A method and apparatus for determining the dynamics of a flywheel in a half-order vibration of an engine.

Abstract

This application provides a method for determining the flywheel dynamics of an engine's half-order vibration. Three displacement sensors are arranged on the flywheel housing facing the flywheel, and the displacement signal of each sensor is collected. The displacement signal represents the change in the vertical distance between each sensor and the flywheel. Based on the displacement signal and the coordinate values ​​of the displacement sensors, a disturbance signal of the flywheel is calculated. The frequency and time of the half-order vibration are determined. Based on the disturbance signal and the frequency and time of the half-order vibration, the flywheel dynamics when the engine experiences half-order vibration are determined. According to the method provided in this application, by collecting displacement signals of the vertical distance between at least three displacement sensors and the flywheel, a disturbance signal on the flywheel plane is calculated; then, by obtaining the frequency and time of the half-order vibration, the flywheel dynamics when the half-order vibration occurs are determined.

Description

Technical Field

[0001] This application relates to the field of engine NVH, specifically to a method and apparatus for determining the flywheel dynamics of engine half-order vibration. Background Technology

[0002] As automotive performance improves, higher demands are placed on noise control. For driving comfort, requirements exist not only for noise levels but also for noise quality. The primary source of automotive noise is engine noise, and one of the key factors affecting engine noise quality is half-order vibration. Here, order refers to the number of times an event occurs per revolution of a rotating component; half-order vibration refers to the vibration that occurs half a revolution per engine revolution, that is, the vibration of the frequency component at half the engine speed. This type of vibration produces noise of poor quality, negatively impacting the driving experience.

[0003] To reduce or eliminate half-order vibrations generated during engine operation, it is necessary to understand the mechanisms underlying their occurrence. The engine's response to half-order vibrations is related to its structural characteristics; for example, it may be caused by structural features such as bearing clearances or design defects. Currently, research on engine half-order vibrations mainly involves analyzing the crankshaft and overall engine modes—that is, testing the inherent vibration characteristics of the engine's structural system—to infer the causes of half-order vibrations.

[0004] The above methods lack analysis of the relationship between engine structure and half-order vibration during engine operation, as they do not measure the relationship between engine flywheel dynamics and half-order vibration. However, since the dynamics of the flywheel during operation are difficult to measure, it is currently difficult to analyze the engine's half-order vibration by testing the engine's flywheel dynamics, thus making it impossible to accurately analyze the cause of the engine's half-order vibration. Summary of the Invention

[0005] In view of this, this application provides a method and apparatus for determining the flywheel dynamics of engine half-order vibration. By testing the flywheel dynamics when the engine experiences half-order vibration, the causes of engine half-order vibration can be analyzed more accurately.

[0006] To address the above problems, the technical solutions provided in this application are as follows:

[0007] In a first aspect, embodiments of this application provide a method for determining the flywheel dynamics of a half-order vibration of an engine, including:

[0008] At least three locations are selected on the flywheel housing of the engine, and a displacement sensor facing the flywheel is arranged at each location;

[0009] The displacement signal of each displacement sensor is collected, and the displacement signal is a displacement signal representing the change in the vertical distance between each sensor and the flywheel of the engine;

[0010] The disturbance signal of the flywheel is calculated based on the displacement signal and the coordinate value of the displacement sensor on the plane of the flywheel housing;

[0011] Determine the frequency and timing of the half-order oscillation;

[0012] Based on the disturbance signal and the frequency and time of the half-order vibration, the flywheel dynamics when the engine experiences half-order vibration are determined.

[0013] In one possible implementation, the method further includes:

[0014] Obtain the cylinder pressure signal of the engine;

[0015] Based on the cylinder pressure signal and the frequency and time of the half-order vibration, the working condition of each cylinder when the engine experiences half-order vibration is determined.

[0016] In one possible implementation, determining the frequency and time of the half-order vibration includes: determining the frequency and time of the half-order vibration based on the engine's noise signal and vibration signal.

[0017] In one possible implementation, the engine noise signal is obtained from a microphone located outside the exhaust side of the engine.

[0018] In one possible implementation, the vibration signal of the engine is obtained from an acceleration sensor located on the outer surface of a cylinder wall of the engine, at the same height as the crankshaft.

