Cab noise prediction method and system

Abstract

The invention provides a cab noise prediction method and system, and relates to the technical field of vehicle strength analysis, and the method comprises the steps: obtaining a vibration sound transfer function from each cab suspension point to a driver position through different methods when there is a cab real object or a cab model, obtaining suspension point loads under different working conditions, and obtaining a cab noise prediction result; sound transfer functions from cab sound sources to the position of a driver are obtained through different methods, sound power level testing is carried out on each cab sound source, and sound source loads of the cab sound sources are obtained; combining the vibration-sound transfer function and the suspension point load to generate structural sound; generating air sound in combination with the sound transfer function and a cab sound source load; the cab noise is synthesized according to the structural sound and the air sound. According to the invention, the cab noise can be obtained more quickly and accurately.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle strength analysis, and in particular to a method and system for predicting cab noise. Background Art

[0002] The method for predicting cab noise is to establish a cab acoustic model, combine vibration source analysis, acoustic transfer path analysis (TPA), multi-physics field coupling simulation, and experimental data correction to simulate and predict the noise level in the vehicle. It can identify the noise source and transmission path, help optimize the acoustic environment in the design stage, and thus improve driving comfort and reduce the noise impact on drivers and passengers.

[0003] Through effective noise prediction, potential noise problems can be discovered and solved in the early stages of design, thereby improving the overall quality of the vehicle and ensuring the health and pleasure of the driver and passengers. Cabin noise prediction can improve driving comfort and safety, meet noise regulations, enhance the market competitiveness of vehicles, shorten the R&D cycle, reduce development costs, and optimize multidisciplinary design collaboration.

[0004] However, existing noise prediction methods cannot accurately identify the specific impact of the noise sources of each component on the overall noise of the cab, lack effective noise transfer path analysis, and are difficult to accurately predict and control cab noise. In cab noise testing, it is usually necessary to install a large number of sensors to obtain structure-borne sound and airborne sound, and collect load spectrum data during actual driving or work sites, which makes the load spectrum collection test cycle long and costly, resulting in low efficiency and accuracy of noise prediction. Summary of the invention

[0005] In order to solve the technical problems that the existing noise prediction methods in the prior art cannot accurately identify the specific impact of the noise sources of various components on the overall noise of the cab, lack effective noise transfer path analysis, and are difficult to accurately predict and control the cab noise, in the cab noise test, it is usually necessary to install a large number of sensors to obtain structural sound and air sound, and collect load spectrum data on actual driving or working sites, which makes the load spectrum collection test cycle long and costly, resulting in low efficiency and accuracy of noise prediction, the present invention provides a method and system for predicting cab noise.

[0006] The technical solution provided by the embodiment of the present invention is as follows:

[0007] First aspect

[0008] An embodiment of the present invention provides a method for predicting cab noise, comprising:

[0009] S1: Obtain the vibration-acoustic transfer function from each cab suspension point to the driver's position;

[0010] S2: Obtain the suspension point load under different working conditions;

[0011] S3: Obtaining the sound-to-sound transfer function from the cab sound source to the driver's position;

[0012] S4: performing a sound power level test on a cab sound source to obtain a sound source load of the cab sound source, wherein the cab sound source includes an engine, a cooling system, an exhaust system, an air intake system, a hydraulic component, and a transmission component;

[0013] S5: generating structure-borne sound by combining the vibration-acoustic transfer function and the suspension point load;

[0014] S6: generating airborne sound by combining the acoustic-to-acoustic transfer function and the sound source load;

[0015] S7: Synthesize the cab noise according to the structure-borne sound and the airborne sound.

[0016] Second aspect

[0017] An embodiment of the present invention provides a system for predicting cab noise, comprising:

[0018] processor;

[0019] A memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the method for predicting cabin noise according to the first aspect is implemented.

[0020] The third aspect

[0021] An embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, the method for predicting cabin noise according to the first aspect is implemented.

[0022] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0023] In the present invention, by obtaining the vibration-acoustic transfer function and the sound-acoustic transfer function, the noise transfer path can be effectively analyzed, the noise transfer characteristics of each noise source can be accurately predicted, the contribution of different cab sound sources can be identified, the control ability of the cab noise is improved, and the specific influence of each component on the cab noise can be clearly displayed. By establishing a cab model, a vehicle dynamics model and a vehicle statistical energy model, the cab noise level under different working conditions can be simulated in the design stage, the noise level can be estimated, the improvement demand for physical prototypes can be reduced, and development costs and time can be saved. The cab noise prediction is achieved through model simulation technology, which does not rely on the experimental testing of physical prototypes, avoids the testing and rectification work after the prototype is offline, saves product development costs, shortens the product development cycle, reduces the testing cost, and significantly improves the development efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A schematic diagram of a flow chart of a method for predicting cab noise provided by an embodiment of the present invention;

[0026] Figure 2 A schematic diagram of load testing of various suspension points of a cab provided by an embodiment of the present invention;

[0027] Figure 3 A schematic diagram of load simulation at each suspension point of the cab provided by an embodiment of the present invention;

[0028] Figure 4 A schematic diagram of the arrangement of measuring points in the acoustic-to-acoustic transfer function test cab provided by an embodiment of the present invention;

[0029] Figure 5 A schematic diagram of a test of a physical transfer function of a cab provided by an embodiment of the present invention;

[0030] Figure 6 A schematic diagram of structural acoustics provided by an embodiment of the present invention;

[0031] Figure 7 A schematic diagram of the structure of a system for predicting cab noise provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0032] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0033] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the present invention, the meaning expressed by "and / or" can be both, or it can be either of the two.

