Engine intake and exhaust pressure simulation method and system

Abstract

The invention relates to an engine intake and exhaust pressure simulation method and system, and belongs to the technical field of engine intake and exhaust pressure simulation. The engine intake and exhaust pressure simulation method comprises the steps of determining the working rotating speed of a negative pressure pump under simulated intake and exhaust pressure based on the engine simulated intake and exhaust pressure and the mapping relation between the working rotating speed of the negative pressure pump and an altitude interval; according to the working rotating speed of the negative pressure pump, the negative pressure pump is driven to work so as to extract air from the surge tank; according to the working rotating speed of the air supply pump, the air supply pump is driven to work so as to supply air to the surge tank; and based on the actual air pressure in the surge tank and the simulated intake and exhaust pressure, driving the air supplementing pump to work so as to adjust the surge tank to the simulated intake and exhaust pressure. The engine intake and exhaust simulation experiment for simulating plateau characteristics can be completed in a non-plateau area, the experiment operation is convenient, the experiment precision is easy to control, and the cost is low.

Description

Technical Field

[0001] The present application relates to the technical field of engine intake and exhaust pressure simulation, and in particular to an engine intake and exhaust pressure simulation method and system. Background Art

[0002] Plateau areas are at a high altitude, and atmospheric pressure, air density, and oxygen content all decrease with increasing altitude. These changes have a significant impact on the engine's intake and exhaust system, fuel spray, combustion process, and emission characteristics. Therefore, simulating the engine intake and exhaust pressure in plateau environments is of great significance for studying the engine's performance and optimizing its design in plateau areas.

[0003] Traditional plateau performance tests on engines involve installing an engine bench in a plateau area, or installing the engine on a vehicle and driving the vehicle to a plateau area for plateau testing. To conduct tests at different altitudes, the bench or vehicle needs to be placed in areas with different altitudes, which is a complex process and has high testing costs. Summary of the invention

[0004] The embodiments of the present application provide an engine intake and exhaust pressure simulation method and system to solve the defect in the related art that conducting tests at different altitudes requires placing a test bench or a whole vehicle at different altitudes, which is a complicated process and has high test costs.

[0005] First aspect:

[0006] An embodiment of the present application provides a method for simulating the intake and exhaust pressures of an engine, comprising: determining the operating speed of the negative pressure pump under the simulated intake and exhaust pressures of the engine and a mapping relationship between the operating speed of the negative pressure pump and the altitude range; driving the negative pressure pump to operate according to the operating speed of the negative pressure pump to draw air into a pressure-stabilizing tank; driving the air supply pump to operate according to the operating speed of the air supply pump to supply air to the pressure-stabilizing tank; and driving the air make-up pump to operate based on the actual air pressure in the pressure-stabilizing tank and the simulated intake and exhaust pressures to adjust the pressure-stabilizing tank to the simulated intake and exhaust pressures.

[0007] This application is based on the simulated intake and exhaust pressures of the engine, and the mapping relationship between the working speed of the negative pressure pump and the altitude range. Therefore, the specific environment of this application is based on the characteristics of the plateau, simulating the engine intake and exhaust conditions under the plateau environment, which is helpful to study the performance of the engine under special climatic conditions of the plateau, such as low pressure, low temperature, and low humidity.

[0008] In some embodiments, the method also includes obtaining a mapping relationship between the working speed of the negative pressure pump and the altitude interval, specifically including: dividing the altitude to obtain multiple altitude intervals; using the atmospheric pressure corresponding to the upper limit of the altitude in the altitude interval as the calibration pressure of the altitude interval; controlling the operation of the negative pressure pump to obtain the speed when the calibration pressure is reached, and using the speed as the working speed of the negative pressure pump; based on the calibration pressure of each altitude interval and the working speed of the negative pressure pump, obtaining a mapping relationship between the working speed of the negative pressure pump and the altitude interval.