[0019] In one possible implementation, determining the frequency and time of the half-order vibration based on the engine's noise and vibration signals includes:

[0020] Wavelet analysis is performed on the noise and vibration signals of the engine. Based on the results of the wavelet analysis, the frequency and time of the half-order vibration are identified.

[0021] In one possible implementation, the cylinder pressure signal of the engine is obtained from a cylinder pressure sensor located in each cylinder of the engine.

[0022] Secondly, embodiments of this application provide a flywheel dynamic determination device for engine half-order vibration, comprising:

[0023] A position selection unit is used to select at least three positions on the flywheel housing of the engine, each position being provided with a displacement sensor facing the flywheel;

[0024] The displacement signal acquisition unit is used to acquire the displacement signal of each displacement sensor, wherein the displacement signal is a displacement signal representing the change in the vertical distance between each sensor and the flywheel of the engine;

[0025] The disturbance signal calculation unit is used to calculate the disturbance signal of the flywheel based on the displacement signal and the coordinate value of the displacement sensor on the flywheel housing plane;

[0026] The half-order vibration determination unit is used to determine the frequency and time of the occurrence of half-order vibration.

[0027] The flywheel dynamic determination unit is used to determine the flywheel dynamics when the engine experiences a half-order vibration, based on the disturbance signal and the frequency and time of the half-order vibration.

[0028] A third aspect of this application provides an apparatus, the apparatus comprising: a processor and a memory;

[0029] The memory is used to store instructions;

[0030] The processor is configured to execute the instructions in the memory and perform the method described in the first aspect.

[0031] A fourth aspect of this application provides a computer-readable storage medium storing program code or instructions that, when run on a computer, cause the computer to perform the method described in the first aspect above.

[0032] Therefore, the embodiments of this application have the following beneficial effects:

[0033] According to the method provided in this application, displacement sensors facing the flywheel are arranged at at least three positions on the flywheel housing. The displacement signal of the vertical distance between each displacement sensor and the flywheel is collected, and the displacement signals of three points on the flywheel plane are determined. Based on the displacement signals and the coordinate values ​​of the displacement sensors, the disturbance signal of the entire flywheel plane is calculated. Then, by obtaining the frequency and time when the half-order vibration actually occurs, the flywheel dynamics when the half-order vibration occurs are determined. This realizes the testing of the flywheel dynamics when the engine experiences half-order vibration, and provides a more accurate analysis of the cause of the engine's half-order vibration. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 The engine powertrain working deformation mode diagram provided in the embodiments of this application;

[0036] Figure 2 A schematic diagram of a method for determining the dynamics of a flywheel in an engine half-order vibration, provided in an embodiment of this application;

[0037] Figure 3 A conceptual diagram of the flywheel displacement sensor arrangement provided in an embodiment of this application;

[0038] Figure 4 This application provides an embodiment of the arrangement of a displacement sensor on a flywheel housing.

[0039] Figure 5 This is a diagram showing the arrangement of a flywheel displacement sensor on a 2.0L engine, as provided in an embodiment of this application.

[0040] Figure 6 The test schematic diagram provided for the embodiments of this application;

[0041] Figure 7 This is a schematic diagram of a flywheel dynamic determination device for half-order vibration of an engine, provided as an embodiment of this application. Detailed Implementation

[0042] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0043] The inventors discovered in their research that the engine's response to half-order vibrations is related to its structural characteristics, such as bearing clearances or design defects. Currently, research on engine half-order vibrations mainly involves analyzing the modes of the crankshaft and the entire engine, such as... Figure 1As shown, this figure is a modal diagram of the engine powertrain working deformation provided in an embodiment of this application; that is, by testing the inherent vibration characteristics of the engine structural system, the cause of the half-order vibration is inferred. The above method lacks analysis of the relationship between the engine structure and the occurrence of half-order vibration during engine operation, and therefore lacks analysis of the relationship between the engine flywheel dynamics and half-order vibration. However, since the dynamics of the flywheel during operation are difficult to measure, it is currently difficult to analyze the engine's half-order vibration by testing the engine's flywheel dynamics, thus making it impossible to accurately analyze the cause of the engine's half-order vibration.

