A torsional damper NVH performance evaluation method

Abstract

This invention belongs to the field of automotive technology, specifically a method for evaluating the NVH performance of a torsional vibration damper. It includes the following steps: Step 1, test preparation; Step 2, data collection under different operating conditions; Step 3, data processing; and Step 4, evaluation of the NVH performance of the torsional vibration damper. After obtaining the rotational speed signal of the torsional vibration damper, this invention analyzes the NVH mechanism of the transmission system and the user's vehicle usage scenarios to design whole-vehicle NVH test conditions for the damper, formulates test data processing methods and objective evaluation indicators, and uses this method to guide the evaluation of the damper's NVH performance.

Description

Technical Field

[0001] This invention belongs to the field of automotive technology, specifically a method for evaluating the NVH performance of torsional dampers. Background Technology

[0002] Torsional dampers are the main components for attenuating the torsional excitation of an engine. Therefore, the development of damper NVH is an important part of the development of drivetrain NVH performance, which mainly includes preliminary simulation calculations and physical prototype vehicle testing and verification.

[0003] Existing NVH-related test methods for vibration dampers mainly focus on how to obtain the rotational speed signal of torsional vibration dampers, and do not involve test methods for specific testing procedures. Summary of the Invention

[0004] To address the aforementioned issues, this invention provides a method for evaluating the NVH performance of a torsional damper. After acquiring the rotational speed signal of the torsional damper, the method analyzes the NVH mechanism of the transmission system and the user's vehicle usage scenarios, designs the vehicle NVH test conditions for the damper, and formulates test data processing methods and objective evaluation indicators. This method can guide the evaluation of the NVH performance of the damper.

[0005] The technical solution of this invention is described below in conjunction with the accompanying drawings:

[0006] A method for evaluating the NVH performance of a torsional vibration damper includes the following steps:

[0007] Step 1: Prepare for the experiment;

[0008] Step 2: Collect data under different operating conditions;

[0009] Step 3: Process the test data;

[0010] Step 4: Evaluate the NVH performance of the torsional vibration damper.

[0011] Furthermore, the specific method for step one is as follows:

[0012] 11) Arrange the sensors;

[0013] 12) Obtain vehicle driving signals;

[0014] 13) Set up the test software.

[0015] Furthermore, the specific method for step 11) is as follows:

[0016] The sensors include a front-end speed sensor and a rear-end speed sensor of the torsional damper; the geometric center of the end face of the front-end speed sensor is aligned with the axial centerline of the engine start gear ring; the end face of the rear-end speed sensor is aligned with the axial centerline of the transmission input shaft gear; the front-end speed sensor and the rear-end speed sensor of the torsional damper are connected to a data acquisition device;

[0017] Add vibration and noise measurement points for the steering wheel, seat rails, and front and rear rows inside the vehicle to test the overall vibration and noise performance of the torsional damper. Connect the test sensors to the data acquisition equipment.

[0018] Furthermore, the specific method for step 12) is as follows:

[0019] Vehicle driving signals include engine speed, transmission gear, accelerator pedal opening, vehicle speed, and engine coolant temperature; connect the vehicle driving signals to the data acquisition equipment.

[0020] Furthermore, the specific method for step 13) is as follows:

[0021] Configure the sensor channel type, power supply method, sensitivity, and sampling frequency.

[0022] Furthermore, the specific method for step two is as follows:

[0023] The test vehicle must be warmed up to reach an engine coolant temperature of 90±5℃. After the engine is warmed up, it will be tested under the following conditions: start-up, shutdown, stationary idling, idling charging, creeping, and full-load acceleration.

[0024] Furthermore, the start-up and shutdown test is as follows: For models where the engine can be started and shut down manually, a fixed-condition start-up and shutdown test is performed, and the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal are recorded throughout the process, recording 6 sets of valid data;

[0025] For vehicles whose engines cannot be started or stopped manually, tests are conducted by rapidly pressing and releasing the accelerator pedal or other methods that allow the engine to start or stop normally during driving. The engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal are recorded throughout the process, and 6 sets of valid data are recorded.

[0026] During the data acquisition process, simultaneously evaluate whether there are any issues related to the shock absorber, such as flywheel or transmission knocking noises and impact vibrations.