[0009] In some embodiments, based on the intake and exhaust pressures simulated by the engine and the mapping relationship between the operating speed of the negative pressure pump and the altitude interval, the operating speed of the negative pressure pump under the simulated intake and exhaust pressure is determined, specifically including: comparing the simulated intake and exhaust pressures with the atmospheric pressure intervals corresponding to each altitude interval; finding the altitude interval corresponding to the atmospheric pressure interval where the simulated intake and exhaust pressure is located; based on the mapping relationship between the found altitude interval and the operating speed of the negative pressure pump and the altitude interval, the operating speed of the negative pressure pump under the simulated intake and exhaust pressure is determined.

[0010] In some embodiments, starting from an altitude of 0 m, the altitude is divided into intervals of 1000 m.

[0011] In some embodiments, the method also includes obtaining the operating speed of the air supply pump, and obtaining the operating speed of the air supply pump specifically includes: obtaining the air supply of the air supply pump based on the maximum air consumption of the engine and the air consumption adjustment coefficient; controlling the operation of the air supply pump to obtain the speed when the air supply reaches the said air supply, and using the speed as the operating speed of the air supply pump.

[0012] In some embodiments, the gas consumption adjustment coefficient has a value range greater than 1.5.

[0013] In some embodiments, the air supply volume of the air supply pump is the product of the maximum air consumption of the engine and the air consumption adjustment coefficient.

[0014] In some embodiments, a pressure sensor is provided on the pressure stabilizing tank.

[0015] Second aspect:

[0016] An embodiment of the present application provides an engine intake and exhaust simulation system, which is characterized by comprising a pressure stabilizing tank, and an air supplement pump, an air supply pump, a negative pressure pump, and a pressure sensor connected to the pressure stabilizing tank.

[0017] In some embodiments, a controller is also included, which is connected to the air supplement pump, the air supply pump, the negative pressure pump, and the pressure sensor, and is used to: determine the operating speed of the negative pressure pump under the simulated intake and exhaust pressures based on the intake and exhaust pressures simulated by the engine and the mapping relationship between the operating speed of the negative pressure pump and the altitude range; drive the negative pressure pump to work according to the operating speed of the negative pressure pump to draw air into the pressure stabilizing tank; drive the air supply pump to work according to the operating speed of the air supply pump to supply air to the pressure stabilizing tank; drive the air supplement pump to work based on the actual air pressure in the pressure stabilizing tank and the simulated intake and exhaust pressures to adjust the pressure stabilizing tank to the simulated intake and exhaust pressures.

[0018] The beneficial effects of the technical solution provided by this application include:

[0019] An embodiment of the present application provides an engine intake and exhaust pressure simulation method and system, wherein an engine intake and exhaust pressure simulation method includes the following steps: based on the intake and exhaust pressure simulated by the engine and the mapping relationship between the operating speed of the negative pressure pump and the altitude range, determine the operating speed of the negative pressure pump under the simulated intake and exhaust pressure; according to the operating speed of the negative pressure pump, drive the negative pressure pump to work to draw air into the pressure stabilizing tank; according to the operating speed of the air supply pump, drive the air supply pump to work to supply air to the pressure stabilizing tank; based on the actual air pressure in the pressure stabilizing tank and the simulated intake and exhaust pressure, drive the air supply pump to work to adjust the pressure stabilizing tank to the simulated intake and exhaust pressure.

[0020] Therefore, based on the cavity of the pressure-sustaining tank as a fixed container, a stable air pressure can be directly provided to the engine. The air supply pump is used as an active pump to provide a fixed flow of air pressure to the pressure-sustaining tank. The negative pressure pump draws air from the pressure-sustaining tank, and finally, the air supply pump injects air into the pressure-sustaining tank to stabilize the air pressure in the pressure-sustaining tank. Therefore, during the intake and exhaust pressure experiment simulated by the engine, the negative pressure pump is driven to work according to the working speed of the negative pressure pump to draw air from the pressure-sustaining tank, and the air supply pump is driven to work according to the working speed of the air supply pump to supply air to the pressure-sustaining tank. Finally, based on the actual air pressure in the pressure-sustaining tank and the simulated intake and exhaust pressure, the air supply pump is driven to work, so that the air pressure environment in the pressure-sustaining tank meets the experimental requirements, and the air supply pump and the negative pressure pump operate stably. When conducting tests at different altitudes, there is no need to conduct them in a plateau environment. The experiment can be simulated by the pressure-sustaining tank, the air supply pump, the negative pressure pump, and the air supply pump, which is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 A schematic diagram of an engine intake and exhaust pressure simulation method and system provided in an embodiment of the present application;

