Multi-cylinder engine same-frequency out-phase pulse simulation test system

Abstract

The invention provides a multi-cylinder engine same-frequency out-phase pulse simulation test system. The multi-cylinder engine same-frequency out-phase pulse simulation test system comprises a turbocharger to be tested, an exhaust manifold, a single-source pulse generator and an air inlet pipe. An air inlet of the single-source pulse generator is connected with an external air source through an air inlet pipe, the single-source pulse generator is provided with a plurality of air outlets, and the plurality of air outlets are connected with an air inlet of a turbocharger to be tested through an exhaust manifold; the single-source pulse generator is connected to the driving adjusting device, the driving adjusting device drives the single-source pulse generator to output same-frequency out-phase pulse airflow, and the single-source pulse generator is used for simulating the air inlet condition of an engine exhaust manifold in the exhaust state of the engine so as to simulate the operation state of the turbocharger to be tested on a rack in the exhaust state of the engine. The multi-cylinder engine same-frequency out-of-phase pulse simulation test system simulates the real mixing state of multi-strand out-of-phase pulse exhaust at the downstream of the exhaust port of the engine, so that rack simulation of the same-frequency out-of-phase pulse exhaust state of the engine is realized.

Description

Technical Field

[0001] The present application belongs to the technical field of engine simulation test, and in particular, relates to a same-frequency and different-phase pulse simulation test system for a multi-cylinder engine. Background Art

[0002] In the field of internal combustion engine research and development, exhaust gas turbocharging is a common technology used to improve the specific power and fuel economy of internal combustion engines and reduce exhaust gas and noise pollution. In a turbocharger, the main task of the turbine is to convert exhaust gas energy into mechanical energy and perform external work, and the turbine rotor is one of the main components that perform this conversion process.

[0003] In actual engineering, the turbocharger turbine is generally driven by the engine exhaust gas, and its inlet boundary condition is a complex unsteady fluid formed by the mixture of multi-cylinder diesel engine pulse exhaust with the same frequency and different phases. However, due to the high cost of engine purchase and the long development cycle, providing the turbocharger turbine with a real diesel engine multi-cylinder pulse exhaust with the same frequency and different phases will greatly increase the time and economic cost of the test, and the use of stable flow or single pulse flow to simulate and replace the actual working conditions cannot meet the requirements of the research and development process for the accuracy of bench test results. Summary of the invention

[0004] In view of this, the present application aims to propose a multi-cylinder engine same-frequency and different-phase pulse simulation test system to solve the problem that the accuracy requirements of bench test results cannot be met during the research and development process.

[0005] To achieve the above purpose, the technical solution of this application is implemented as follows:

[0006] The present application provides a multi-cylinder engine same-frequency and different-phase pulse simulation test system, comprising a turbocharger to be tested, an exhaust manifold, a single-source pulse generator and an intake pipe;

[0007] The air inlet of the single-source pulse generator is connected to an external air source through the air inlet pipe, and the single-source pulse generator is provided with a plurality of air outlets, and the plurality of air outlets are connected to the air inlet of the turbocharger to be tested through the exhaust manifold;

[0008] The single-source pulse generator is connected to a driving and adjusting device, and is driven by the driving and adjusting device to output pulse airflows of the same frequency and different phases. The single-source pulse generator is used to simulate the intake condition of the engine exhaust manifold under the engine exhaust state, so as to simulate the bench operation state of the turbocharger to be tested under the engine exhaust.

[0009] Furthermore, the single-source pulse generator includes a generator body, a hollow cavity is provided in the generator body, an air inlet is provided on one side of the generator body, and a plurality of air outlets are provided on the other side, the valve plug is arranged in the hollow cavity through a valve shaft, the valve shaft is connected to the drive and adjustment device, and the drive and adjustment device drives the valve shaft to drive the valve plug to perform periodic reciprocating motion, thereby controlling the connectivity state of the air path between the air inlet and the plurality of air outlets.

[0010] Furthermore, a through shaft hole is provided on the outer wall of the generator body, and the valve shaft is arranged in the shaft hole through a sealing and lubricating structure;

[0011] The valve plug is assembled onto the valve shaft, and the air outlet is blocked by the valve plug to form a ventilation / blocking area.

[0012] Furthermore, the plurality of air outlets are arranged vertically and spaced apart;

[0013] The valve plug has a stepped structure and is arranged corresponding to the plurality of gas outlets to cooperate to form an exhaust channel with a plurality of fixed pulse phase differences.

[0014] Furthermore, the inner wall of the air outlet side of the cavity body and the valve plug are sealed by a labyrinth sealing structure.

[0015] Furthermore, one end or both ends of the valve shaft are connected to a power source via an intermediate linkage structure to control the action of the power source and drive the valve shaft to reciprocate via the intermediate linkage mechanism.