[0034] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0035] Reference Manual Attached Figure 1 , shows a flow chart of a method for predicting cab noise provided by an embodiment of the present invention.

[0036] An embodiment of the present invention provides a method for predicting cab noise, the method comprising:

[0037] S1: Obtain the vibration-acoustic transfer function from each cab suspension point to the driver's position.

[0038] Among them, finite element analysis is a numerical calculation method that divides a complex physical structure (such as a cab) into many small, simple parts (called "finite elements"), solves each small part, and then combines the results of these small parts to obtain the overall behavior and characteristics. This method is widely used in engineering and physics to analyze stress, deformation, heat conduction, etc. The vibration-acoustic transfer function is a function that describes how vibration propagates from one point to another. In the cab noise analysis, it represents the vibration transfer characteristics from the cab suspension point (such as the point connected to the frame) to the driver's position, which helps to understand the propagation path and intensity of the noise. The cab suspension point refers to the connection position between the cab and the frame. These connection points have a direct impact on the vibration and noise characteristics of the cab.

[0039] In a possible implementation manner, when there is a physical cab, S1 is specifically:

[0040] The vibration-acoustic transfer function from each cab suspension point to the driver's position is obtained through the hammer method, vibration exciter method and volume sound source test method.

[0041] Among them, the hammer method refers to using an impact hammer to apply instantaneous force (such as knocking) to the structure, measuring the vibration response of the structure, and calculating the vibration-acoustic transfer function. The exciter method refers to using an exciter (such as an electric vibration table) to apply continuous vibration excitation to the structure, and obtaining the vibration-acoustic transfer function by measuring the response. The volume sound source test method refers to placing a volume sound source at a specific position, exciting the sound field to measure the response of the structure to sound transfer, and is used to evaluate the sound transfer characteristics of the structure under sound source excitation.

[0042] It should be noted that obtaining the vibration-acoustic transfer function through various means such as the hammer method, the shaker method and the volume sound source test method can accurately evaluate the dynamic and acoustic characteristics of the structure, provide reliable data support for noise and vibration control design, and effectively optimize the comfort of the cab.

[0043] In a possible implementation manner, when there is only a cab model, S1 specifically includes:

[0044] S101: A finite element model of the cab is established by using finite element software, the cab model is simplified and finite element meshed, and material properties and thickness properties are assigned to each panel of the cab.

[0045] Among them, finite element software is a computational tool used for finite element analysis, which can simulate and analyze the mechanical behavior, heat conduction, electromagnetic field and other characteristics of complex structures. Common finite element software includes ANSYS, Abaqus and COMSOL. The cab finite element model is the process of digital modeling of the cab, which involves converting the geometric shape and structural details of the cab into a computer model for subsequent finite element analysis. Finite element meshing is the process of dividing the cab model into many small units (meshes). These small units are used to solve the physical properties of the model. The accuracy of meshing directly affects the accuracy of the analysis results. Material properties and thickness properties are parameters that describe the material properties of the component, including the density, elastic modulus, Poisson's ratio, etc. of the material, as well as the thickness information of the component. These parameters are used to calculate the response of the structure during the analysis process.

[0046] It should be noted that by establishing the finite element model of the cab through finite element software, the geometric shape of the cab can be simplified and meshed, and material and thickness properties can be assigned to each panel.

[0047] S102: With the goal of establishing a cab TB model, various panels are connected in combination with the cab welding point model and corresponding connection units.

[0048] Among them, the cab TB model is a simplified structural model, which is usually used to analyze torsion and bending behavior. In the finite element analysis of the cab, the TB model can represent the overall stiffness and strength characteristics of the cab, helping to analyze its response under dynamic loads. The weld point model refers to the modeling of the weld points at the connection of various components (such as panels) of the cab in the finite element analysis to reflect their connection strength and stiffness. These weld points are usually an important factor affecting the strength of the structure. The connection unit is a unit used in the finite element model to simulate the connection relationship between different components, which can reflect the characteristics of the connection, such as stiffness, damping, etc.

[0049] It should be noted that by combining the welding point model and the corresponding connection units to connect each panel and establish the TB model of the cab, the overall stiffness and strength characteristics of the cab can be more accurately reflected, the reliability and accuracy of the model can be improved, and the response analysis under dynamic loads can be more realistic.

[0050] S103: Establishing a cab acoustic cavity model.

[0051] Among them, the acoustic cavity model refers to a geometric model established in finite element analysis or acoustic simulation to simulate the propagation of sound waves in a specific space (such as inside the cab). This model takes into account the reflection, diffraction and absorption characteristics of sound waves, and can effectively analyze the distribution of the sound field and the sound pressure level.

[0052] S104: coupling the cab TB model and the cab acoustic cavity model to obtain a coupled model.

[0053] Among them, the coupling model combines two or more different types of models (such as structural models and acoustic models) together in the analysis in order to consider the interaction and influence between them. The TB model of the cab (reflecting the structural characteristics) is coupled with the acoustic cavity model (simulating the sound field characteristics) to provide a comprehensive analysis tool.

[0054] S105: In the coupling model, sweep frequency excitation is applied in multiple directions along each cab suspension point to simulate the vibration transmission path from each cab suspension point to the driver's position under actual working conditions.

[0055] Among them, swept frequency excitation is a test method that gradually changes the frequency of the excitation signal to cover a certain frequency range, thereby analyzing the dynamic response of the structure at different frequencies.

