Method and device for analyzing transmission characteristics of vibration and noise from a heat source to a heat shield

Abstract

The application discloses a heat shield vibration and noise transmission characteristic analysis method and device. When a set excitation force is applied to a vehicle heat source body in a non-starting state, a first vibration frequency response curve, a second vibration frequency response curve and a first noise frequency response curve are picked up by a first vibration acceleration sensor arranged on the vehicle heat source body, a second vibration acceleration sensor arranged on a heat shield corresponding to the vehicle heat source body and a microphone arranged in front of the heat shield. When a set excitation force is applied to the heat shield in the non-starting state, a third vibration frequency response curve and a second noise frequency response curve are picked up by the second vibration acceleration sensor and the microphone. The transmission characteristic of the heat shield to vibration at the heat source is analyzed according to the first vibration frequency response curve and the second vibration frequency response curve. The application realizes the analysis of the amplification property of the heat shield to vibration and noise at the heat source.

Description

Technical Field

[0001] The present invention belongs to the technical field of NVH performance test, evaluation and analysis of automotive heat shields and dust shields, and particularly relates to a method and device for analyzing the transmission characteristics of a heat shield to vibration and noise at a heat source. Background Art

[0002] Temperatures near a car's powertrain, supercharger, and exhaust system are high, reaching as high as 700°C near the supercharger. Due to the compact layout of various automotive systems and the rubber-made components of piping and wiring harnesses, heat shields are essential. They are typically used around superchargers, exhaust pipes, and fuel lines. Heat shields typically provide thermal insulation, insulation, waterproofing, and flame retardancy.

[0003] Automotive heat shields are typically rigidly fixed to the heat source side, such as the exhaust system or brake disc. Heat shields are typically made of aluminum-coated steel or single-layer steel, with a thickness of 0.5cm-2.0cm. These thin-walled panels easily amplify vibration and noise excitation at the heat source, causing noise problems. Due to high temperatures and proximity to rotating components, ordinary sensors cannot meet near-field testing requirements. High-temperature-resistant sensors that meet these requirements are often large, making them difficult to place in the limited space near the vehicle's powertrain / exhaust system / brake disc. Furthermore, high-temperature-resistant sensors are expensive and have limited application scenarios, so few manufacturers purchase them. Therefore, testing and analyzing the vibration and noise transmission characteristics of heat shields at heat sources has always been difficult, and few manufacturers have conducted such tests. Summary of the Invention

[0004] In response to the problems existing in the prior art, the present invention provides a method and device for analyzing the transmission characteristics of a heat shield to vibration and noise at a heat source, which aims to solve the problem of difficulty in identifying the amplification properties of the heat shield to vibration and noise at a heat source.

[0005] In order to solve the above technical problems, the present invention is implemented through the following technical solutions:

[0006] According to a first aspect of the present invention, a method for analyzing the transfer characteristics of a heat shield to vibration and noise at a heat source is provided, comprising:

[0007] obtaining a first vibration frequency response curve, a second vibration frequency response curve, and a first noise frequency response curve, respectively picked up by a first vibration acceleration sensor provided on the heat source body of the vehicle, a second vibration acceleration sensor provided on a heat shield corresponding to the heat source body of the vehicle, and a microphone provided in front of the heat shield, when a set excitation force is applied to the heat source body of the vehicle in a non-starting state;

[0008] obtaining a third vibration frequency response curve and a second noise frequency response curve picked up by the second vibration acceleration sensor and the microphone respectively when the automobile is in a non-starting state and applies excitation to the heat shield using the set excitation force;

[0009] analyzing the transmission characteristics of the heat shield to the vibration at the heat source according to the first vibration frequency response curve and the second vibration frequency response curve;

[0010] The transfer characteristics of the heat shield to the noise at the heat source are analyzed based on the third vibration frequency response curve, the first noise frequency response curve, and the second noise frequency response curve.

[0011] In a possible implementation of the first aspect, analyzing the transfer characteristics of the heat shield to the vibration at the heat source based on the first vibration frequency response curve and the second vibration frequency response curve is specifically as follows:

[0012] comparing the first vibration frequency response curve and the second vibration frequency response curve based on frequency;

[0013] The difference in vibration amplitude at the same frequency is the transmission characteristic of the heat shield to the vibration at the heat source.