[0016] Furthermore, the intermediate linkage mechanism includes a cam mechanism or a crank-connecting rod mechanism.

[0017] Furthermore, the power source is a drive motor.

[0018] Compared with the prior art, the multi-cylinder engine same-frequency and different-phase pulse simulation test system described in this application has the following beneficial effects:

[0019] The present application describes a multi-cylinder engine same-frequency and different-phase pulse simulation test system, which achieves the goal of fluidizing a stable gas source into multiple same-frequency and different-phase pulse gases by introducing a low-cost single-source pulse generator into the test system, and then simulates the real exhaust state of the engine by controlling the mixing of multiple exhaust gases in the engine exhaust manifold, providing the turbocharger with an intake condition that is closer to the actual working condition, thereby achieving low-cost simulation of the complex pulse intake condition of the turbocharger. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0021] Figure 1 A schematic diagram of a multi-cylinder engine same-frequency and different-phase pulse simulation test system according to an embodiment of the present application;

[0022] Figure 2 This is a schematic diagram of the structure of the single-source pulse generator described in an embodiment of the present application.

[0023] Description of reference numerals:

[0024] 1- generator body; 11- air inlet; 12- air outlet; 2- valve plug; 3- valve shaft. DETAILED DESCRIPTION

[0025] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0026] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should be the usual meanings understood by people with ordinary skills in the field to which the present application belongs. The "first", "second" and similar words used in the embodiments of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing in front of the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0027] See also Figure 1 As shown, this embodiment provides a multi-cylinder engine same-frequency and different-phase pulse simulation test system, including a turbocharger to be tested, an exhaust manifold, a single-source pulse generator and an intake pipe;

[0028] The air inlet 11 of the single-source pulse generator is connected to an external air source through an air inlet pipe, and the single-source pulse generator is provided with a plurality of air outlets 12, and the plurality of air outlets 12 are connected to the air inlet 11 of the turbocharger to be tested through an exhaust manifold;

[0029] The single-source pulse generator is connected to the driving and regulating device, which drives the single-source pulse generator to output pulse airflows of the same frequency and different phases. The single-source pulse generator is used to simulate the intake condition of the engine exhaust manifold under the engine exhaust state, so as to simulate the operating state of the turbocharger to be tested under the engine exhaust.

[0030] Specifically, in this embodiment, the simulation test system includes an air source, a single-source pulse generator, an engine manifold, a turbocharger and other tested components, and related connecting pipelines. Compared with the conventional turbocharger test system, the simulation test system adds a single-source pulse generator and an engine manifold between the air source and the turbocharger and other tested components, and uses the single-source pulse generator to differentiate the stable air source flow into multiple branch exhausts with a fixed pulse phase difference to simulate the multi-cylinder exhaust state of the engine, and uses the engine manifold to converge multiple branch exhausts with a fixed pulse phase difference into one, simulating the real mixing state of multiple out-of-phase pulse exhausts downstream of the engine exhaust port, thereby realizing the bench simulation of the same-frequency out-of-phase pulse exhaust state of the engine.

[0031] By introducing a low-cost single-source pulse generator into the test system, the goal of converting the stable gas source into multiple pulse airflows of the same frequency and different phases is achieved. Then, by controlling the mixing of multiple exhaust gases in the engine exhaust manifold, the simulation of the real exhaust state of the engine is achieved, providing the turbocharger with an intake condition that is closer to the actual working condition, and realizing low-cost simulation of the complex pulse intake condition of the turbocharger.

[0032] In some embodiments, the single-source pulse generator includes a generator body 1, a cavity is provided in the generator body 1, an air inlet 11 is provided on one side of the generator body 1, and a plurality of air outlets 12 are provided on the other side, a valve plug 2 is arranged in the cavity through a valve shaft 3, and the valve shaft 3 is connected to a driving and adjusting device, and the driving and adjusting device drives the valve shaft 3 to drive the valve plug 2 to perform periodic reciprocating motion, thereby controlling the connection state of the air path between the air inlet 11 and the plurality of air outlets 12;

[0033] A penetrating axial hole is opened on the outer wall of the generator body 1, and the valve shaft 3 is arranged in the axial hole through a sealing and lubricating structure. The valve plug 2 is assembled on the valve shaft 3, and the air outlet 12 is blocked by the valve plug 2 to form a ventilation / air blocking area.