[0027] The test for the fixed idling condition is as follows: For models that can enter the fixed idling condition, the engine is stabilized at the idle speed, and the transmission is placed in neutral for manual transmission models or P, R, N and D for automatic transmission models. The engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal are recorded throughout the process. Each set of data is recorded for 30 seconds, and 3 sets of valid data are recorded.

[0028] During the data acquisition process, simultaneously evaluate whether there are any issues related to the shock absorbers, such as flywheel knocking noises, transmission knocking noises, and vehicle vibrations.

[0029] The test for the idling charging condition is as follows:

[0030] For hybrid vehicles that can enter the idling charging condition, the engine is kept in a stable charging state, the transmission is in P gear, and the engine crankshaft or flywheel speed pulse signal and transmission input shaft speed pulse signal are recorded throughout the process. Each set of data is recorded for 30 seconds, and 3 sets of valid data are recorded.

[0031] During the data acquisition process, simultaneously evaluate whether there are any issues related to the shock absorber, such as flywheel or transmission knocking noises, booming sounds, and vehicle vibrations.

[0032] The test for the creeping condition is as follows:

[0033] For models where the engine can directly drive the vehicle to crawl, the engine is stabilized at idle speed, and the accelerator pedal and brake pedal are released to make the vehicle stabilize at the minimum speed and drive slowly. The engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal are recorded throughout the process. Each set of data is recorded for 30 seconds, and 3 sets of valid data are recorded.

[0034] During the data acquisition process, the presence of issues related to the shock absorber, such as transmission knocking noise, booming, and vehicle vibration, is evaluated simultaneously.

[0035] The full-load acceleration test is as follows:

[0036] For vehicles with multi-gear transmissions that can fix gears, test the engine speed from the lowest stable speed to the highest engine speed or the speed corresponding to a vehicle speed of 130km / h under full-load acceleration conditions in each gear. Record the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal throughout the process. For vehicles with an independent rear final reducer, synchronously collect the rear final reducer input shaft speed pulse signal and record 3 sets of valid data.

[0037] For vehicles with multi-gear transmissions or single-gear transmissions that cannot be fixed in gear, place the transmission in D gear and test the acceleration from the lowest stable speed to 130km / h under full load conditions. Record the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal throughout the process, and record 3 sets of valid data.

[0038] If the testing conditions of a semi-anechoic chamber chassis dynamometer are available during this test, the hub load should be set to a 5% slope condition. During road testing, test roads with a 5% slope should be selected as much as possible to simulate the more severe load conditions of the transmission system in user scenarios.

[0039] Furthermore, the specific method for step three is as follows:

[0040] The test data processing for the start-up and shutdown conditions is as follows:

[0041] The curve of the damper's torsional angle changing with time is calculated by integrating the difference between the engine crankshaft or flywheel speed and the transmission input shaft speed.

[0042] The test data processing for the fixed idling condition is as follows:

[0043] Calculate the time-varying curves of the engine's main order speed fluctuations and the transmission input shaft.

[0044] The test data processing for the idling charging condition is as follows:

[0045] Calculate the time-varying curves of the engine's main order speed fluctuations and the transmission input shaft.

[0046] The test data for the creeping condition is processed as follows:

[0047] Calculate the time-varying curves of the engine's main order speed fluctuations and the transmission input shaft.

[0048] The test data processing for the full-load acceleration condition is as follows:

[0049] Calculate the curves of engine crankshaft or flywheel and transmission input shaft speed fluctuations over time or with engine speed.

[0050] Furthermore, the specific method for step four is as follows:

[0051] During start-up and shutdown, the curve of the damper torsion angle changing with time is used to evaluate whether the torsional damper spring is compressed to its maximum stroke.

[0052] Under stationary idling conditions, the vibration isolation performance of the torsional damper is evaluated by the time-varying curves of the engine's main order speed fluctuations at the engine crankshaft or flywheel and transmission input shaft.

[0053] During idling charging, the vibration isolation performance of the damper and whether the torsional mode of the transmission system is coupled with the engine excitation are evaluated by the time-varying curves of the engine crankshaft or flywheel and transmission input shaft.