[0056] It should be noted that applying swept frequency excitation in the coupling model can effectively simulate the vibration transmission path from each suspension point to the driver's position under actual working conditions, comprehensively evaluate the dynamic characteristics of the cab at different frequencies, and reveal the vibration transmission efficiency and potential resonance frequency of the suspension system.

[0057] S106: Determine the vibration-acoustic transfer function from each cab suspension point to the driver's position using a solver.

[0058] Among them, a solver is an algorithm or tool in numerical computing software that is used to solve equations in mathematical models.

[0059] Specifically, using the solver to determine the vibration-acoustic transfer function from each cab suspension point to the driver's position can provide accurate dynamic response analysis, capture the vibration characteristics of the suspension point at different frequencies, and reveal the relationship between vibration and sound pressure.

[0060] It should be noted that by performing finite element analysis on the physical structure of the cab, the vibration-acoustic transfer function from each suspension point to the driver's position can be accurately determined, and the noise propagation characteristics can be deeply understood, which can help designers optimize the structural layout, effectively control the noise and vibration in the cab, improve ride comfort, and reduce the cost and time of subsequent improvements.

[0061] Reference Manual Attached Figure 2 , showing a schematic diagram of load testing of various suspension points of a cab provided in an embodiment of the present invention.

[0062] like Figure 2, is a schematic diagram of the load test of each suspension point of the cab, including the cab, force sensor, passive bracket and active bracket. It can clearly show the stress conditions and test methods of the cab suspension points, which helps to understand the transmission of vibration of the suspension system under different working conditions and its impact on cab noise.

[0063] Reference Manual Attached Figure 3 , shows a schematic diagram of load simulation at each suspension point of the cab provided by an embodiment of the present invention.

[0064] like Figure 3 It is a simulation diagram of the suspension point load of a vehicle cab, including the cab, suspension point load and working condition load. It shows the connection structure between the cab and the frame, as well as the distribution of the suspension point load under the simulated working state (with working condition load).

[0065] S2: Obtain the suspension point load under different working conditions.

[0066] Among them, the vehicle dynamics model refers to a mathematical model established by analyzing and simulating the motion state and dynamic characteristics of the vehicle. This model takes into account the interaction between the various key components of the vehicle (such as wheels, suspension system, frame, etc.) and their motion and mechanical performance under different working conditions. The suspension point load refers to the load borne on the point (suspension point) connecting the body and frame in the vehicle suspension system. The suspension point load is caused by the interaction force between the various components during the vehicle's driving process.

[0067] In a possible implementation manner, when there is a physical cab, S2 specifically includes:

[0068] S201: Setting the range of the analysis frequency width when collecting the suspension point load:

[0069] f min <f b <f max

[0070] Among them, f min represents the lower limit of the analysis frequency, f b Indicates the analysis frequency width, f max Indicates the upper limit of the analysis frequency;

[0071] S202: collecting the loads of the active side of the suspension point and the passive side of the suspension point respectively according to predefined working conditions within the range of the analysis frequency width, and obtaining the loads of the suspension point under different working conditions;

[0072] In a possible implementation manner, when there is only a cab model, S2 specifically includes:

[0073] S201: Use dynamics software to establish a vehicle dynamics model based on the topological relationship, hard point location, mass properties, kinematic pairs, elastic element characteristics, and damping element characteristics of key vehicle components.

[0074] Among them, topological relationships refer to the geometric and structural relationships between key components of a vehicle, indicating how the components interact and connect through connections and interfaces. Hard point locations refer to the points where certain rigid components in a vehicle (such as frames, bodies, etc.) are fixed or connected. These points are usually used to define the structure and motion constraints of the vehicle. Mass attributes refer to the mass characteristics of each component of a vehicle, including the description of mass distribution and concentrated mass, which has an important impact on the dynamic behavior of the vehicle. Kinematic pairs refer to the mode of connection and constraint between two components, such as hinges and sliding, which affect the relative motion between components. Elastic element characteristics refer to the characteristics of components such as a vehicle suspension system that deform after being subjected to force and can return to their original state, which are usually described by stiffness and elastic coefficients. Damping element characteristics refer to the characteristics of various components of a vehicle (such as suspension systems, shock absorbers, etc.) that consume energy during movement through mechanisms such as friction or fluid resistance, which are usually described by damping coefficients.

[0075] It should be noted that by using dynamics software to establish a vehicle dynamics model, the interactions and motion laws of various vehicle components can be fully considered, accurately reflecting the dynamic response of the vehicle under different working conditions.

[0076] S202: Obtaining vehicle elastic component parameters according to the vehicle dynamics model, and performing flexibility processing on the cab.

[0077] Among them, the vehicle elastic component parameters refer to the characteristic parameters of the elastic components in the vehicle (such as suspension system, body structure, etc.), usually including the stiffness, damping, elastic modulus, etc. of the components. These parameters affect the dynamic response of the vehicle. Flexible processing means that in the modeling process, the rigid components of the vehicle (such as frame, body, etc.) are regarded as components with a certain degree of flexibility, and their deformation and dynamic behavior under force are simulated, so as to more accurately reflect their actual movement and response.

[0078] It should be noted that by obtaining the parameters of the elastic components in the vehicle dynamics model and making the cab flexible, the dynamic response of the vehicle can be simulated more realistically.

[0079] Among them, the rigid-flexible coupling dynamics model of the whole vehicle refers to combining the motion behaviors of the rigid and elastic parts of the vehicle, considering the interaction, elastic deformation and rigid body motion of the various components of the vehicle, so as to obtain a more realistic vehicle dynamic response.