[0034] Specifically, in this embodiment, according to the actual exhaust pulse phase difference of each cylinder of the engine, a single-source pulse generator with the ability to generate multiple fixed pulse phase difference exhaust is designed. Specifically, the single-source pulse generator includes a pulse generator body 1, a valve plug 2, a valve shaft 3 and an externally connected driving and adjusting device, wherein an air inlet 11 (such as Figure 2 Outer top), outlet 12 (such as Figure 2Outer lower side) and shaft through hole (such as Figure 2 On the left and right sides), a sealing and lubricating mechanism is arranged between the pulse generator shaft hole and the reciprocating shaft of the pulse generator valve plug 2. The sealing and lubricating mechanism adopted in this embodiment can be a sealing structure commonly found in existing engines such as a sealing sleeve, which can achieve the sealing between the valve shaft 3 and the pulse generator body, and no further details will be given here.

[0035] In this embodiment, there are one or more ventilation / blocking areas. During operation, ventilation / blocking is allowed to pass through multiple air outlets 12 in sequence, so that the pressures of the multiple air outlets 12 fluctuate with the same frequency and in different phases, forming multiple pulse airflows with the same frequency and in different phases.

[0036] During the test, the air source intake pressure and the operating speed of the single-source pulse generator were adjusted according to the actual working conditions of the engine. The connection state of the air path between the two lower air outlets 12 and the air inlet 11 was controlled by the periodic reciprocating motion of the valve plug 2, so as to achieve fine control of the exhaust pressure pulse amplitude and frequency, thereby achieving the goal of forming pulse pressure waves of the same frequency and out of phase at the two air outlets 12.

[0037] In some embodiments, the plurality of air outlets 12 are arranged in an up-and-down manner;

[0038] The valve plug 2 has a stepped structure and is arranged corresponding to the plurality of gas outlets 12 to cooperate to form an exhaust passage with a plurality of fixed pulse phase differences.

[0039] Specifically, in this embodiment, for a two-cylinder engine, the valve plug 2 can be set to a Z-shaped structure, and the middle part of the valve plug 2 is arranged perpendicular to the upper and lower transverse parts. The Z-shaped valve plug 2 consists of a middle part and two transverse parts, and the two transverse parts correspond to the two set air outlets. This design allows the valve plug 2 to open and close different air outlets 12 at different phases when moving to form an exhaust channel with two fixed pulse phase differences.

[0040] The valve plug 2 is driven by the valve shaft 3 to make reciprocating motion in the cylinder body. Due to the Z-shaped structure, the lateral parts (upper lateral part and lower lateral part) of the valve plug 2 will have a phase difference during the movement, that is, when one lateral part starts to open, the other lateral part may still be in a closed state, or has been closed and is ready to open.

[0041] Although the transverse parts of the valve plug 2 have phase differences in movement, their opening and closing actions are synchronized, that is, they all move periodically at the same frequency. Due to the characteristics of the Z-shaped structure, the upper and lower transverse parts will not open at the same time during the movement, thus forming a difference. When one transverse part is opened, the other transverse part is closed, and vice versa. When one transverse part of the valve plug 2 is opened, the gas will be quickly discharged from the corresponding gas outlet 12, forming a pulse airflow. With the reciprocating motion of the valve plug 2, the generation and stop of this pulse airflow are periodically alternated.

[0042] The specific working steps are as follows:

[0043] The valve plug 2 is opened: the middle part and the first transverse part of the valve plug 2 begin to move to the left, opening the corresponding gas outlet 12, and the gas flows out.

[0044] Phase conversion: When the middle portion and the first lateral portion of the valve plug 2 approach the side wall of the generator body 1 , the second lateral portion starts to move to the right, closes the first air outlet 12 , and prepares to open the second air outlet 12 .

[0045] Gas path switching: the first transverse portion starts to move to the right, closing the first gas outlet 12 , while the second transverse portion opens the second gas outlet 12 .

[0046] Repeat cycle: The above steps are repeated, but due to the phase difference, the opening and closing of the airflow do not occur at the same time, thus forming a pulsed airflow with the same frequency and different phases.

[0047] Based on the same working principle as that of a two-cylinder engine, for a four-cylinder engine, the valve plug 2 can be set to a W-shaped structure with a stepped layout, and the formed stepped structure corresponds to the four set air outlets. Then, the valve plug 2 is driven to move by the valve shaft, allowing the valve plug 2 to open and close different air outlets 12 at different phases during movement, so as to form an exhaust channel with four fixed pulse phase differences.

[0048] It should be noted that the present application is only explained using a two-cylinder engine as an example, and the present application is also applicable to a three-cylinder engine and a four-cylinder engine. For a specific type of engine, the number of air outlets and the structural setting of the valve plug can be flexibly arranged according to actual conditions. Here, only a design idea is provided, and the specific structural setting will not be elaborated on.

[0049] In some embodiments, the inner wall of the cavity body on the side of the gas outlet 12 and the valve plug 2 are sealed by a labyrinth-type sealing structure.