[0054] During creeping operation, the vibration isolation performance of the damper and whether the torsional mode of the transmission system is coupled with the engine excitation are evaluated by the time-varying curves of the engine crankshaft or flywheel and transmission input shaft.

[0055] Under full-load acceleration conditions, the vibration isolation performance of the damper and whether the torsional mode of the transmission system is coupled with the engine excitation are evaluated by the curves of the engine crankshaft or flywheel and transmission input shaft speed fluctuations over time or with engine speed.

[0056] The beneficial effects of this invention are as follows:

[0057] 1) After obtaining the speed signal of the torsional damper, by analyzing the NVH mechanism of the transmission system and the user's usage scenarios of the vehicle, the whole vehicle NVH test conditions of the damper are designed, and test data processing methods and objective evaluation indicators are formulated. This method can guide the evaluation of the NVH performance of the damper.

[0058] 2) This invention is applicable to all vehicle types, including fuel vehicles and hybrid vehicles, that are equipped with torsional dampers. Attached Figure Description

[0059] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0060] Figure 1 This is a schematic diagram of the process of the present invention;

[0061] Figure 2a , Figure 2b This is a schematic diagram showing the installation location of the speed sensor. Detailed Implementation

[0062] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0064] Example 1

[0065] See Figure 1 This invention provides a method for evaluating the NVH performance of a torsional vibration damper, comprising the following steps:

[0066] Step 1: Prepare for the experiment;

[0067] The specific method is as follows:

[0068] 11) Arrange the sensors;

[0069] See Figure 2a and Figure 2b The sensors include a front-end speed sensor and a rear-end speed sensor of the torsional damper;

[0070] The speed at the front end of the torsional damper can be measured by drilling a hole in the engine flywheel housing and installing a Hall speed sensor. The geometric center of the sensor end face should be aligned with the axial center line of the engine starter gear ring. Alternatively, the crankshaft speed can be obtained by connecting the signal line of the engine crankshaft position sensor.

[0071] The speed at the rear end of the torsional damper can be measured by drilling holes in the transmission housing to install a Hall effect speed sensor to test the speed of the transmission input shaft gear. The geometric center of the sensor end face should be aligned with the centerline of the transmission input shaft gear axis. Alternatively, the signal line of the transmission's built-in input shaft speed sensor can be connected to obtain the speed. In addition, vibration measurement points for the steering wheel, seat rails, and front and rear row noise can be added to test the overall vehicle vibration and noise performance of the torsional damper. These sensors can be connected to data acquisition equipment via connecting cables.

[0072] 12) Obtain vehicle driving signals;

[0073] Connect the vehicle's CAN signal to the data acquisition equipment via an adapter cable to collect signals such as engine speed, transmission gear, accelerator pedal opening, vehicle speed, and engine coolant temperature.

[0074] 13) Set up the test software.

[0075] Configure the sensor channel type, power supply method, sensitivity, and sampling frequency to complete the test preparation.

[0076] Step 2: Collect data under different operating conditions;

[0077] The specific method is as follows:

[0078] The test vehicle must be warmed up to reach an engine coolant temperature of 90±5℃. After the engine is warmed up, it will be tested under the following conditions: start-up, shutdown, stationary idling, idling charging, creeping, and full-load acceleration.

[0079] The start-up and shutdown test is as follows: For models whose engines can be started and shut down manually, a fixed-condition start-up and shutdown test is performed, and the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal are recorded throughout the process, and 6 sets of valid data are recorded.

[0080] For models whose engines cannot be started or stopped manually, tests are conducted by rapidly pressing and releasing the accelerator pedal or other methods that allow the vehicle to start or stop normally while driving. The engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal are recorded throughout the process, and 6 sets of valid data are recorded.

[0081] During the data acquisition process, simultaneously evaluate whether there are any issues related to the shock absorber, such as flywheel or transmission knocking noises and impact vibrations.

[0082] The test for the fixed idling condition is as follows: For models that can enter the fixed idling condition, the engine is stabilized at the idle speed, and the transmission is placed in neutral for manual transmission models or P, R, N and D for automatic transmission models. The engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal are recorded throughout the process. Each set of data is recorded for 30 seconds, and 3 sets of valid data are recorded.

