of the ith experiment, S new is the wading distance calculated after arithmetic mean processing of the test data, λ is the correction coefficient, is the average vehicle speed within a single time step after correction.

2. A vehicle wading simulation method considering surge and real vehicle speed according to claim 1, characterized in that: Build a whole vehicle wading simulation model, including building at least two whole vehicle models, and the front and rear whole vehicle models constitute a test group, specifically including the following contents: Obtain detailed vehicle data, vehicle parameters and the vehicle's wading speed function curve; all vehicle components corresponding to the vehicle model are involved in the simulation, including the bottom guard plate and front and rear guards.

3. The whole vehicle wading simulation method considering surge and real vehicle speed according to claim 1, characterized in that: The wading speed function curve is used as the boundary input of the simulation, which includes the following: In the early stage of development, the first wading speed function curve is used as the boundary input of the simulation. In the middle and late stages of development, when a test vehicle is available, the second wading speed function curve of the test vehicle is obtained by collecting test data of the test vehicle, and the second wading speed function curve is used to replace the first wading speed function curve as the boundary input of the simulation.

4. The whole vehicle wading simulation method considering surge and real vehicle speed according to claim 1, characterized in that: Carry out wading simulation test to simulate different working conditions, including the following contents: The SPH simulation method is adopted; the test group parameters are adjusted to simulate different working conditions. The test group parameters include the time interval between the front and rear vehicles entering the water and the speed and acceleration of the front vehicle.

5. The whole vehicle wading simulation method considering surge and real vehicle speed according to claim 4, characterized in that: Adjust the test group parameters to simulate different working conditions, including the following: Adjust the time interval between the front and rear vehicles in the test group entering the water to simulate the following vehicle condition or surge condition; adjust the speed of the front vehicle in the test group to regulate the speed and height of the surge movement, and realize the wading state of repeatedly entering the water and colliding with the surge during the vehicle wading pool test.

6. The whole vehicle wading simulation method considering surge and real vehicle speed according to claim 1, characterized in that: Extract and calculate the water impact force of simulated vehicle parts to assess the risk of vehicle wading. Includes the following: Impact The calculation formula is as follows: Where ρ is the density of water, is the acceleration due to gravity, is the pressure field gradient in the liquid, μ is the viscosity coefficient of the liquid, is the velocity difference in the liquid flow.

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