[0050] Specifically, in this embodiment, matching sealing teeth are provided on the inner wall on the side of the air outlet 12 of the cavity body and on the valve plug 2. Through the shape and arrangement of the sealing tooth structure, the gas is forced to change direction when passing through the gap, thereby increasing the flow resistance. The gas in the cavity needs to pass through the narrow gap multiple times, and each throttling further reduces the gas flow rate, thereby reducing leakage. In addition, due to the multiple throttling effects of the maze-type structure on the airflow, the noise generated by the gas flow can be reduced, thereby reducing the noise level of the engine.

[0051] In some embodiments, one end or both ends of the valve shaft 3 are connected to a power source (the power source used in this embodiment is a drive motor) through an intermediate linkage structure (the intermediate linkage mechanism used in this embodiment includes a cam mechanism or a crank-connecting rod mechanism) to control the action of the power source and drive the valve shaft 3 to reciprocate through the intermediate linkage mechanism.

[0052] Specifically, in this embodiment, one end or both ends of the valve shaft 3 are connected to the intermediate linkage mechanism through a mechanical connection (such as a pin shaft, a key connection, etc.). The intermediate linkage mechanism described in this embodiment is explained using a cam mechanism or a crank-connecting rod mechanism as an example, and other linkage methods can also be used to implement it, which is not further limited here.

[0053] For the cam mechanism: the cam pushes the follower (such as the valve shaft 3) through its contour to achieve reciprocating motion; for the crank-connecting rod mechanism: the rotational motion of the crank is converted into the reciprocating linear motion of the valve shaft 3 through the connecting rod, and the action of the power source (such as a motor) is converted into the motion of the valve shaft 3 through the intermediate linkage mechanism.

[0054] The intermediate linkage mechanism can accurately control the motion trajectory and speed of the valve shaft 3, ensure accurate control of the valve during opening and closing, and convert the power source of the rotary motion into the linear reciprocating motion of the valve shaft 3, which is suitable for valve control requirements.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention.

[0056] The embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the scope of protection of the present application.

Claims

1. A multi-cylinder engine same-frequency and different-phase pulse simulation test system, characterized by: Includes the turbocharger to be tested, exhaust manifold, single source pulse generator and intake pipe; The air inlet of the single-source pulse generator is connected to an external air source through the air inlet pipe, and the single-source pulse generator is provided with a plurality of air outlets, and the plurality of air outlets are connected to the air inlet of the turbocharger to be tested through the exhaust manifold; The single-source pulse generator is connected to a driving and adjusting device, and is driven by the driving and adjusting device to output pulse airflows of the same frequency and different phases. The single-source pulse generator is used to simulate the intake condition of the engine exhaust manifold under the engine exhaust state, so as to simulate the bench operation state of the turbocharger to be tested under the engine exhaust.

2. A multi-cylinder engine same-frequency and different-phase pulse simulation test system according to claim 1, characterized in that: The single-source pulse generator includes a generator body, a cavity is provided in the generator body, an air inlet is provided on one side of the generator body, and a plurality of air outlets are provided on the other side. The valve plug is arranged in the cavity through a valve shaft, and the valve shaft is connected to the driving and adjusting device. The driving and adjusting device drives the valve shaft to drive the valve plug to perform periodic reciprocating motion, thereby controlling the connectivity state of the air path between the air inlet and the plurality of air outlets.

3. A multi-cylinder engine same-frequency and different-phase pulse simulation test system according to claim 2, characterized in that: A through shaft hole is provided on the outer wall of the generator body, and the valve shaft is arranged in the shaft hole through a sealing and lubricating structure; The valve plug is assembled onto the valve shaft, and the air outlet is blocked by the valve plug to form a ventilation / blocking area.

4. A multi-cylinder engine same-frequency and different-phase pulse simulation test system according to claim 3, characterized in that: The plurality of air outlets are arranged vertically and spaced apart; The valve plug has a stepped structure and is arranged corresponding to the plurality of gas outlets to cooperate to form an exhaust channel with a plurality of fixed pulse phase differences.

5. A multi-cylinder engine same frequency and different phase pulse simulation test system according to claim 2, characterized in that: The inner wall of the cavity body at the gas outlet side and the valve plug are sealed by a labyrinth sealing structure.

6. A multi-cylinder engine same-frequency and different-phase pulse simulation test system according to claim 1, characterized in that: One end or both ends of the valve shaft are connected to a power source through an intermediate linkage structure to control the action of the power source and drive the valve shaft to reciprocate through the intermediate linkage mechanism.

7. A multi-cylinder engine same frequency and different phase pulse simulation test system according to claim 6, characterized in that: The intermediate linkage mechanism includes a cam mechanism or a crank-connecting rod mechanism.

8. A multi-cylinder engine same frequency and different phase pulse simulation test system according to claim 6, characterized in that: The power source is a driving motor.

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