[0044] Based on this, this application provides a method for determining the flywheel dynamics of engine half-order vibration. Three displacement sensors facing the flywheel are arranged on the flywheel housing, and the displacement signal of each sensor is collected. The displacement signal represents the change in the vertical distance between each sensor and the flywheel. Based on the displacement signal and the coordinate values ​​of the displacement sensors, the flywheel disturbance signal is calculated. The frequency and time of the half-order vibration are determined. Based on the disturbance signal and the frequency and time of the half-order vibration, the flywheel dynamics when the engine experiences half-order vibration are determined. According to the method provided in this application, by collecting displacement signals of the vertical distance between at least three displacement sensors and the flywheel, calculating the disturbance signal on the flywheel plane, and then obtaining the frequency and time of the half-order vibration, the flywheel dynamics when the half-order vibration occurs are determined, solving the problem that the cause of half-order vibration cannot be studied through flywheel dynamics.

[0045] To facilitate understanding of the methods provided in the embodiments of this application, the following description will be provided in conjunction with the accompanying drawings.

[0046] See Figure 2 This figure is a schematic diagram of a method for determining the flywheel dynamics of a half-order vibration of an engine according to an embodiment of this application. Figure 2 As shown, the method may include:

[0047] Step 101: Select at least three locations on the flywheel housing of the engine, and arrange a displacement sensor facing the flywheel at each location.

[0048] The displacement sensor arrangement method provided in this application arranges the displacement sensor for testing the flywheel dynamics on the flywheel housing, eliminating the influence of test bench vibration on the test results and enabling accurate testing of flywheel dynamics.

[0049] Specifically, at least three non-interference locations (i.e., locations not adjacent to other parts and not adjacent to each other) are selected on the engine flywheel housing as placement points for displacement sensors. In practical applications, there are not many places on the flywheel housing that can be drilled. If there are fewer than three displacement sensors, it is impossible to determine the flywheel's disturbance status; therefore, in this embodiment, three locations are selected as placement points. Figure 3 As shown, this figure is a conceptual diagram of the flywheel displacement sensor arrangement provided in an embodiment of this application; as Figure 4 As shown in the figure, this figure is an arrangement diagram of a displacement sensor on a flywheel housing provided in an embodiment of this application.

[0050] Step 102: Collect the displacement signal of each displacement sensor, wherein the displacement signal is a displacement signal representing the change in the vertical distance between each displacement sensor and the flywheel of the engine.

[0051] In this embodiment, the displacement signals from the three displacement sensors are named S. A S B S C The displacement signal is a function that changes with time, and here it is a function of the change of the vertical distance between each displacement sensor and the flywheel over time. The flywheel experiences slight disturbances during operation, which causes each displacement sensor to collect a different displacement signal. The displacement signals from the three displacement sensors can determine the disturbance situation of the entire surface of a flywheel.

[0052] Step 103: Calculate the disturbance signal of the flywheel based on the displacement signal and the coordinate value of the displacement sensor on the flywheel housing plane.

[0053] In this embodiment of the application, the origin of the coordinate system is the intersection of the flywheel and the crankshaft, such as... Figure 5 The diagram shown is an example of the arrangement of flywheel displacement sensors on a 2.0L engine according to an embodiment of this application. The coordinate values ​​of the three displacement sensors on the flywheel housing plane are recorded as Y... A Y B Y C Z A Z B Z C The unit is mm; for example Figure 3 As shown, in this embodiment of the application, the flywheel disturbance signal that needs to be calculated is the disturbance signal of the flywheel along the X direction (denoted as X), the disturbance signal around the Y direction (denoted as α), and the disturbance signal around the Z direction (denoted as α). Specifically, in the embodiments of this application, the displacement signal S A S B S C and the sensor's coordinates Y A Y B Y C Z A Z B Z C The above disturbance signal is calculated by performing the following formulas (1), (2), and (3):

[0054] Disturbance signal along the X direction:

[0055]

[0056] Disturbance signal around the Y direction:

[0057]

[0058] Perturbation signal around the Z direction:

[0059]

[0060] Step 104: Determine the frequency and time of the half-order vibration.

[0061] In some possible implementations, determining the frequency and time of the half-order vibration includes: determining the frequency and time of the half-order vibration based on the engine's noise signal and vibration signal.

[0062] In some possible implementations, the noise signal of the engine is obtained from a microphone located outside the exhaust side of the engine.