[0080] S204: Obtain the suspension point loads under different working conditions through the rigid-flexible coupling dynamics model of the whole vehicle.

[0081] It should be noted that by establishing a vehicle dynamics model, the dynamic response of each vehicle component under different working conditions can be accurately simulated, and the suspension point load can be accurately predicted, thereby optimizing the design and performance of the suspension system, improving the noise prediction accuracy of the cab, and effectively improving the comfort and noise control performance of the vehicle in actual use.

[0082] Reference Manual Attached Figure 4 , showing a schematic diagram of the arrangement of measuring points in the acoustic-acoustic transfer function test cab provided by an embodiment of the present invention;

[0083] like Figure 4 , showing the measurement point layout of the acoustic-to-acoustic transfer function test, which is used to record acoustic data at different locations, analyze the transfer characteristics of noise from the sound source to the driver's ear, and provide a basis for noise control and optimization design of the cab.

[0084] S3: Obtain the acoustic transfer function from the cab sound source to the driver's position.

[0085] Among them, the vehicle statistical energy model is to establish a mathematical model that describes the energy transfer between the various components of the vehicle and the sound field through statistical energy analysis (SEA). The cab sound source refers to the various system components that affect the cab noise. The sound-to-sound transfer function describes the change law and characteristics of sound energy in the process of sound waves being transmitted from the sound source to the receiving point (such as the driver's position). The engine is the core power source of the car, responsible for converting the chemical energy of the fuel into mechanical energy and driving the car through the combustion process. The main function of the cooling system is to regulate the temperature of the engine to prevent the engine from overheating. The exhaust system is mainly responsible for discharging the exhaust gas after the engine combustion out of the car, usually including exhaust manifold, catalytic converter, muffler and other components. The intake system is responsible for introducing air into the engine for combustion. Hydraulic components are used to control various mechanical movements, usually used in braking systems, steering systems and suspension systems. The transmission components are key components responsible for transmitting the power generated by the engine to the wheels, usually including clutches, transmissions, drive shafts and differentials.

[0086] In a possible implementation manner, when there is a physical cab, S3 specifically includes:

[0087] S301: arranging the cab sound source in the cab, and measuring the volume acceleration of the cab sound source;

[0088] S302: placing a microphone near the cab sound source, and measuring the sound pressure value of the cab sound source by using the microphone;

[0089] S303: Obtain an acoustic-acoustic transfer function according to the volume acceleration and the sound pressure value:

[0090]

[0091]

[0092] L Wf =P Wf -R wf

[0093] in, represents the acoustic transfer function, R Wf P represents the energy-based sound insulation of the vehicle cab to the cab sound source W in the 1 / 3 octave band of the center frequency f, wf It represents the sound pressure value in the 1 / 3 octave band of the center frequency f measured by the microphone at the sound source W in the cab, Q f R represents the volume acceleration of a volume sound source in a frequency band 1 / 3 octave of the center frequency f. wf It represents the average sound insulation from the cab sound source W to the cab in the 1 / 3 octave band with the center frequency f, R if It represents the sound insulation from the i-th surface of the cab sound source W to the cab in the 1 / 3 octave band of the center frequency f, L Wf It represents the contribution of the cab sound source W to the A-weighted sound pressure level in the cab in the 1 / 3 octave band with the center frequency f.

[0094] It should be noted that by conducting sound power level tests on various cab sound sources, the noise output data of each component under different working conditions can be obtained, providing accurate sound source input parameters for cab noise prediction, helping to identify and optimize the main noise sources and improve the acoustic comfort of the cab.

[0095] In a possible implementation, S3 specifically includes:

[0096] S301: Establish a vehicle statistical energy model using statistical energy analysis software.

[0097] Among them, statistical energy analysis software is an engineering method used for acoustic and vibration analysis of complex structures or systems. It is suitable for dealing with high-frequency vibration and acoustic problems, such as VA One, AutoSEA2 and SEAM (Statistical Energy Analysis Model).

[0098] S302: Divide the vehicle into a plurality of coupled subsystems through a whole-vehicle statistical energy model, and establish a subsystem model.

[0099] The coupled subsystem refers to the decomposition of a complex vehicle structure into multiple interconnected parts or modules (subsystems) in statistical energy analysis, and these subsystems interact with each other through energy exchange.

[0100] Specifically, dividing the vehicle into coupled subsystems can simplify the acoustic and vibration analysis of complex structures, improve computational efficiency, and more accurately analyze the impact of different components on the acoustic and vibration performance of the entire vehicle.

[0101] S303: Generate internal and external field acoustic cavities using the subsystem model, and define internal loss factor, coupling loss factor and modal density parameters of each subsystem.

[0102] Among them, the inner and outer field sound cavities refer to the two main areas in the vehicle used for acoustic analysis. The inner field sound cavity represents the interior space of the vehicle (such as the cockpit), and the outer field sound cavity represents the external environment of the vehicle. The internal loss factor represents the energy loss capacity within the subsystem, and is a parameter that measures how the energy is gradually reduced within the subsystem. The coupling loss factor is used to describe the energy transfer efficiency between two coupled subsystems. The modal density parameter represents the number of modes of the subsystem within a specific frequency range, and is used to analyze the vibration and acoustic characteristics within this frequency band.

[0103] It should be noted that by defining these parameters, the energy loss and coupling relationship of each subsystem can be accurately described, which helps improve the prediction accuracy of the acoustic performance of the entire vehicle and optimize the sound insulation design.