[0014] In a possible implementation of the first aspect, analyzing the transfer characteristics of the heat shield to noise at the heat source based on the third vibration frequency response curve, the first noise frequency response curve, and the second noise frequency response curve is specifically as follows:

[0015] comparing the third vibration frequency response curve, the first noise frequency response curve, and the second noise frequency response curve based on frequency;

[0016] The noise peak at the same frequency is the transfer characteristic of the heat shield to the noise at the heat source.

[0017] In a possible implementation of the first aspect, the second vibration acceleration sensor is disposed at the geometric center of the maximum radiation surface of the heat shield, and the first vibration acceleration sensor is disposed at a projection position of the second vibration acceleration sensor on the automobile heat source body.

[0018] In a possible implementation of the first aspect, the microphone is located 4 cm to 6 cm in front of a geometric center of a maximum radiation surface of the heat shield.

[0019] In a possible implementation of the first aspect, the set excitation force is 30±2N, and the frequency range is 20Hz to 5000Hz.

[0020] According to a second aspect of the present invention, there is provided a device for analyzing the transmission characteristics of a heat shield to vibration and noise at a heat source, comprising:

[0021] a first acquisition module for acquiring, when a set excitation force is applied to a heat source body of the vehicle by the vehicle in a non-starting state, a first vibration frequency response curve, a second vibration frequency response curve, and a first noise frequency response curve, respectively picked up by a first vibration acceleration sensor provided on the heat source body of the vehicle, a second vibration acceleration sensor provided on a heat shield corresponding to the heat source body of the vehicle, and a microphone provided in front of the heat shield;

[0022] a second acquisition module, configured to acquire a third vibration frequency response curve and a second noise frequency response curve picked up by the second vibration acceleration sensor and the microphone respectively when the automobile is in a non-starting state and the heat shield is excited by the set excitation force;

[0023] a first analysis module, configured to analyze the transmission characteristics of the heat shield to the vibration at the heat source based on the first vibration frequency response curve and the second vibration frequency response curve;

[0024] The second analysis module is configured to analyze the transfer characteristics of the heat shield to the noise at the heat source based on the third vibration frequency response curve, the first noise frequency response curve, and the second noise frequency response curve.

[0025] Compared with the prior art, the present invention has at least the following beneficial effects:

[0026] The present invention provides a method for analyzing the transfer characteristics of a heat insulation cover to vibration and noise at a heat source. The method comprises the following steps: obtaining a first vibration frequency response curve, a second vibration frequency response curve, and a first noise frequency response curve picked up by a first vibration acceleration sensor provided on the heat source body of the vehicle, a second vibration acceleration sensor provided on the heat insulation cover corresponding to the heat source body of the vehicle, and a microphone provided in front of the heat insulation cover when a set excitation force is applied to the heat source body of the vehicle in a non-starting state; and obtaining a third vibration frequency response curve and a second noise frequency response curve picked up by the second vibration acceleration sensor and the microphone when a set excitation force is applied to the heat insulation cover in a non-starting state. Finally, based on the first vibration frequency response curve and the second vibration frequency response curve, the transfer characteristics of the heat insulation cover to vibration at the heat source are analyzed; and based on the third vibration frequency response curve, the first noise frequency response curve, and the second noise frequency response curve, the transfer characteristics of the heat insulation cover to noise at the heat source are analyzed. That is, the data obtained in the analysis method of the present invention is relevant data when the vehicle powertrain is not started and the vehicle is stationary, which avoids the limitations of high temperature conditions and rotating parts on the working conditions of the sensor. Conventional vibration acceleration sensors and microphones are used to pick up responses to the heat source and the heat shield. At the same time, testing is carried out under the boundaries of the actual vehicle, which is more conducive to the reproduction and identification of actual vehicle problems. Through comparative analysis of vibration and noise in the frequency domain, the amplification properties of the heat shield on the vibration at the heat source and the corresponding vibration problems are identified.

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the specific embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the specific embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0029] Figure 1 This is a flow chart of a method for analyzing the transfer characteristics of a heat shield to vibration and noise at a heat source according to an embodiment of the present invention;

[0030] Figure 2 A side view of the installation position of the vibration acceleration sensor and microphone according to an embodiment of the present invention;

[0031] Figure 3 This is a front view of the installation position of the vibration acceleration sensor and microphone according to an embodiment of the present invention;

[0032] Figure 4is the first vibration frequency response curve V1 of the embodiment of the present invention;

[0033] Figure 5 is the second vibration frequency response curve V2 of the embodiment of the present invention;

[0034] Figure 6 is a first noise frequency response curve S1 according to an embodiment of the present invention;

