A method and system for predicting cab noise

Abstract

The present invention provides a method and system for predicting cab noise, relating to the technical field of vehicle strength analysis. The method comprises: when a physical cab or a cab model is available, obtaining the vibration-acoustic transfer function from each cab mounting point to the driver's position through different methods, obtaining the mounting point load under different operating conditions, obtaining the sound-acoustic transfer function from the cab sound source to the driver's position through different methods, and performing sound power level testing on each cab sound source to obtain the sound source load of the cab sound source; combining the vibration-acoustic transfer function and the mounting point load to generate structure-borne sound; combining the sound-acoustic transfer function and the cab sound source load to generate airborne sound; and synthesizing the cab noise based on the structure-borne sound and airborne sound. The present invention can more quickly and accurately determine cab noise.

Description

Technical Field

[0001] The present 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 and combine it with vibration source analysis, acoustic transfer path analysis (TPA), multi-physics field coupling simulation, and experimental data correction to simulate and predict the noise level within the vehicle. This can identify noise sources and transmission paths, help optimize the acoustic environment during the design phase, and thus improve driving comfort and reduce the noise impact on drivers and passengers.

[0003] Effective noise prediction can identify and resolve potential noise issues in the early stages of design, thereby improving the overall quality of the vehicle and ensuring a healthy and pleasant experience for drivers and passengers. Cabin noise prediction can enhance driving comfort and safety, meet noise regulations, enhance vehicle market competitiveness, shorten R&D cycles, 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 various components 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. This 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 in the prior art that the existing noise prediction methods cannot accurately identify the specific impact of the noise sources of various components on the overall noise of the cab, lack effective noise transmission path analysis, and are difficult to accurately predict and control the 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, the present invention provides a method and system for predicting cab noise.

[0006] The technical solutions provided by the embodiments of the present invention are 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 acoustic-acoustic 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, hydraulic components, and transmission components;

[0013] S5: generating structure-borne sound by combining the vibro-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 based on 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] The 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 having a computer program stored thereon. 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 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 the cab noise is improved, and the specific impact of each component on the cab noise is 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 phase, the noise level can be estimated, the need for improvement of the physical prototype 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 the physical prototype, 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 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 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 at 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 measurement points in the cab for an acoustic-to-acoustic transfer function test according to an embodiment of the present invention;

[0029] Figure 5 A schematic diagram of a cab transfer function test in 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 cab noise prediction system 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 an "exemplary" in the present invention should not be interpreted as being preferred or advantageous over other embodiments or designs. Rather, the use of the word "exemplary" is intended to present concepts in a concrete manner. Furthermore, in the embodiments of the present invention, "and / or" can mean both or either of the two.

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

[0035] Reference Manual 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 fields 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 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, 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 applying instantaneous force (such as knocking) to the structure using an impact hammer, 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 to excite the sound field and measure the response of the structure to sound transfer. It 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, when there is only a cab model, S1 specifically includes:

[0044] S101: Establish a finite element model of the cab using finite element software, simplify the cab model and perform finite element meshing, and assign material properties and thickness properties 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 the 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 a finite element model of the cab using 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] The cab TB model is a simplified structural model typically used to analyze torsional and bending behavior. In finite element analysis of the cab, the TB model can represent the cab's overall stiffness and strength characteristics, helping to analyze its response under dynamic loads. The weld point model, used in finite element analysis, models the weld points at the connections between cab components (such as panels) to reflect their connection strength and stiffness. These weld points are often a significant factor influencing structural strength. Connection elements are used in finite element models to simulate the connection between different components and can reflect the properties of the connection, such as stiffness and damping.

[0049] It should be noted that by combining the weld point model and the corresponding connection units to connect the various panels 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] 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 the interior of 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: Couple the cab TB model and the cab acoustic cavity model to obtain a coupled model.

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

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

[0055] Among them, swept frequency excitation is a testing 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 coupled 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 resonant 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, helping 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 Figure 2 , shows a schematic diagram of load testing of various suspension points of the cab provided by an embodiment of the present invention.

[0062] like Figure 2, is a schematic diagram of the load test of each cab suspension point, 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 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 , is a simulation diagram of the vehicle cab suspension point load, including the cab, suspension point load and working condition loading, showing the connection structure between the cab and the frame, as well as the distribution of the suspension point load under simulated working conditions (with working condition loading).

[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 entire 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, 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]

[0070] Among them, f min Indicates 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 on the active side and the passive side of the suspension point according to predefined working conditions within the range of the analysis frequency width to obtain the suspension point loads under different working conditions;

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

[0073] S201: Using dynamics software, establish a vehicle dynamics model based on the topological relationships, hard point locations, 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 positions 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 the 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 modes of movement between two components that connect and constrain them, such as hinges and sliding, which affect the relative movement between components. Elastic element characteristics refer to the characteristics of components such as the vehicle suspension system that deform after being subjected to force and can return to their original shape, 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 through mechanisms such as friction or fluid resistance during movement, 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: Obtain vehicle elastic component parameters based on the vehicle dynamics model and perform 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 the 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 during the modeling process, the rigid components of the vehicle (such as the frame, body, etc.) are regarded as components with a certain degree of flexibility, and their deformation and dynamic behavior under stress are simulated 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, taking into account 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 dynamic model of the entire 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 vehicle's comfort and noise control performance in actual use.