[0104] S304: Loading sound power excitation and volume acceleration excitation near the sound source of the cab.

[0105] Among them, sound power excitation refers to applying a certain sound power at the noise source position to simulate the noise level generated by the sound source, and volume acceleration excitation is to excite the sound field through the acceleration change of the sound source volume, which is used to simulate the vibration noise generated by the structure or components.

[0106] S305: Obtain the sound-to-sound transfer function from the cab sound source to the driver's position according to the sound power level and volume acceleration excitation:

[0107]

[0108] Where Q is the volume acceleration and L is the sound power level.

[0109] It should be noted that by establishing a vehicle dynamics model and obtaining the suspension point loads under different working conditions, we can accurately simulate the dynamic behavior of the vehicle under various operating conditions, understand the force transfer path and load distribution of the suspension points under different working conditions, and thus optimize the design of the suspension system, effectively reduce the vibration transmitted to the cab, improve driving comfort, extend the service life of the suspension components, and improve the reliability and durability of the entire vehicle.

[0110] Reference Manual Attached Figure 5 , showing a schematic diagram of a cab physical transfer function test provided by an embodiment of the present invention;

[0111] like Figure 5 , is a schematic diagram of the physical transfer function test of the cab, including the cab, suspension points, cast iron platform, force measurement points and microphone measurement points, showing the layout of the cab transfer function test. By setting microphone measurement points in the cab, force measurement points at the suspension connection and acceleration measurement points on the cast iron platform, the sound pressure, force and acceleration data under different excitation conditions are measured. This test layout can simulate the vibration and noise transfer of the cab in the actual working environment, and provide data support for optimizing the noise and vibration control design of the cab.

[0112] S4: Performing a sound power level test on the cab sound source to obtain the sound source load of the cab sound source.

[0113] Among them, the sound power level refers to the total sound energy radiated by the sound source to the surrounding area per unit time, expressed in sound power level (dB), which is a key indicator for evaluating the intensity of the sound source. The sound source load refers to the noise load generated by each sound source (such as engine, cooling system, etc.) under specific conditions.

[0114] In a possible implementation, the sound source load includes an engine sound source load, a cooling system sound source load, an exhaust sound source load, an intake sound source load, a hydraulic component sound source load, and a transmission component sound source load.

[0115] Among them, the engine sound source load is the noise emitted when the engine is running, the cooling system sound source load is the noise generated by components such as the cooling system fan or pump, the exhaust sound source load is the noise generated during the operation of the exhaust system, the intake sound source load is the noise generated when air enters the engine intake system, the hydraulic component sound source load is the noise generated when the hydraulic system (such as the hydraulic pump) is working, and the transmission component sound source load is the noise generated when the transmission system (such as the gearbox and drive shaft) is running.

[0116] In a possible implementation, S4 specifically includes:

[0117] S401: Determine engine speed data, engine torque data, cooling system speed data, cooling system torque data, exhaust system speed data, exhaust system torque data, intake system speed data, intake system torque data, hydraulic component speed data, hydraulic component torque data, transmission component speed data and transmission component torque data based on speed data and torque data.

[0118] Among them, the speed data refers to the operating speed of each component (such as the engine, cooling system, exhaust system, etc.), which is used to measure the operating frequency and load status of the components. The torque data refers to the torque generated by each component during operation, indicating the output power and load size.

[0119] S402: Perform a sound power level test using an engine bench test according to the engine speed data and the engine torque data to obtain the engine sound source load.

[0120] Among them, engine speed data refers to the operating speed information of the engine under different working conditions, usually expressed in revolutions per minute (RPM), which is used to describe the working state of the engine. Engine torque data refers to the torque output by the engine, which is used to measure the load of the engine under different working conditions. Bench test is a method of testing a single system (such as cooling system, exhaust system, etc.) in a laboratory. By fixing the system and simulating various working conditions, its operating parameters and noise characteristics can be accurately measured.

[0121] S403: Perform a sound power level test using a cooling system bench test according to the cooling system speed data and the cooling system torque data to obtain a cooling system sound source load.

[0122] S404: Perform a sound power level test using an exhaust bench test according to the exhaust system speed data and the exhaust system torque data to obtain the exhaust sound source load.

[0123] S405: Perform a sound power level test using an intake bench test according to the intake system speed data and the intake system torque data to obtain an intake sound source load.

[0124] S406: According to the rotation speed data and the torque data of the hydraulic component, a sound power level test is performed through a bench test of the hydraulic component to obtain a sound source load of the hydraulic component.

[0125] S407: According to the transmission component speed data and the transmission component torque data, a sound power level test is performed through a transmission component bench test to obtain a transmission component sound source load.

[0126] Reference Manual Attached Figure 6 , showing a schematic diagram of structural acoustics provided by an embodiment of the present invention.

[0127] like Figure 6 , showing the transmission process of cab structural noise, the vibration energy is transferred to the interior of the cab from multiple suspension points on the power side and static side of the cab suspension system (such as left front, left rear, right front, right rear, etc.) through the noise transfer function (NTF), and the vibration of each suspension point is accumulated to the target point through NTF and synthesized into the final internal noise level of the cab. It intuitively shows how vibration affects the noise of the cab and provides a basis for optimizing the suspension system and reducing cab noise.

[0128] S5: Generate structure-borne sound by combining the vibro-acoustic transfer function and the suspension point loads.