[0035] Figure 7 is the third vibration frequency response curve V3 of the embodiment of the present invention;

[0036] Figure 8 is a second noise frequency response curve S2 according to an embodiment of the present invention;

[0037] Figure 9 This is the amplification curve of the heat source vibration by the heat shield according to the embodiment of the present invention;

[0038] Figure 10 A diagram showing a frequency comparison between a first vibration frequency response curve V1 and a first noise frequency response curve S1 according to an embodiment of the present invention;

[0039] Figure 11 1 is a diagram comparing the first noise frequency response curve S1, the second noise frequency response curve S2 and the third vibration frequency response curve V3 according to an embodiment of the present invention.

[0040] In the figure: 1-heat source body; 2-heat insulation cover; 3-first vibration acceleration sensor; 4-second vibration acceleration sensor; 5-microphone; 6-heat insulation cover mounting bracket; 7-excitation point position. DETAILED DESCRIPTION

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0042] like Figure 1 As shown, an embodiment of the present invention provides a method for analyzing the transmission characteristics of a heat shield to vibration and noise at a heat source, which specifically includes the following steps:

[0043] S101. Obtain a first vibration frequency response curve, a second vibration frequency response curve, and a first noise frequency response curve, respectively picked up by a first vibration acceleration sensor provided on the automobile heat source body, a second vibration acceleration sensor provided on a heat insulation cover corresponding to the automobile heat source body, and a microphone provided in front of the heat insulation cover, when a set excitation force is applied to the automobile heat source body in a non-starting state.

[0044] It should be noted that a vibration frequency response curve describes the frequency response characteristics of a structure under vibration. It reflects the vibration characteristics of a structure at different excitation frequencies. A noise frequency response curve describes the response of noise at various frequencies. It is often used to indicate the noise levels of various noise sources at different frequencies.

[0045] For example, the vibration frequency response curve is picked up by the vibration acceleration sensor, specifically:

[0046] a1. Install the vibration accelerometer: Install the vibration accelerometer on the object to be tested (the vehicle heat source body H and the corresponding heat shield of the vehicle heat source body), ensuring that it is firmly installed and will not fall off or loosen due to vibration;

[0047] b1. Data collection: The vibration data of the object at different frequencies is collected and recorded through the vibration acceleration sensor;

[0048] c1. Data Analysis: Perform spectrum analysis on the collected vibration data to obtain a vibration frequency response curve. Spectrum analysis can be performed using software or hardware methods, such as fast Fourier transform (FFT).

[0049] For example, the noise frequency response curve picked up by the microphone is specifically:

[0050] a2. Install the microphone: Install the microphone near the sound source to be tested (in front of the heat shield corresponding to the vehicle heat source body), ensuring that it is firmly installed and will not move or loosen due to sound waves.

[0051] b2. Data collection: Use a microphone to collect noise data from the sound source at different frequencies and record it.

[0052] c2. Data Analysis: Perform spectrum analysis on the collected data to obtain the noise frequency response curve. Spectrum analysis can be performed using software or hardware methods, such as fast Fourier transform (FFT).

[0053] S102: Obtain a third vibration frequency response curve and a second noise frequency response curve respectively picked up by the second vibration acceleration sensor and the microphone when the automobile is in a non-starting state and applies excitation to the heat shield using the set excitation force.

[0054] S103, analyzing the transmission characteristic of the heat shield to vibration at the heat source according to the first vibration frequency response curve and the second vibration frequency response curve.

[0055] In the embodiment, the analyzing the transmission characteristic of the heat shield to vibration at the heat source according to the first vibration frequency response curve and the second vibration frequency response curve in step S103 can be realized by the following way:

[0056] comparing the first vibration frequency response curve and the second vibration frequency response curve based on frequency;

[0057] The vibration amplitude difference at the same frequency is the transmission characteristic of the heat shield to vibration at the heat source.

[0058] S104, analyzing the transmission characteristic of the heat shield to noise at the heat source according to the third vibration frequency response curve, the first noise frequency response curve and the second noise frequency response curve.

[0059] In the embodiment, the analyzing the transmission characteristic of the heat shield to noise at the heat source according to the third vibration frequency response curve, the first noise frequency response curve and the second noise frequency response curve in step S104 can be realized by the following way:

[0060] comparing the third vibration frequency response curve, the first noise frequency response curve and the second noise frequency response curve based on frequency;

[0061] The noise peak value at the same frequency is the transmission characteristic of the heat shield to noise at the heat source.