[0023] Reference numerals:

[0024] 1. Engine; 2. Negative pressure pump; 3. Pressure regulating tank; 4. Air supply pump; 5. Air supplement pump; 6. Controller; 70. Intake pipe; 71. Exhaust pipe. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0026] The embodiments of the present application provide an engine intake and exhaust pressure simulation method and system, which can solve the problem that conducting tests at different altitudes requires placing a test bench or a whole vehicle at different altitudes, which is a complicated process and has high test costs.

[0027] Example 1

[0028] See also Figure 1 As shown, an embodiment of the present application provides a method for simulating the intake and exhaust pressure of an engine, including: determining the operating speed of the negative pressure pump 2 under the simulated intake and exhaust pressure based on the intake and exhaust pressure simulated by the engine 1, and the mapping relationship between the operating speed of the negative pressure pump 2 and the altitude range; driving the negative pressure pump 2 to work according to the operating speed of the negative pressure pump 2 to draw air into the pressure-stabilizing tank 3; driving the air supply pump 4 to work according to the operating speed of the air supply pump 4 to supply air to the pressure-stabilizing tank 3; and driving the air make-up pump 5 to work based on the actual air pressure in the pressure-stabilizing tank 3 and the simulated intake and exhaust pressure to adjust the pressure-stabilizing tank 3 to the simulated intake and exhaust pressure.

[0029] In the present application, the engine intake and exhaust pressure simulation method is based on a simulation experiment based on the characteristic environment of the plateau. The economic development of the plateau area has led to a gradual increase in motor vehicles and construction machinery. Simulating the intake and exhaust conditions of the engine 1 under the plateau environment is helpful to study the performance of the engine 1 under the special climatic conditions of the plateau such as low pressure, low temperature, and low humidity. It puts forward higher requirements on the adaptability of the engine 1 to ensure its stable operation under extreme conditions.

[0030] Therefore, when the present application is used, first, according to the mapping relationship between the simulated intake and exhaust pressure of the engine 1 and the altitude interval, the operating speed that the negative pressure pump 2 needs to reach at a specific altitude is calculated. This is because as the altitude increases, the atmospheric pressure gradually decreases, and the intake and exhaust pressure of the engine 1 will also change accordingly, so the working state of the negative pressure pump 2 needs to be adjusted accordingly. The way to confirm the operating speed of the negative pressure pump 2 includes but is not limited to, according to the simulated intake and exhaust pressure and altitude, through a preset algorithm or lookup table.

[0031] During the experiment, the main function of the negative pressure pump 2 is to pump air into the pressure stabilizing tank 3 to reduce the air pressure in the pressure stabilizing tank 3; the function of the air supply pump 4 is to supply air into the pressure stabilizing tank 3 to increase the air pressure in the pressure stabilizing tank 3, and the working speed of the air supply pump 4 also needs to be determined according to the preset algorithm or conditions; the function of the air supply pump 5 is to adjust the air pressure in the pressure stabilizing tank 3 to make it closer to the simulated intake and exhaust pressure; and based on the difference between the actual air pressure in the pressure stabilizing tank 3 and the simulated intake and exhaust pressure in the pressure stabilizing tank 3, the working state of the air supply pump 5 is adjusted. If the actual air pressure is lower than the simulated air pressure, the air supply pump 5 can add gas to the pressure stabilizing tank 3. Then, by accurately controlling the working speed and state of the negative pressure pump 2, the air supply pump 4 and the air supply pump 5, the intake and exhaust pressure environment of the engine 1 at different altitudes can be simulated, providing important support for the research and development, testing and optimization of the engine 1. Real-time adjustment of the working state of the air supply pump 5 can ensure that the air pressure in the pressure-stabilizing tank 3 is always maintained near the simulated intake and exhaust pressures, thereby improving the accuracy and reliability of the simulation. Optimization of the working state of each pump can reduce energy consumption and improve the operating efficiency of the entire system.