[0082] Reference Manual Figure 4 , shows a schematic diagram of the arrangement of measurement points in the acoustic-to-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 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 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 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 engine combustion out of the vehicle, usually including components such as exhaust manifold, catalytic converter, and muffler. The intake system is responsible for introducing air into the engine for combustion. Hydraulic components are used to control various mechanical movements and are 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 clutch, transmission, drive shaft and differential.

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

[0087] S301: placing 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 using the microphone;

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

[0090]

[0091]

[0092]

[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 with 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 the volume sound source in the 1 / 3 octave band of the center frequency f. wf R 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. if L represents the sound insulation from the i-th surface of the cab sound source W to the cab in the 1 / 3 octave band with the center frequency f, 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 operating 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 vibroacoustic 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 multiple coupled subsystems using a vehicle statistical energy model, and establish subsystem models.

[0099] Among them, coupled subsystems refer to the decomposition of complex vehicle structures 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 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 energy gradually decreases 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 vehicle's acoustic performance and optimize the sound insulation design.

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

[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 excites 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: Based on the sound power level and volume acceleration excitation, the sound-to-sound transfer function from the cab sound source to the driver's position is obtained:

[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 transmission path and load distribution of the suspension points under different working conditions, and thus optimize the design of the suspension system, effectively reduce the transmission of vibration 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 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 a 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). It 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 the 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 the 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, which indicates the output power and load size.

[0119] S402: Based on the engine speed data and the engine torque data, a sound power level test is performed using an engine bench test 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 testing 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 on the cooling system bench test based on the cooling system speed data and the cooling system torque data to obtain the cooling system sound source load.

[0122] S404: Based on the exhaust system speed data and the exhaust system torque data, a sound power level test is performed using an exhaust bench test to obtain the exhaust sound source load.

[0123] S405: Based on the intake system speed data and the intake system torque data, a sound power level test is performed using an intake bench test to obtain an intake sound source load.

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

[0125] S407: Perform a sound power level test on the transmission component through a bench test based on the transmission component speed data and the transmission component torque data to obtain a sound source load on the transmission component.

[0126] Reference Manual 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). The vibration of each suspension point is accumulated to the target point through the 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 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. Structure-borne sound is usually caused by vibration sources, such as the engine, transmission system or impact caused by 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 i-th suspension point, NTF i represents the vibration-acoustic transfer function of the ith suspension point, , n represents the total number of suspension points.

[0133] It should be noted that combining the vibration-acoustic transfer function and suspension point loads 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 interior noise and improving driving comfort.

[0134] S6: Generate airborne sound by combining the acoustic-acoustic transfer function and the sound 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 transmitted to the receiving point through the air medium.

[0136] In a possible implementation, 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 with the center frequency f. , n represents the total number of center frequencies, k i L represents the energy ratio of the i-th cab sound source to the cab noise in the 1 / 3 octave band with the center frequency f. if and R if They represent the sound power level and sound insulation of the i-th cab sound source in the 1 / 3 octave band with 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 central frequency f, L cf and R cf They represent the sound power level and sound insulation of the transmission components 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 with 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 with the center frequency f.

[0141] It should be noted that by combining the sound-to-noise transfer function and the sound source load to generate airborne sound, the direct impact of the sound source on the cabin 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 vehicle.

[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 structure-borne transmission during the operation of the vehicle. This noise mainly comes from the engine, transmission system, intake and exhaust system, cooling system, and the contact between tires and the ground.

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

[0145]

[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 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 the cab noise is improved, and the specific impact of each component on the cab noise is 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 phase, the noise level can be estimated, the need for improvement of the physical prototype 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 the physical prototype, 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 development efficiency.

[0149] It should be noted that by synthesizing 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 Figure 7 , which shows a structural schematic 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 cabin noise according to 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 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 the cab noise is improved, and the specific impact of each component on the cab noise is 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 phase, the noise level can be estimated, the need for improvement of the physical prototype 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 the physical prototype, 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 development efficiency.

[0157] It should be understood that the processor in the embodiments of the present invention may be a central processing unit (CPU), but 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 any conventional processor, etc.

[0158] It should also be understood that the memory in the embodiments of the present invention may be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory may be 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 SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), and direct rambus RAM (DR RAM).

[0159] The above embodiments can be implemented in whole or in part via software, hardware (e.g., circuits), firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented in whole or in part in the form of a computer program product. A computer program product comprises one or more computer instructions or computer programs. When the computer instructions or computer program are loaded or executed on a computer, the processes or functions according to the embodiments of the present invention are fully or partially generated. 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. For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired means (e.g., infrared, wireless, microwave, etc.). A computer-readable storage medium can be any available medium accessible by a computer or a data storage device such as a server or data center that contains a collection of one or more available media. Available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media. Semiconductor media can be solid-state drives.