[0129] Among them, structure-borne sound refers to the sound that is transmitted through solid structures (such as metal, plastic, etc.) and eventually radiated into the air in the form of noise. Structural sound is usually caused by vibration sources, such as the impact caused by the engine, transmission system or uneven roads. These vibrations are transmitted through the vehicle's suspension system, body, frame and other structures, and eventually radiated into the cab or passenger compartment, forming audible noise.

[0130] In a possible implementation, the structure-borne sound is specifically:

[0131]

[0132] Among them, p a Indicates structure-borne sound, F pi represents the suspension point load of the ith suspension point, NTF i represents the vibration-acoustic transfer function of the i-th suspension point, i=1, 2, K, n, and n represents the total number of suspension points.

[0133] It should be noted that combining the vibration-acoustic transfer function and the suspension point load to generate structure-borne sound can more accurately simulate the contribution of vibration to the interior noise of the cab, identify the main noise sources and optimize the structural design, thereby effectively reducing the noise inside the vehicle and improving driving comfort.

[0134] S6: Generate airborne sound by combining the acoustic-acoustic transfer function and the source load.

[0135] Among them, airborne sound refers to noise transmitted through the air, which is usually radiated directly into the air by the sound source and propagated to the receiving point through the air medium.

[0136] In a possible implementation manner, the airborne sound is specifically:

[0137]

[0138]

[0139]

[0140] Among them, p b Indicates air sound, L f It represents the noise value of the cab noise in the 1 / 3 octave band of the center frequency f, i = 1, 2, K, n, n represents the total number of center frequencies, k i It represents the energy ratio of the ith cab sound source to the cab noise in the 1 / 3 octave band of the center frequency f, L if and R if They represent the sound power level and sound insulation of the ith cab sound source in the 1 / 3 octave band of the center frequency f, L mf and R mfThey represent the sound power level and sound insulation of the engine in the 1 / 3 octave band of the center frequency f, L ff and R ff They represent the sound power level and sound insulation of the cooling system in the 1 / 3 octave band of the center frequency f, L cf and R cf They represent the sound power level and sound insulation of the transmission parts in the 1 / 3 octave band of the center frequency f, L yf and R yf They represent the sound power level and sound insulation of hydraulic components in the 1 / 3 octave band of the center frequency f, L ef and R ef They represent the sound power level and sound insulation of the exhaust in the 1 / 3 octave band of the central frequency f, L af and R af They respectively represent the sound power level and sound insulation of the intake air in the 1 / 3 octave band of the center frequency f.

[0141] It should be noted that by combining the sound-to-sound transfer function and the sound source load to generate airborne sound, the direct impact of the sound source on the cab noise can be accurately evaluated, and targeted sound insulation measures can be taken in noise control to improve the acoustic environment and driving comfort in the car.

[0142] S7: Synthesize the cab noise based on structure-borne sound and airborne sound.

[0143] Among them, cab noise refers to the noise that enters the cab through air transmission or structural transmission during the operation of the vehicle. These noises mainly come from the engine, transmission system, intake and exhaust system, cooling system, and the contact between tires and the ground.

[0144] In a possible implementation manner, the cab noise is specifically:

[0145] p=p a +p b

[0146] Where p represents the cab noise, p a represents structure-borne sound, p b Indicates air sound.

[0147] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0148] In the present invention, by obtaining the vibration-acoustic transfer function and the sound-acoustic transfer function, the noise transfer path can be effectively analyzed, the noise transfer characteristics of each noise source can be accurately predicted, the contribution of different cab sound sources can be identified, the control ability of the cab noise is improved, and the specific influence of each component on the cab noise can be clearly displayed. By establishing a cab model, a vehicle dynamics model and a vehicle statistical energy model, the cab noise level under different working conditions can be simulated in the design stage, the noise level can be estimated, the improvement demand for physical prototypes can be reduced, and development costs and time can be saved. The cab noise prediction is achieved through model simulation technology, which does not rely on the experimental testing of physical prototypes, avoids the testing and rectification work after the prototype is offline, saves product development costs, shortens the product development cycle, reduces the testing cost, and significantly improves the development efficiency.

[0149] It should be noted that by synthesizing the cab noise, the actual noise environment in the cab can be comprehensively evaluated, providing an accurate basis for the acoustic design of the entire vehicle, identifying and optimizing the main noise sources, and improving passenger comfort and the acoustic performance of the vehicle.

[0150] Reference Manual Attached Figure 7 , showing a schematic structural diagram of a cab noise prediction system provided by the present invention.

[0151] The present invention further provides a cab noise prediction system 20, which is applied to the above-mentioned cab noise prediction method, comprising:

[0152] Processor 201.

[0153] The memory 202 stores computer-readable instructions. When the computer-readable instructions are executed by the processor 201 , the method for predicting cab noise in the method embodiment is implemented.

[0154] The cab noise prediction system 20 provided by the present invention can execute the above-mentioned cab noise prediction method and achieve the same or similar technical effects. To avoid repetition, the present invention will not elaborate on them.

[0155] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0156] In the present invention, by obtaining the vibration-acoustic transfer function and the sound-acoustic transfer function, the noise transfer path can be effectively analyzed, the noise transfer characteristics of each noise source can be accurately predicted, the contribution of different cab sound sources can be identified, the control ability of the cab noise is improved, and the specific influence of each component on the cab noise can be clearly displayed. By establishing a cab model, a vehicle dynamics model and a vehicle statistical energy model, the cab noise level under different working conditions can be simulated in the design stage, the noise level can be estimated, the improvement demand for physical prototypes can be reduced, and development costs and time can be saved. The cab noise prediction is achieved through model simulation technology, which does not rely on the experimental testing of physical prototypes, avoids the testing and rectification work after the prototype is offline, saves product development costs, shortens the product development cycle, reduces the testing cost, and significantly improves the development efficiency.