[0062] In an embodiment, in combination with Figure 2 and Figure 3 As shown in the figures, the second vibration acceleration sensor 4 is arranged at the geometric center position of the maximum radiation surface of the heat shield 2, and the first vibration acceleration sensor 3 is arranged at the projection position of the second vibration acceleration sensor 4 on the automobile heat source body 1.

[0063] In an embodiment, in combination with Figure 2 As shown in the figures, the microphone 5 is arranged at a position 4-6 cm in front of the geometric center position of the maximum radiation surface of the heat shield 2. For example, the microphone 5 is arranged at a position 5 cm in front of the geometric center position of the maximum radiation surface of the heat shield 2.

[0064] Preferably, the set excitation force is 30±2 N, and the frequency range is 20-5000 Hz. For example, a force hammer is used to apply the excitation force.

[0065] It should also be noted that automotive dust covers are typically used near rotating parts such as brake discs, primarily to dissipate heat and block foreign matter. During normal vehicle operation, the temperature of the brake disc is typically above 50°C. The analysis method of this invention can also be used to test and analyze the vibration and noise transmission characteristics of the dust cover at heat sources.

[0066] The following is a more detailed explanation of the method for analyzing the transmission characteristics of the heat shield to the vibration and noise at the heat source in conjunction with the embodiments of the present invention. The specific process is as follows:

[0067] 1. Test object and environment

[0068] 1.1 With the vehicle parked on level ground, determine the location of the heat shield to be tested.

[0069] 1.2 Sensor layout (combined Figure 2 and Figure 3 ):

[0070] 1.2.1 Arrange a vibration acceleration sensor at the geometric center of the maximum radiation surface of the heat shield 2, named the second vibration acceleration sensor 4, and connect the wires to the data acquisition device;

[0071] 1.2.2 Place microphone 5 5 mm from the geometric center of the maximum radiation surface of heat shield 2. The height of microphone 5 should be the same as the geometric center of heat shield 2. Connect the wires to the data acquisition device.

[0072] 1.2.3 Arrange a vibration acceleration sensor at the projection position of the second vibration acceleration sensor 4 on the installation object (heat source body 1) thereof (heat insulation cover), name it the first vibration acceleration sensor 3, and connect the wires to the data collector.

[0073] 1.3 A harder hammer head is selected for the force hammer, and a fixed-amplitude broadband pulse excitation input is applied to the heat source body 1 by the force hammer to ensure that the excitation frequency can cover the excitation frequency of the heat source body where the heat shield is located, and fully reflect the actual excitation received by the heat shield.

[0074] 1.4 Select the geometric center of the plane opposite to the surface where the heat shield is installed, and mark it as the excitation input point, that is, excitation point position 7.

[0075] 1.5 Confirm the hammer input force and determine it based on the actual excitation force amplitude of the system where the heat source is located. For comparison purposes, 30N is recommended.

[0076] 2. Testing and analysis steps

[0077] 2.1 Parameter settings: The excitation force is 30±2N, the frequency range is defined as 20Hz-5000Hz, the resolution is 1Hz, the input signal is windowed with force, the output signal is windowed with exponential, the average number is ≥20, and the noise channel is not weighted.

[0078] 2.2 Incentive Definition:

[0079] 2.2.1 The first incentive:

[0080] Use a hammer to set the force amplitude to stimulate the excitation point position 7 of the heat source body 1, see Figure 4 and Figure 5 As shown, the first vibration acceleration sensor 3 and the second vibration acceleration sensor 4 respectively pick up the vibration frequency response curves of the excitation force to their own positions, which are the first vibration frequency response curve V1 and the second vibration frequency response curve V2 respectively; see Figure 6 As shown, the first noise frequency response curve S1 of the microphone 5 picking up the excitation force to its own position;

[0081] 2.2.2 Second incentive:

[0082] Use a hammer to stimulate the sensor near the geometric center of the heat shield 2 (as close to the geometric center as possible) with a set force amplitude, see Figure 7 As shown, the third vibration frequency response curve V3 of the second vibration acceleration sensor 4 picking up the excitation force to its own position; see Figure 8 As shown, the microphone picks up the second noise frequency response curve S2 at its own position.

[0083] 2.3 Data Analysis

[0084] 2.3.1 See Figure 9 As shown, the first vibration frequency response curve V1 and the second vibration frequency response curve V2 are compared in the frequency domain: the difference in vibration amplitude between the two is the amplification curve of the heat insulation cover to the heat source vibration (that is, the transfer characteristic of the heat insulation cover to the vibration at the heat source), which is recorded and saved.