[0083] During the data acquisition process, simultaneously evaluate whether there are any issues related to the shock absorbers, such as flywheel knocking noises, transmission knocking noises, and vehicle vibrations.

[0084] The test for the idling charging condition is as follows:

[0085] For hybrid vehicles that can enter the idling charging condition, the engine is kept in a stable charging state, the transmission is in P gear, and the engine crankshaft or flywheel speed pulse signal and transmission input shaft speed pulse signal are recorded throughout the process. Each set of data is recorded for 30 seconds, and 3 sets of valid data are recorded.

[0086] During the data acquisition process, simultaneously evaluate whether there are any issues related to the shock absorber, such as flywheel or transmission knocking noises, booming sounds, and vehicle vibrations.

[0087] The test for the creeping condition is as follows:

[0088] For models where the engine can directly drive the vehicle to crawl, the engine is stabilized at idle speed, and the accelerator pedal and brake pedal are released to make the vehicle stabilize at the minimum speed and drive slowly. The engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal are recorded throughout the process. Each set of data is recorded for 30 seconds, and 3 sets of valid data are recorded.

[0089] During the data acquisition process, the presence of issues related to the shock absorber, such as transmission knocking noise, booming, and vehicle vibration, is evaluated simultaneously.

[0090] The full-load acceleration test is as follows:

[0091] For vehicles with multi-gear transmissions that can fix gears, test the engine speed from the lowest stable speed to the highest engine speed or the speed corresponding to a vehicle speed of 130km / h under full-load acceleration conditions in each gear. Record the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal throughout the process. For vehicles with an independent rear final reducer, synchronously collect the rear final reducer input shaft speed pulse signal and record 3 sets of valid data.

[0092] For vehicles with multi-gear transmissions or single-gear transmissions that cannot be fixed in gear, place the transmission in D gear and test the acceleration from the lowest stable speed to 130km / h under full load conditions. Record the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal throughout the process, and record 3 sets of valid data.

[0093] If the testing conditions of a semi-anechoic chamber chassis dynamometer are available during this test, the hub load should be set to a 5% slope condition. During road testing, test roads with a 5% slope should be selected as much as possible to simulate the more severe load conditions of the transmission system in user scenarios.

[0094] Step 3: Process the test data;

[0095] The specific method is as follows:

[0096] The test data processing for the start-up and shutdown conditions is as follows:

[0097] The curve of the damper's torsional angle changing over time is calculated by integrating the difference between the engine crankshaft or flywheel speed and the transmission input shaft speed. The unit is °.

[0098] The test data processing for the fixed idling condition is as follows:

[0099] Calculate the time-varying curves of the engine's main-order speed fluctuations for the engine crankshaft or flywheel and transmission input shaft, in rad / s. 2 ;

[0100] The test data processing for the idling charging condition is as follows:

[0101] Calculate the time-varying curves of the engine's main-order speed fluctuations for the engine crankshaft or flywheel and transmission input shaft, in rad / s. 2 ;

[0102] The test data for the creeping condition is processed as follows:

[0103] Calculate the time-varying curves of the engine's main-order speed fluctuations for the engine crankshaft or flywheel and transmission input shaft, in rad / s. 2 ;

[0104] The test data processing for the full-load acceleration condition is as follows:

[0105] Calculate the curves of engine crankshaft or flywheel and transmission input shaft speed fluctuations over time or with engine speed, in rad / s. 2 .

[0106] Step 4: Evaluate the NVH performance of the torsional vibration damper.

[0107] The specific method is as follows:

[0108] Based on the comparison of the test data processing results with the target, and combined with the objective test results of in-vehicle vibration and noise, a comprehensive evaluation of the NVH performance of the shock absorber is conducted.

[0109] During start-up and shutdown, the curve of the damper torsion angle changing with time is used to evaluate whether the torsional damper spring is compressed to its maximum stroke.

[0110] Under stationary idling conditions, the vibration isolation performance of the torsional damper is evaluated by the time-varying curves of the engine's main order speed fluctuations at the engine crankshaft or flywheel and transmission input shaft.