[0157] It should be understood that the processor in the embodiment of the present invention may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0158] It should also be understood that the memory in the embodiments of the present invention may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of random access memory (RAM) are available, such as static RAM (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link DRAM (SLDRAM), and direct rambus RAM (DR RAM).

[0159] The above embodiments can be implemented in whole or in part by software, hardware (such as circuits), firmware or any other combination. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When a computer instruction or computer program is loaded or executed on a computer, a process or function according to an embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. Computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that contains one or more available media sets. The available medium can be a magnetic medium (for example, a floppy disk, a hard disk, a tape), an optical medium (for example, a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state hard disk.

[0160] It should be understood that the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship, but it may also indicate an "and / or" relationship. Please refer to the context for specific understanding.

[0161] In the present invention, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0162] It should be understood that in various embodiments of the present invention, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0163] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0164] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described equipment, devices and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0165] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0166] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0167] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0168] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0169] An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the method for predicting cab noise according to the method embodiment is implemented.

[0170] A computer-readable storage medium provided by the present invention can implement the steps and effects of the method for predicting cab noise in the above method embodiment, and to avoid repetition, the present invention will not go into details.

[0171] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0172] In the present invention, by obtaining the vibration-acoustic transfer function and the acoustic-acoustic transfer function, the noise transfer path can be effectively analyzed, the noise transfer characteristics of each noise source can be accurately predicted, the contribution of different cab sound sources can be identified, the control ability of cab noise can be improved, and the specific influence of each component on cab noise can be clearly displayed. By establishing a cab model, a vehicle dynamics model, and a vehicle statistical energy model, the cab noise level under different working conditions can be simulated in the design stage, the noise level can be estimated, the improvement requirements of the physical prototype can be reduced, and the development cost and time can be saved. The cab noise prediction is realized through the model simulation technology, which does not rely on the test test of the physical prototype, and the test rectification work after the prototype is offline is avoided, which saves product development costs, shortens the product development cycle, reduces the test cost, and significantly improves the development efficiency. .

[0173] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

[0174] There are a few points to note:

[0175] (1) The drawings of the embodiments of the present invention only relate to the structures related to the embodiments of the present invention, and other structures may refer to the general design.

[0176] (2) For the sake of clarity, in the drawings used to describe the embodiments of the present invention, the thickness of the layers or regions is exaggerated or reduced, that is, these drawings are not drawn according to the actual scale. It is understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element or there may be intermediate elements.

[0177] (3) In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to obtain new embodiments.

[0178] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for predicting cab noise, characterized in that: include: S1: Obtain the vibration-acoustic transfer function from each cab suspension point to the driver's position; S2: Obtain the suspension point load under different working conditions; S3: Obtaining the sound-to-sound transfer function from the cab sound source to the driver's position; S4: performing a sound power level test on the cab sound source to obtain a sound source load of the cab sound source, wherein the cab sound source includes an engine, a cooling system, an exhaust system, an air intake system, a hydraulic component, and a transmission component; S5: generating structure-borne sound by combining the vibration-acoustic transfer function and the suspension point load; S6: generating airborne sound by combining the acoustic-to-acoustic transfer function and the sound source load; S7: Synthesize the cab noise according to the structure-borne sound and the airborne sound.

2. The method for predicting cab noise according to claim 1, characterized in that: When there is a real cab, S1 is specifically: The vibration-acoustic transfer function from each cab suspension point to the driver's position is obtained by hammering method, vibration exciter method and volume sound source test method; When there is only a cab model, S1 specifically includes: S101: establishing a finite element model of the cab by using finite element software, simplifying the cab model and performing finite element meshing, and assigning material properties and thickness properties to each panel of the cab; S102: With the goal of establishing a cab TB model, various panels are connected in combination with the cab welding point model and corresponding connection units; S103: Establishing a cab acoustic cavity model; S104: coupling the cab TB model and the cab acoustic cavity model to obtain a coupling model; S105: in the coupling model, applying sweep frequency excitation along multiple directions of each cab suspension point to simulate the vibration transmission path from each cab suspension point to the driver's position under actual working conditions; S106: Determine the vibration-acoustic transfer function from each cab suspension point to the driver's position using a solver.

3. The method for predicting cab noise according to claim 1, characterized in that: When there is a physical cab, S2 specifically includes: S201: Setting the range of the analysis frequency width when collecting the suspension point load: f min <f b <f max Among them, f min represents the lower limit of the analysis frequency, f b Indicates the analysis frequency width, f max Indicates the upper limit of the analysis frequency; S202: collecting the loads of the active side of the suspension point and the passive side of the suspension point respectively according to predefined working conditions within the range of the analysis frequency width, and obtaining the loads of the suspension point under different working conditions; When there is only a cab model, S2 specifically includes: S201: Use dynamics software to establish a vehicle dynamics model based on the topological relationship, hard point location, mass properties, kinematic pairs, elastic element characteristics, and damping element characteristics of key vehicle components; S202: Acquire vehicle elastic component parameters according to the vehicle dynamics model, and perform flexibility processing on the cab; S203: Establishing a rigid-flexible coupling dynamics model of the whole vehicle based on the whole vehicle dynamics model, combined with vehicle elastic component parameters, the flexible cab, and structural characteristics and motion relationships of various vehicle systems; S204: Obtain the suspension point loads under different working conditions through the rigid-flexible coupling dynamics model of the whole vehicle.