[0085] 2.3.2 The first noise frequency response curve S1 is the noise radiation curve of the heat shield under unit force, which should be recorded and saved.

[0086] 2.3.4 Further analysis:

[0087] 2.3.4.1 See Figure 10 As shown, the first vibration frequency response curve V1 and the first noise frequency response curve S1 are compared based on frequency. The noise peak at the same frequency can be considered to be caused by the vibration of the heat source;

[0088] 2.3.4.2 See Figure 11As shown, by comparing the first noise frequency response curve S1, the second noise frequency response curve S2 and the third vibration frequency response curve V3, the noise peak at the same frequency can be considered to be caused by the mode under the constraint boundary of the heat insulation cover, that is, the transmission characteristic of the heat insulation cover to the noise at the heat source.

[0089] 2.3.4.3 The verification based on the analysis in 2.3.4.1 and 2.3.4.2 can be verified by applying disturbances to the heat source body or heat shield, for example, using the added mass method to change the modal frequency of the heat source body or heat shield, and then repeating the test (performed in accordance with 2.1 and 2.2) and analysis (performed in accordance with 2.3.4).

[0090] In this embodiment, the method for analyzing the transmission characteristics of the heat shield to the vibration and noise at the heat source uses static boundary testing instead of dynamic testing to avoid the restrictions of high temperature conditions and rotating parts on the operating conditions of the sensor. Based on the test under the actual vehicle boundary, the actual operating boundary of the heat shield / dust cover is maintained, which is more conducive to the reproduction and identification of real vehicle problems. A hammer is used to apply a fixed-amplitude broadband pulse excitation input to the heat source body to ensure that the excitation frequency can cover the excitation frequency of the heat source where the heat shield / dust cover is located, fully reflecting the actual excitation of the heat shield / dust cover. Conventional vibration acceleration sensors and microphones are used to pick up the responses of the heat source and the heat shield / dust cover. Compared with high-temperature resistant sensors, these conventional vibration acceleration sensors require less space, are easy to obtain, and are low-cost. The decomposition of a high-temperature / small-space experiment involving rotating parts into a conventional experiment not restricted by temperature / space / rotating parts reduces the difficulty and cost of the experiment and forms a stable and reliable experimental procedure.

[0091] Based on the analysis method of this embodiment, several suggestions are made for the design of automotive heat shields / dust shields from the perspective of reducing vibration and noise radiation:

[0092] ① Considering that the excitation source of vibration and noise generated by automotive heat insulation covers / dust covers is the heat source itself, from the perspective of reducing vibration and noise transmission, the heat insulation cover / dust cover should be fixed away from the heat source itself and installed on the system that requires insulation, that is, the non-active vibration source.

[0093] ② Considering that the vibration and noise generated by automotive heat shields / dust shields are caused by the noise radiation caused by the low stiffness and low modality of thin-walled sheet metal, it is recommended that the heat shield / dust shield and the heat source body have as many connection points as possible, and it is recommended that there be at least one connection point on every 50mm x 50mm plane. At the same time, the heat shield / dust shield body needs to be optimized or reinforced to ensure that the minimum dynamic stiffness at each point is higher than 250N / mm and the first-order surface mode is higher than 300Hz (the maximum speed of the internal combustion engine is 6000r / min, and its second-order excitation is up to 300Hz). These two measures are key means to improve its stiffness mode while keeping the sheet metal thickness unchanged.

[0094] An embodiment of the present invention provides a device for analyzing the transfer characteristics of a heat shield to vibration and noise at a heat source, comprising a first acquisition module, a second acquisition module, a first analysis module, and a second analysis module, wherein each module is configured as follows:

[0095] The first acquisition module is used to obtain a first vibration frequency response curve, a second vibration frequency response curve, and a first noise frequency response curve, which are picked up by a first vibration acceleration sensor provided on the automobile heat source body, a second vibration acceleration sensor provided on a heat insulation cover corresponding to the automobile heat source body, and a microphone provided in front of the heat insulation cover when the automobile applies excitation to the automobile heat source body with a set excitation force in a non-starting state.

[0096] The second acquisition module is configured to acquire a third vibration frequency response curve and a second noise frequency response curve picked up by the second vibration acceleration sensor and the microphone respectively when the automobile applies excitation to the heat shield with the set excitation force in a non-starting state.