[0032] In the present application, in order to detect the pressure of the pressure-stabilizing tank 3, a pressure sensor is provided on the pressure-stabilizing tank 3. The pressure sensor monitors the pressure inside the pressure-stabilizing tank 3 in real time. Therefore, according to the actual pressure inside the pressure-stabilizing tank 3, the air supply pump 5 can be timely adjusted to supplement the pressure inside the pressure-stabilizing tank 3.

[0033] In the present application, the method for simulating the intake and exhaust pressures of the engine 1 also includes obtaining a mapping relationship between the working speed of the negative pressure pump 2 and the altitude interval, specifically including: dividing the altitude to obtain multiple altitude intervals; using the atmospheric pressure corresponding to the upper limit of the altitude in the altitude interval as the calibrated pressure of the altitude interval, and the calibrated pressure represents the approximate range of the atmospheric pressure within the altitude interval; then controlling the operation of the negative pressure pump 2 to obtain the speed of the negative pressure pump 2 when the calibrated pressure is reached, and using the speed as the working speed of the negative pressure pump 2, mainly confirming the working speed of the negative pressure pump 2 in the corresponding altitude interval through a preset algorithm or a lookup table; based on the calibrated pressure of each altitude interval and the working speed of the negative pressure pump 2, obtaining a mapping relationship between the working speed of the negative pressure pump 2 and the altitude interval, the mapping relationship can be in a tabular form or a functional relationship.

[0034] By establishing a mapping relationship between the operating speed of the negative pressure pump 2 and the altitude range, the intake and exhaust pressure environment of the engine 1 at different altitudes can be accurately simulated, which is of great significance for studying the performance of the engine 1 in a plateau environment. With this mapping relationship, the working state of the negative pressure pump 2 can be adjusted more accurately, thereby avoiding unnecessary energy consumption and wear, and helping to improve the operating efficiency of the entire simulation system.

[0035] In the present application, based on the intake and exhaust pressures simulated by the engine 1 and the mapping relationship between the operating speed of the negative pressure pump 2 and the altitude interval, the operating speed of the negative pressure pump 2 under the simulated intake and exhaust pressure is determined, specifically including: comparing the simulated intake and exhaust pressures with the atmospheric pressure intervals corresponding to each altitude interval; finding the altitude interval corresponding to the atmospheric pressure interval in which the simulated intake and exhaust pressure is located; based on the mapping relationship between the altitude interval found and the operating speed of the negative pressure pump 2 with respect to the altitude interval, the operating speed of the negative pressure pump 2 under the simulated intake and exhaust pressure is determined.

[0036] During the operation of the engine 1, the intake and exhaust pressures are important parameters that reflect the working state of the engine 1. The intake pressure usually refers to the pressure of the air inhaled by the engine 1, while the exhaust pressure refers to the pressure when the engine 1 discharges the exhaust gas. Because the atmospheric pressure gradually decreases with the increase of the altitude, different altitude intervals correspond to different atmospheric pressure intervals. In this application, starting from 0m altitude, the altitude is divided into intervals of 1000m.

[0037] The simulated intake and exhaust pressure is compared with the atmospheric pressure interval corresponding to each altitude interval. For example, if the simulated air pressure is -30Kpa, then the altitude interval corresponding to -30Kpa is found, and then the atmospheric pressure corresponding to the upper limit value in this altitude interval is used as the calibration pressure of the altitude interval. Under the calibration pressure condition, the working speed of the negative pressure pump 2 is confirmed according to the preset algorithm or the lookup table. At this time, based on the difference between the actual pressure in the pressure stabilizing tank 3 and the simulated pressure, the air supply in the pressure stabilizing tank 3 is further supplied by the air supply pump 5 to stabilize the air pressure in the pressure stabilizing tank 3 to meet the simulated altitude intake and exhaust pressure demand range. The working speed of the negative pressure pump 2 determined by this method can ensure that the negative pressure pump 2 can work efficiently and stably under the simulated intake and exhaust pressure. This helps to maintain the normal operation of the engine 1 system and improve the reliability and durability of the system. At the same time, a reasonable speed setting can also reduce the energy consumption and noise of the negative pressure pump 2 and improve the fuel economy and ride comfort of the vehicle.