[0063] In some possible implementations, the vibration signal of the engine is obtained from an acceleration sensor located on the outer surface of a cylinder wall of the engine, at the same height as the crankshaft.

[0064] In this embodiment, the microphone for obtaining engine noise signals is positioned outside the engine exhaust side, at a distance of 1 meter from the exhaust side; the acceleration sensor for obtaining engine vibration signals is positioned on the outer surface of the first cylinder wall, at the same height as the crankshaft. Figure 6 As shown, this figure is a test principle diagram provided in an embodiment of this application.

[0065] In some possible implementations, determining the frequency and time of the half-order vibration based on the engine's noise and vibration signals includes:

[0066] Wavelet analysis is performed on the noise and vibration signals of the engine. Based on the results of the wavelet analysis, the frequency and time of the half-order vibration are identified.

[0067] Specifically, in the embodiments of this application, such as Figure 6 As shown, the collected test materials are converted from voltage signals to digital signals and then sent to a data processing computer for analysis. Wavelet analysis is performed on the collected engine noise and vibration signals to identify the frequency and timing of the half-order vibrations.

[0068] Step 105: Determine the flywheel dynamics when the engine experiences half-order vibration based on the disturbance signal and the frequency and time of the half-order vibration.

[0069] In some possible implementations, the method further includes the following steps:

[0070] Obtain the cylinder pressure signal of the engine;

[0071] Based on the cylinder pressure signal and the frequency and time of the half-order vibration, the working condition of each cylinder when the engine experiences half-order vibration is determined.

[0072] Specifically, the cylinder pressure signal of the engine is obtained from a cylinder pressure sensor located in each cylinder of the engine.

[0073] like Figure 6 As shown in the embodiments of this application, displacement signals, noise signals, vibration signals and cylinder pressure signals are collected. After analyzing and processing the above signals, the working conditions of each cylinder and the dynamic conditions of the flywheel when the half-order vibration occurs can be analyzed. Combined with the above data, the mechanism of the half-order vibration can be defined.

[0074] In practical applications, by inputting the data obtained from the embodiments of this application into the simulation system, the generation of half-order vibration can be simulated based on the flywheel dynamics and the working conditions of each cylinder when the half-order vibration occurs. By adjusting other parameters, the disturbance of the flywheel in the simulation system can be reduced, making it weaker than the disturbance of the flywheel when the half-order vibration actually occurs in the test. This helps to find the direction for optimizing the structural design and achieve the reduction or elimination of the half-order phenomenon.

[0075] Based on the above method embodiments, this application provides an analysis device for engine half-order vibration, see [link to relevant documentation]. Figure 7 The figure is a schematic diagram of a flywheel dynamic determination device for half-order vibration of an engine provided in an embodiment of this application. Figure 7 As shown, the device may include:

[0076] The position selection unit 201 is used to select at least three positions on the flywheel housing of the engine, each position being provided with a displacement sensor facing the flywheel;

[0077] The displacement signal acquisition unit 202 is used to acquire the displacement signal of each displacement sensor, wherein the displacement signal is a displacement signal representing the change in the vertical distance between each sensor and the flywheel of the engine;

[0078] The disturbance signal calculation unit 203 is used to calculate the disturbance signal of the flywheel based on the displacement signal and the coordinate value of the displacement sensor on the flywheel housing plane;

[0079] The half-order vibration determination unit 204 is used to determine the frequency and time of the occurrence of the half-order vibration;

[0080] The flywheel dynamic determination unit 205 is used to determine the flywheel dynamics when the engine experiences a half-order vibration based on the disturbance signal and the frequency and time of the half-order vibration.

[0081] It should be noted that the implementation of each unit in this embodiment can be found in the above method embodiment, and will not be repeated here.

[0082] In addition, this application embodiment also provides a device, the device including: a processor and a memory; the memory is used to store instructions; the processor is used to execute the instructions in the memory to execute the method for determining the half-order vibration of the engine.

[0083] This application also provides a computer-readable storage medium storing program code or instructions that, when run on a computer, cause the computer to execute the method for determining the half-order vibration of an engine described above.