[0160] It should be understood that the term "and / or" as used herein simply describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A alone, A and B together, or B alone. A and B can be singular or plural. Furthermore, the character " / " as used herein generally indicates an "or" relationship between the associated objects, but it may also indicate an "and / or" relationship. For specific understanding, please refer to the context.

[0161] In this disclosure, "at least one" means one or more, and "plurality" 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 mean: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or plural.

[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. Professionals and technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0164] Those skilled in the art will 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 merely illustrative. For example, the division of units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. In addition, 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, and can be electrical, mechanical, or other forms.

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

[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 a function is implemented as 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 portion that contributes to the prior art, or the portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the method of the present invention. The aforementioned storage medium includes various media that can store program code, such as USB flash drives, mobile hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[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 cabin noise according to the method embodiment is implemented.

[0170] The 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. To avoid repetition, the present invention will not elaborate on them.

[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 the cab noise is improved, and the specific impact of each component on the cab noise is 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 phase, the noise level can be estimated, the need for improvement of the physical prototype 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 the physical prototype, 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 development efficiency.

[0173] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection 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. Other structures may refer to conventional designs.

[0176] (2) For the sake of clarity, the thickness of layers or regions in the drawings used to describe the embodiments of the present invention are exaggerated or reduced, that is, these drawings are not drawn to 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 intervening elements may be present.

[0177] (3) In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to form 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 acoustic-acoustic 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, hydraulic components, and transmission components; S5: generating structure-borne sound by combining the vibro-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: synthesizing cab noise based on the structure-borne sound and the airborne sound; Wherein, the S3 specifically includes: S301: placing a volume sound source in the cab and measuring the volume acceleration of the volume sound source; S302: placing microphones at each cab sound source, and measuring the sound pressure value of each cab sound source using the microphones; S303: Obtain an acoustic-to-acoustic transfer function according to the volume acceleration and the sound pressure value: ； ； ； 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 with 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 the volume sound source in the 1 / 3 octave band of the center frequency f. wf R 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. if L represents the sound insulation from the i-th surface of the cab sound source W to the cab in the 1 / 3 octave band with the center frequency f, 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.

2. The method for predicting cab noise according to claim 1, characterized in that: When there is a physical cab, S1 is specifically: The vibration-acoustic transfer function from each cab suspension point to the driver's position is obtained through 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 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, connect each panel by combining the cab weld point model and the corresponding connection unit; S103: Establishing a cab acoustic cavity model; S104: coupling the cab TB model and the cab acoustic cavity model to obtain a coupled model; S105: In the coupling model, applying swept 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: ； Among them, f min Indicates 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 on the active side and the passive side of the suspension point according to predefined working conditions within the range of the analysis frequency width to obtain the suspension point loads under different working conditions; When there is only a cab model, S2 specifically includes: S201: Using dynamics software, establish a vehicle dynamics model based on the topological relationships, hard point locations, mass properties, kinematic pairs, elastic element characteristics, and damping element characteristics of key vehicle components; S202: Obtaining vehicle elastic component parameters according to the vehicle dynamics model, and performing flexibility processing on the cab; S203: Establishing a rigid-flexible coupling dynamic model of the vehicle based on the vehicle dynamics model, combined with vehicle elastic component parameters, the flexible cab, and the structural characteristics and motion relationships of various vehicle systems; S204: Obtaining the suspension point loads under different working conditions through the rigid-flexible coupling dynamic model of the entire vehicle.

4. 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 multiple coupled subsystems using the vehicle statistical energy model and establishing subsystem models; 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; S304: Applying sound power excitation or volume acceleration excitation near the cab sound source; S305: Obtain the acoustic-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.

5. 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 based on the speed data and torque data; S402: Performing a sound power level test using an engine bench test based on the engine speed data and the engine torque data to obtain an engine sound source load; S403: performing a sound power level test on a cooling system bench test according to the cooling system speed data and the cooling system torque data to obtain a sound source load of the cooling system; S404: performing a sound power level test using an exhaust bench test based on 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 using an intake bench test based on 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 on a hydraulic component bench test based on the hydraulic component speed data and the hydraulic component torque data to obtain a sound source load of the hydraulic component; S407: Performing a sound power level test on a transmission component bench test according to the transmission component speed data and the transmission component torque data to obtain a sound source load on the transmission component.

6. 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 i-th suspension point, NTF i represents the vibration-acoustic transfer function of the ith suspension point, , n represents the total number of suspension points.

7. The method for predicting cab noise according to claim 6, characterized in that: The airborne sound is specifically: ； ； ； Among them, p b Indicates air sound, L f It represents the noise value of the cab noise in the 1 / 3 octave band with the center frequency f. , n represents the total number of center frequencies, k i L represents the energy ratio of the i-th cab sound source to the cab noise in the 1 / 3 octave band with the center frequency f. if and R if They represent the sound power level and sound insulation of the i-th cab sound source in the 1 / 3 octave band with 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 central frequency f, L cf and R cf They represent the sound power level and sound insulation of the transmission components 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 with 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 with the center frequency f.

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

9. A cab noise prediction system, 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 8 is implemented.

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