4. The method for predicting cab noise according to claim 1, characterized in that: When there is a physical cab, S3 specifically includes: S301: arranging a volume sound source in the cab, and measuring a volume acceleration of the volume sound source; S302: placing microphones at various cab sound sources, and measuring sound pressure values ​​of various cab sound sources using the microphones; S303: Obtain an acoustic-acoustic transfer function according to the volume acceleration and the sound pressure value: L Wf =P Wf -R wf in, represents the acoustic transfer function, R Wf P represents the energy-based sound insulation of the vehicle cab to the cab sound source W in the 1 / 3 octave band of the center frequency f, wf It represents the sound pressure value in the 1 / 3 octave band of the center frequency f measured by the microphone at the sound source W in the cab, Q f R represents the volume acceleration of a volume sound source in a frequency band 1 / 3 octave of the center frequency f. wf It represents the average sound insulation from the cab sound source W to the cab in the 1 / 3 octave band with the center frequency f, R if It represents the sound insulation from the i-th surface of the cab sound source W to the cab in the 1 / 3 octave band of the center frequency f, L Wf It represents the contribution of the cab sound source W to the A-weighted sound pressure level in the cab in the 1 / 3 octave band with the center frequency f.

5. The method for predicting cab noise according to claim 1, characterized in that: When there is only a cab model, S3 specifically includes: S301: Establishing a vehicle statistical energy model using statistical energy analysis software; S302: Dividing the vehicle into a plurality of coupled subsystems by using the whole vehicle statistical energy model, and establishing a subsystem model; S303: Generate internal and external field acoustic cavities using the subsystem model, and define internal loss factors, coupling loss factors and modal density parameters of each subsystem; S304: applying sound power excitation or volume acceleration excitation near the sound source of the cab; S305: Obtain the acoustic transfer function from the cab sound source to the driver's position by converting the acoustic power excitation and the volume acceleration excitation: Where Q is the volume acceleration and L is the sound power level.

6. The method for predicting cab noise according to claim 1, characterized in that: The sound source loads include engine sound source loads, cooling system sound source loads, exhaust sound source loads, intake sound source loads, hydraulic component sound source loads and transmission component sound source loads; The S4 specifically includes: S401: determining engine speed data, engine torque data, cooling system speed data, cooling system torque data, exhaust system speed data, exhaust system torque data, intake system speed data, intake system torque data, hydraulic component speed data, hydraulic component torque data, transmission component speed data, and transmission component torque data according to the speed data and torque data; S402: performing a sound power level test by using an engine bench test according to the engine speed data and the engine torque data to obtain an engine sound source load; S403: performing a sound power level test using a cooling system bench test according to the cooling system speed data and the cooling system torque data to obtain a cooling system sound source load; S404: performing a sound power level test by using an exhaust bench test according to the exhaust system speed data and the exhaust system torque data to obtain an exhaust sound source load; S405: performing a sound power level test by using an intake bench test according to the intake system speed data and the intake system torque data to obtain an intake sound source load; S406: performing a sound power level test through a hydraulic component bench test according to the hydraulic component rotation speed data and the hydraulic component torque data to obtain a sound source load of the hydraulic component; S407: According to the transmission component rotation speed data and the transmission component torque data, a sound power level test is performed through a transmission component bench test to obtain a transmission component sound source load.

7. The method for predicting cab noise according to claim 1, characterized in that: The structure-borne sound is specifically: Among them, p a Indicates structure-borne sound, F pi represents the suspension point load of the ith suspension point, NTF i represents the vibration-acoustic transfer function of the i-th suspension point, i=1, 2, ..., n, and n represents the total number of suspension points.

8. The method for predicting cab noise according to claim 7, characterized in that: The air sound is specifically: Among them, p b Indicates air sound, L f represents the noise value of the cab noise in the 1 / 3 octave band of the center frequency f, i = 1, 2, ..., n, n represents the total number of center frequencies, k i It represents the energy ratio of the ith cab sound source to the cab noise in the 1 / 3 octave band of the center frequency f, L if and R if They represent the sound power level and sound insulation of the ith cab sound source in the 1 / 3 octave band of the center frequency f, L mf and R mf They represent the sound power level and sound insulation of the engine in the 1 / 3 octave band of the center frequency f, L ff and R ff They represent the sound power level and sound insulation of the cooling system in the 1 / 3 octave band of the center frequency f, L cf and R cf They represent the sound power level and sound insulation of the transmission parts in the 1 / 3 octave band of the center frequency f, L yf and R yf They represent the sound power level and sound insulation of hydraulic components in the 1 / 3 octave band of the center frequency f, L ef and R ef They represent the sound power level and sound insulation of the exhaust in the 1 / 3 octave band of the central frequency f, L af and R af They respectively represent the sound power level and sound insulation of the intake air in the 1 / 3 octave band of the center frequency f.

9. The method for predicting cab noise according to claim 1, characterized in that: The cab noise is specifically: p=p a +p b Where p represents the cab noise, p a represents structure-borne sound, p b Indicates air sound.

10. A prediction system for cab noise, characterized in that: include: processor; A memory having computer-readable instructions stored thereon, wherein when the computer-readable instructions are executed by the processor, the method for predicting cabin noise according to any one of claims 1 to 9 is implemented.

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