[0038] In the present application, the method for simulating the intake and exhaust pressures of the engine 1 also includes obtaining the working speed of the air supply pump 4. Obtaining the working speed of the air supply pump 4 specifically includes: obtaining the air supply of the air supply pump 4 based on the maximum air consumption and the air consumption adjustment coefficient of the engine 1. The air supply is a preset value of the actual air consumption required by the engine 1, which takes into account the air consumption demand of the engine 1 under the maximum load, and the air consumption of the engine 1 is appropriately amplified through the air consumption adjustment coefficient; when controlling the air supply pump 4 to work, by adjusting its speed, the output air volume of the air supply pump 4 reaches the preset air supply volume, and the speed at this time is recorded, so as to obtain the speed of the air supply pump 4 when the air supply volume is reached, and use the speed as the working speed of the air supply pump 4.

[0039] In the present application, the value range of the air consumption adjustment coefficient is greater than 1.5, which means that the preset air supply will be greater than the maximum air consumption of the engine 1. Adequate air supply is the basis for the efficient operation of the engine 1 to ensure that there is sufficient air supply during the operation of the engine 1 to avoid performance degradation or failure caused by insufficient air supply, which helps to improve the output power of the engine 1, reduce fuel consumption, and extend the service life of the engine 1.

[0040] In the present application, the air supply of the air supply pump 4 is the product of the maximum air consumption of the engine 1 and the air consumption adjustment coefficient. The air supply design of the air supply pump 4 is based on the actual needs of the engine 1. In order to ensure that the engine 1 can obtain sufficient air supply under various working conditions, a preset value greater than the maximum air consumption of the engine 1 is set. This preset value is obtained by multiplying the maximum air consumption of the engine 1 by the air consumption adjustment coefficient. The air consumption adjustment coefficient of the present application is usually greater than 1.5 to ensure that there is sufficient air supply to cope with changes in the load of the engine 1 and losses during the air supply process.

[0041] During use, the air supply pump 4 is installed to supply air to the pressure stabilizing tank 3 at least 1.5 times of the preset maximum air consumption of the engine 1. The pressure stabilizing tank 3, as the cavity of the fixed container, simulates the atmospheric environment and can directly provide a stable air pressure for the engine 1. At the beginning of the experiment, the altitude is first divided to obtain multiple altitude intervals; then the simulated intake and exhaust pressures are compared with the atmospheric pressure intervals corresponding to each altitude interval, and the altitude interval corresponding to the atmospheric pressure interval where the simulated intake and exhaust pressures are located is found. At this time, based on the upper limit value of the poster altitude interval found, the working speed of the negative pressure pump 2 is confirmed by a preset algorithm or a lookup table. After the negative pressure pump 2 starts working, the air pressure in the pressure stabilizing tank 3 is lower than the external atmospheric pressure, and the pressure sensor detects the difference between the actual air pressure in the pressure stabilizing tank 3 and the simulated intake and exhaust pressure. Finally, the air supply pump 5 is controlled to stabilize the pressure in the pressure stabilizing tank 3 so that the pressure in the pressure stabilizing tank 3 is stable within the simulated pressure range, realizing a high-precision simulation of the intake and exhaust pressure changes of the engine 1, and providing strong support for the performance research and optimization of the engine 1.