[0111] During idling charging, the vibration isolation performance of the damper and whether the torsional mode of the transmission system is coupled with the engine excitation are evaluated by the time-varying curves of the engine crankshaft or flywheel and transmission input shaft.

[0112] During creeping operation, the vibration isolation performance of the damper and whether the torsional mode of the transmission system is coupled with the engine excitation are evaluated by the time-varying curves of the engine crankshaft or flywheel and transmission input shaft.

[0113] Under full-load acceleration conditions, the vibration isolation performance of the damper and whether the torsional mode of the transmission system is coupled with the engine excitation are evaluated by the curves of the engine crankshaft or flywheel and transmission input shaft speed fluctuations over time or with engine speed.

[0114] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. It can be applied to various fields suitable for the invention. Further modifications can be readily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A method for evaluating the NVH performance of a torsional vibration damper, characterized in that, Includes the following steps: Step 1: Prepare for the experiment; Step 2: Collect data under different operating conditions; Step 3: Process the test data; Step 4: Evaluate the NVH performance of the torsional vibration damper; The specific method for step two is as follows: The test vehicle must be warmed up and driven until the engine coolant temperature reaches 90±5℃. After the engine is warmed up, the following conditions are tested: start-up, shutdown, stationary idling, idling charging, creeping, and full-load acceleration. The tests for the start-up and shutdown conditions are as follows: For vehicle models that can start and stop the engine manually, conduct fixed-condition start and stop tests; For vehicles whose engines cannot be started or stopped manually, tests can be conducted by rapidly pressing and releasing the accelerator pedal while driving, or by other methods that allow the engine to start or stop normally. The test for the fixed idling condition is as follows: For models that can enter the fixed idling condition, the engine is stabilized at the idle speed, and the transmission is respectively placed in neutral for manual transmission models or in P, R, N and D gears for automatic transmission models. The test for the idling charging condition is as follows: For hybrid vehicles that can enter the idling charging mode, the engine is kept in a stable charging state and the transmission is in P gear. The test for the creeping condition is as follows: For models where the engine can directly drive the vehicle to crawl, keep the engine at idle speed and release the accelerator and brake pedals to keep the vehicle moving slowly at the minimum speed. The full-load acceleration test is as follows: For vehicles with multi-gear transmissions that can fix gears, test the engine speed in each gear under full-load acceleration conditions from the lowest stable speed to the highest engine speed or the speed corresponding to a vehicle speed of 130 km / h. For vehicles with multi-gear transmissions or single-gear transmissions that cannot be fixed in gear, place the transmission in D gear and test the acceleration from the lowest stable speed to 130 km / h under full load conditions. When testing under full-load acceleration conditions, if the testing conditions of a semi-anechoic chamber chassis dynamometer are available, the hub load is set to a 5% slope condition. During road testing, a test road with a 0%-5% slope is selected to simulate the relatively harsh working conditions of the transmission system load in user scenarios.

2. The method for evaluating the NVH performance of a torsional vibration damper according to claim 1, characterized in that, The specific method for step one is as follows: 11) Arrange the sensors; 12) Obtain vehicle driving signals; 13) Set up the test software.

3. The method for evaluating the NVH performance of a torsional vibration damper according to claim 2, characterized in that, The specific method for step 11) is as follows: The sensors include a front-end speed sensor and a rear-end speed sensor of the torsional damper; the geometric center of the end face of the front-end speed sensor is aligned with the axial centerline of the engine start gear ring; the end face of the rear-end speed sensor is aligned with the axial centerline of the transmission input shaft gear; the front-end speed sensor and the rear-end speed sensor of the torsional damper are connected to a data acquisition device; Add vibration and noise measurement points for the steering wheel, seat rails, and front and rear rows inside the vehicle to test the overall vibration and noise performance of the torsional damper. Connect the test sensors to the data acquisition equipment.

4. The method for evaluating the NVH performance of a torsional vibration damper according to claim 2, characterized in that, The specific method for step 12) is as follows: Vehicle driving signals include engine speed, transmission gear, accelerator pedal opening, vehicle speed, and engine coolant temperature; connect the vehicle driving signals to the data acquisition equipment.