[0097] The first analysis module is configured to analyze the transmission characteristics of the heat shield to the vibration at the heat source according to the first vibration frequency response curve and the second vibration frequency response curve.

[0098] The second analysis module is configured to analyze the transfer characteristics of the heat shield to the noise at the heat source based on the third vibration frequency response curve, the first noise frequency response curve, and the second noise frequency response curve.

[0099] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the above-described embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-described embodiments within the technical scope disclosed by the present invention, or replace some of the technical features therein with equivalents. Such modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in 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.

Claims

1. A method for analyzing the transmission characteristics of a heat shield to vibration and noise at a heat source, characterized in that: include: obtaining a first vibration frequency response curve, a second vibration frequency response curve, and a first noise frequency response curve, respectively picked up by a first vibration acceleration sensor provided on the heat source body of the vehicle, a second vibration acceleration sensor provided on a heat shield corresponding to the heat source body of the vehicle, and a microphone provided in front of the heat shield, when a set excitation force is applied to the heat source body of the vehicle in a non-starting state; obtaining a third vibration frequency response curve and a second noise frequency response curve picked up by the second vibration acceleration sensor and the microphone respectively when the automobile is in a non-starting state and applies excitation to the heat shield using the set excitation force; analyzing the transmission characteristics of the heat shield to the vibration at the heat source according to the first vibration frequency response curve and the second vibration frequency response curve; The transfer characteristics of the heat shield to the noise at the heat source are analyzed based on the third vibration frequency response curve, the first noise frequency response curve, and the second noise frequency response curve.

2. The method for analyzing the transmission characteristics of the heat shield to the vibration and noise at the heat source according to claim 1, characterized in that: The analysis of the transfer characteristics of the heat shield to the vibration at the heat source based on the first vibration frequency response curve and the second vibration frequency response curve is specifically as follows: comparing the first vibration frequency response curve and the second vibration frequency response curve based on frequency; The difference in vibration amplitude at the same frequency is the transmission characteristic of the heat shield to the vibration at the heat source.

3. The method for analyzing the transmission characteristics of the heat shield to the vibration and noise at the heat source according to claim 1, characterized in that: The analysis of the transfer characteristics of the heat shield to the noise at the heat source based on the third vibration frequency response curve, the first noise frequency response curve, and the second noise frequency response curve is specifically as follows: comparing the third vibration frequency response curve, the first noise frequency response curve, and the second noise frequency response curve based on frequency; The noise peak at the same frequency is the transfer characteristic of the heat shield to the noise at the heat source.

4. The method for analyzing the transmission characteristics of a heat shield to vibration and noise at a heat source according to claim 1, characterized in that: The second vibration acceleration sensor is arranged at the geometric center position of the maximum radiation surface of the heat shield, and the first vibration acceleration sensor is arranged at the projection position of the second vibration acceleration sensor on the automobile heat source body.

5. The method for analyzing the transmission characteristics of the heat shield to the vibration and noise at the heat source according to claim 1, characterized in that: The microphone is arranged 4 cm to 6 cm in front of the geometric center of the maximum radiation surface of the heat shield.

6. The method for analyzing the transmission characteristics of a heat shield to vibration and noise at a heat source according to claim 1, characterized in that: The excitation force is set to 30±2N, and the frequency range is 20Hz to 5000Hz.

7. A device for analyzing the transmission characteristics of a heat shield to vibration and noise at a heat source, characterized in that: include: a first acquisition module for acquiring, when a set excitation force is applied to a heat source body of the vehicle by the vehicle in a non-starting state, a first vibration frequency response curve, a second vibration frequency response curve, and a first noise frequency response curve, respectively picked up by a first vibration acceleration sensor provided on the heat source body of the vehicle, a second vibration acceleration sensor provided on a heat shield corresponding to the heat source body of the vehicle, and a microphone provided in front of the heat shield; a second acquisition module, configured to acquire a third vibration frequency response curve and a second noise frequency response curve picked up by the second vibration acceleration sensor and the microphone respectively when the automobile is in a non-starting state and the heat shield is excited by the set excitation force; a first analysis module, configured to analyze the transmission characteristics of the heat shield to the vibration at the heat source based on the first vibration frequency response curve and the second vibration frequency response curve; The second analysis module is configured to analyze the transfer characteristics of the heat shield to the noise at the heat source based on the third vibration frequency response curve, the first noise frequency response curve, and the second noise frequency response curve.

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