[0042] Example 2

[0043] In some alternative embodiments, see Figure 1 The embodiment of the present application provides an engine intake and exhaust simulation system including a pressure stabilizing tank 3, and an air supplement pump 5, an air supply pump 4, a negative pressure pump 2, and a pressure sensor connected to the pressure stabilizing tank 3. The pressure stabilizing tank 3 is connected to the engine 1 through a pipeline, and the pipeline includes an intake pipe 70 and an exhaust pipe 71, and the intake pipe 70 and the exhaust pipe 71 are in a normally open state. When in use, the pressure stabilizing tank 3 is used as a cavity of a fixed container to simulate the atmospheric environment and directly provide a stable air pressure for the engine 1. In specific operation, the air supply pump 4 provides a fixed flow of air pressure to the pressure stabilizing tank 3, the negative pressure pump 2 draws air from the pressure stabilizing tank 3, and finally the air supplement pump 5 is used to inject air into the pressure stabilizing tank 3 to stabilize the air pressure in the pressure stabilizing tank 3, so that the pressure in the pressure stabilizing tank 3 meets the simulated experimental pressure. When conducting tests at different altitudes, there is no need to conduct them in a plateau environment. The simulation experiment can be performed by the pressure stabilizing tank 3, the air supply pump 4, the negative pressure pump 2, and the air supplement pump 5, which is easy to operate.

[0044] In the present application, the engine intake and exhaust simulation system also includes a controller 6, which is connected to the air supplement pump 5, the air supply pump 4, the negative pressure pump 2, and the pressure sensor. The controller 6 is used to determine the working speed of the negative pressure pump 2 under the simulated intake and exhaust pressure based on the intake and exhaust pressure simulated by the engine 1, and the mapping relationship between the working speed of the negative pressure pump 2 and the altitude interval; then, according to the working speed of the negative pressure pump 2, the negative pressure pump 2 is driven to work to pump air into the pressure stabilizing tank 3. The mapping relationship between the working speed of the negative pressure pump 2 and the altitude interval is specifically as follows: the altitude is divided to obtain multiple altitude intervals; the atmospheric pressure corresponding to the upper limit of the altitude in the altitude interval is used as the calibration pressure of the altitude interval, and the calibration pressure represents the approximate range of the atmospheric pressure within the altitude interval; next, the negative pressure pump 2 is controlled to work to obtain the speed of the negative pressure pump 2 when the calibration pressure is reached, and the speed is used as the working speed of the negative pressure pump 2; so according to the working speed of the air supply pump 4, the controller 6 drives the air supply pump 4 to work to supply air to the pressure stabilizing tank 3.

[0045] Based on the actual air pressure in the pressure-surge tank 3 and the simulated intake and exhaust pressure, the air supply pump 5 is driven to work to adjust the pressure-surge tank 3 to the simulated intake and exhaust pressure. In this application, the air supply pump 4 supplies air to the pressure-surge tank 3 according to at least 1.5 times the maximum air consumption of the engine 1, and the negative pressure pump 2 completes its working speed according to the upper limit of the middle altitude of the simulated altitude interval corresponding to the simulated pressure. During use, the pressure in the pressure-surge tank 3 is lower than the atmospheric pressure. When the actual air pressure in the pressure-surge tank 3 does not meet the simulated air pressure, the air supply pump 5 is used to supply air to the pressure-surge tank 3. The solution achieves accurate simulation of the intake and exhaust pressure environment of the engine 1 at different altitudes by accurately controlling the working states of the negative pressure pump 2, the air supply pump 4 and the air supply pump 5, providing strong support for the research and development and testing of the engine 1.

[0046] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the system or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. Unless otherwise expressly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0047] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0048] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A method for simulating engine intake and exhaust, characterized in that: The following steps are involved: Based on the intake and exhaust pressures simulated by the engine (1) and the mapping relationship between the operating speed of the negative pressure pump (2) and the altitude range, the operating speed of the negative pressure pump (2) is determined under the simulated intake and exhaust pressures; According to the working speed of the negative pressure pump (2), the negative pressure pump (2) is driven to work so as to pump gas into the pressure stabilizing tank (3); According to the working speed of the air supply pump (4), the air supply pump (4) is driven to work so as to supply air to the pressure regulating tank (3); Based on the actual air pressure in the pressure-surge tank (3) and the simulated intake and exhaust pressure, the air supply pump (5) is driven to operate so as to adjust the pressure-surge tank (3) to the simulated intake and exhaust pressure.