5. The NVH performance evaluation method for a torsional vibration damper according to claim 2, characterized in that, The specific method for step 13) is as follows: Configure the sensor channel type, power supply method, sensitivity, and sampling frequency.

6. The method for evaluating the NVH performance of a torsional vibration damper according to claim 1, characterized in that, During the start-up and shutdown tests: For vehicle models that can start and stop the engine manually, record the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal throughout the entire process, and record 6 sets of valid data; For models where the engine cannot be started or stopped manually, record the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal throughout the entire process, and record 6 sets of valid data. During the data acquisition process, simultaneously evaluate whether there are any issues related to the shock absorber, such as knocking noises and impact vibrations from the flywheel and transmission. During the test of the fixed idling condition: For vehicle models that can enter the stationary idling condition, record the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal throughout the entire process. Each set of data is recorded for 30 seconds, and 3 sets of valid data are recorded. During the data acquisition process, the presence of flywheel, transmission knocking noises, and vehicle vibrations related to the shock absorbers is evaluated simultaneously. During the test of the idling charging condition: For hybrid vehicles that can enter the idling charging condition, record the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal throughout the entire process. Each set of data is recorded for 30 seconds, and 3 sets of valid data are recorded. During the data acquisition process, we simultaneously evaluate whether there are any issues related to the shock absorbers, such as flywheel or transmission knocking noises, booming sounds, and vehicle vibrations. During the test of the creeping condition: For vehicle models where the engine can directly drive the vehicle to crawl, record the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal throughout the entire process. Each set of data is recorded for 30 seconds, and 3 sets of valid data are recorded. During the data acquisition process, the presence of any transmission knocking noises, booming sounds, and vehicle vibrations related to the shock absorbers is evaluated simultaneously. During the test of the full-load acceleration condition: For vehicles with multi-gear transmissions that can fix gears, record the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal throughout the entire process. For vehicles with an independent rear final drive, synchronously collect the rear final drive input shaft speed pulse signal and record 3 sets of valid data. For multi-gear transmission models or single-gear transmission models that cannot have fixed gears, record the engine crankshaft or flywheel speed pulse signal and the transmission input shaft speed pulse signal throughout the entire process, and record 3 sets of valid data.

7. The method for evaluating the NVH performance of a torsional vibration damper according to claim 1, characterized in that, The specific method for step three is as follows: The test data processing for the start-up and shutdown conditions is as follows: The curve of the damper's torsional angle changing with time is calculated by integrating the difference between the engine crankshaft or flywheel speed and the transmission input shaft speed. The test data processing for the fixed idling condition is as follows: Calculate the time-varying curves of the engine's main order speed fluctuations and the transmission input shaft. The test data processing for the idling charging condition is as follows: Calculate the time-varying curves of the engine's main order speed fluctuations and the transmission input shaft. The test data for the creeping condition is processed as follows: Calculate the time-varying curves of the engine's main order speed fluctuations and the transmission input shaft. The test data processing for the full-load acceleration condition is as follows: Calculate the curves of engine crankshaft or flywheel and transmission input shaft speed fluctuations over time or with engine speed.

8. The method for evaluating the NVH performance of a torsional vibration damper according to claim 1, characterized in that, The specific method for step four is as follows: During start-up and shutdown, the curve of the damper torsion angle changing with time is used to evaluate whether the torsional damper spring is compressed to its maximum stroke. Under stationary idling conditions, the vibration isolation performance of the torsional damper is evaluated by the time-varying curves of the engine's main order speed fluctuations at the engine crankshaft or flywheel and transmission input shaft. During idling charging, the vibration isolation performance of the damper and whether the torsional mode of the transmission system is coupled with the engine excitation are evaluated by the time-varying curves of the engine crankshaft or flywheel and transmission input shaft. During creeping operation, the vibration isolation performance of the damper and whether the torsional mode of the transmission system is coupled with the engine excitation are evaluated by the time-varying curves of the engine crankshaft or flywheel and transmission input shaft. Under full-load acceleration conditions, the vibration isolation performance of the damper and whether the torsional mode of the transmission system is coupled with the engine excitation are evaluated by the curves of the engine crankshaft or flywheel and transmission input shaft speed fluctuations over time or with engine speed.

Images