[0084] As can be seen, this embodiment of the application arranges displacement sensors at at least three locations on the flywheel housing, collects displacement signals of the vertical distance between each displacement sensor and the flywheel, determines the displacement signals of three points on the flywheel plane, and calculates the disturbance signal of the entire flywheel plane based on the displacement signals and the coordinate values ​​of the displacement sensors. Then, by obtaining the frequency and time when the half-order vibration actually occurs, the flywheel dynamics when the half-order vibration occurs are determined, realizing the testing of the flywheel dynamics when the engine experiences half-order vibration, and providing a more accurate analysis of the cause of the engine's half-order vibration.

[0085] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems or apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.

[0086] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0087] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0088] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0089] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for determining the flywheel dynamics of a half-order vibration of an engine, characterized in that, The method includes: At least three locations are selected on the flywheel housing of the engine, and a displacement sensor facing the flywheel is arranged at each of the locations; The displacement signal of each displacement sensor is acquired, and the displacement signal is a displacement signal representing the change in the vertical distance between each displacement sensor and the flywheel of the engine; Based on the displacement signal and the coordinate values ​​of the displacement sensor on the flywheel housing plane, the disturbance signal of the flywheel is calculated: the disturbance signal of the flywheel includes the following disturbance signal along the X direction. Disturbance signal around the Y direction and the disturbance signal around the Z direction ; ； ； ； Wherein, the origin of the coordinate system is the intersection of the flywheel and the crankshaft; S A S B S C Displacement signal for each of the displacement sensors; Y A Y B Y C Z A Z B Z C The coordinate values ​​of each displacement sensor on the flywheel housing plane; Determine the frequency and timing of the half-order oscillation; Based on the disturbance signal and the frequency and time of the half-order vibration, the flywheel dynamics when the engine experiences half-order vibration are determined.

2. The method according to claim 1, characterized in that, The method further includes: Obtain the cylinder pressure signal of the engine; Based on the cylinder pressure signal and the frequency and time of the half-order vibration, the working condition of each cylinder when the engine experiences half-order vibration is determined.

3. The method according to claim 1, wherein determining the frequency and time of the occurrence of the half-order vibration comprises: The frequency and timing of the half-order vibration are determined based on the engine's noise and vibration signals.

4. The method according to claim 3, wherein the noise signal of the engine is obtained from a microphone located outside the exhaust side of the engine.

5. The method according to claim 3, wherein the vibration signal of the engine is obtained based on an acceleration sensor, the acceleration sensor being located on the outer surface of the engine block outside the cylinder wall and at the same height as the crankshaft.

6. The method according to claim 3, wherein determining the frequency and time of the half-order vibration based on the engine's noise signal and vibration signal comprises: Wavelet analysis is performed on the noise and vibration signals of the engine. Based on the results of the wavelet analysis, the frequency and time of the half-order vibration are identified.

7. The method according to claim 2, wherein the cylinder pressure signal of the engine is obtained from a cylinder pressure sensor located in each cylinder of the engine.

8. A device for determining half-order vibration of an engine, characterized in that, The device includes: A position selection unit is used to select at least three positions on the flywheel housing of the engine, each of which is provided with a displacement sensor facing the flywheel; A displacement signal acquisition unit is used to acquire the displacement signal of each displacement sensor, wherein the displacement signal is a displacement signal representing the change in the vertical distance between each sensor and the flywheel of the engine; The disturbance signal calculation unit is used to calculate the disturbance signal of the flywheel based on the displacement signal and the coordinate values ​​of the displacement sensor on the flywheel housing plane; the disturbance signal of the flywheel includes the following disturbance signals along the X direction. Disturbance signal around the Y direction and the disturbance signal around the Z direction ; ； ； ； Wherein, the origin of the coordinate system is the intersection of the flywheel and the crankshaft; S A S B S C Displacement signal for each of the displacement sensors; Y A Y B Y C Z A Z B Z C The coordinate values ​​of each displacement sensor on the flywheel housing plane; The half-order vibration determination unit is used to determine the frequency and time of the occurrence of half-order vibration. The flywheel dynamic determination unit is used to determine the flywheel dynamics when the engine experiences a half-order vibration, based on the disturbance signal and the frequency and time of the half-order vibration.

9. A device, characterized in that, The device includes: a processor and a memory; The memory is used to store instructions; The processor is configured to execute the instructions in the memory to perform the method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores program code or instructions that, when executed on a computer, cause the computer to perform the method described in any one of claims 1-7.

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