2. The engine intake and exhaust simulation method according to claim 1, characterized in that: The method further comprises obtaining a mapping relationship between the working speed of the negative pressure pump (2) and the altitude interval, specifically comprising: Divide the altitude to obtain multiple altitude intervals; The atmospheric pressure corresponding to the upper limit of the altitude in the altitude interval is used as the calibration pressure of the altitude interval; Controlling the operation of the negative pressure pump (2) to obtain a rotation speed when the calibrated pressure is reached, and using the rotation speed as the operating rotation speed of the negative pressure pump (2); Based on the calibrated pressure of each altitude interval and the operating speed of the negative pressure pump (2), a mapping relationship between the operating speed of the negative pressure pump (2) and the altitude interval is obtained.

3. The engine intake and exhaust simulation method according to claim 1, characterized in that: Based on the intake and exhaust pressures simulated by the engine (1) and the mapping relationship between the operating speed of the negative pressure pump (2) and the altitude range, the operating speed of the negative pressure pump (2) under the simulated intake and exhaust pressures is determined, specifically including: Compare the simulated intake and exhaust pressures with the atmospheric pressure ranges corresponding to each altitude range; Find the altitude interval corresponding to the atmospheric pressure interval where the simulated intake and exhaust pressures are located; Based on the found mapping relationship between the altitude interval and the operating speed of the negative pressure pump (2) with respect to the altitude interval, the operating speed of the negative pressure pump (2) under the simulated intake and exhaust pressure is determined.

4. The engine intake and exhaust simulation method according to claim 2, characterized in that: Starting from 0m above sea level, the altitude is divided into intervals of 1000m.

5. The engine intake and exhaust simulation method according to claim 1, characterized in that: The method further comprises obtaining the operating speed of the air supply pump (4), wherein obtaining the operating speed of the air supply pump (4) specifically comprises: Based on the maximum air consumption of the engine (1) and the air consumption adjustment coefficient, the air supply volume of the air supply pump (4) is obtained; The air supply pump (4) is controlled to operate so as to obtain a rotation speed when the air supply volume is reached, and the rotation speed is used as the operating rotation speed of the air supply pump (4).

6. The engine intake and exhaust simulation method according to claim 5, characterized in that: The gas consumption adjustment coefficient has a value range of greater than 1.

5.

7. The engine intake and exhaust simulation method according to claim 6, characterized in that: The air supply volume of the air supply pump (4) is the product of the maximum air consumption of the engine (1) and the air consumption adjustment coefficient.

8. The engine intake and exhaust simulation method according to claim 1, characterized in that: The pressure stabilizing tank (3) is provided with a pressure sensor.

9. An engine intake and exhaust simulation system, characterized in that: It comprises a pressure stabilizing tank (3), and an air supplement pump (5), an air supply pump (4), a negative pressure pump (2), and a pressure sensor connected to the pressure stabilizing tank (3).

10. An engine intake and exhaust simulation system as claimed in claim 9, characterized in that: It also includes a controller (6), which is connected to the air supplement pump (5), the air supply pump (4), the negative pressure pump (2), and the pressure sensor, and is used to: determine the operating speed of the negative pressure pump (2) under the simulated intake and exhaust pressure based on the intake and exhaust pressure simulated by the engine (1) and the mapping relationship between the operating speed of the negative pressure pump (2) and the altitude range; drive the negative pressure pump (2) to work according to the operating speed of the negative pressure pump (2) to extract air from the pressure stabilizing tank (3); drive the air supply pump (4) to work according to the operating speed of the air supply pump (4) to supply air to the pressure stabilizing tank (3); drive the air supplement pump (5) to work based on the actual air pressure in the pressure stabilizing tank (3) and the simulated intake and exhaust pressure to adjust the pressure stabilizing tank (3) to the simulated intake and exhaust pressure.

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