A gas mixer, a gas mixing system, a control method, and an engine

Abstract

The present application relates to a kind of gas mixer, gas mixing system, control method and engine, the gas mixer includes first guide tube, second guide tube and cyclone member, first guide tube is arranged in first gas pipeline with first gas pipeline clearance cooperation, the inlet end of first guide tube is communicated with second gas pipeline, outlet end extends to the downstream direction of first guide tube inlet end along the gas flow direction in first gas pipeline;Second guide tube inlet end is arranged in first gas pipeline with first gas pipeline clearance cooperation, outlet end extends into first guide tube;Cyclone member is arranged at the outlet end of first guide tube and / or the outlet end of second guide tube, for the gas in first guide tube inside and outside and in second guide tube is rotated and mixed.Two kinds of gas described above gas mixer can be more fully mixed, and avoid the problem that high-temperature gas in first guide tube contacts low-temperature first gas pipeline and freezes.

Description

Technical Field

[0001] This invention relates to the field of internal combustion engine technology, and in particular to a gas mixer, a gas mixing system, a control method, and an engine. Background Technology

[0002] Exhaust Gas Recirculation (EGR) refers to the cooling of some of the exhaust gas discharged from the engine, its reintroduction into the intake manifold, its mixing with fresh air, and its re-entry into the cylinders for combustion. The EGR gas mixing system can reduce nitrogen oxide emissions, reduce pumping losses under partial load, improve fuel economy, and suppress knocking tendencies.

[0003] Under normal operating conditions, the temperature of EGR exhaust gas is between 70℃ and 180℃. Due to the high water content in EGR exhaust gas, when it encounters the excessively cold inner wall of the intake pipe in a low-temperature environment, the water-holding capacity of the exhaust gas decreases, causing water to precipitate and ice to form on the wall. At this time, the reduced intake airflow area of ​​the engine will affect engine performance.

[0004] In addition, the uniformity of EGR exhaust gas mixing with fresh intake air is strongly correlated with engine performance. However, the mixing effect is often negatively correlated with the EGR exhaust gas outlet resistance; that is, when the mixing uniformity is high, the EGR outlet resistance is high, and when the mixing uniformity is poor, the EGR outlet resistance is low. Specifically, the more openings at the end of the EGR pipe that extend into the air pipe, the better the mixing uniformity, but correspondingly, the greater the EGR outlet resistance. EGR mixing uniformity and EGR outlet resistance are incompatible. Furthermore, EGR mixing uniformity is also related to the intake pipe length and the EGR outlet pipe position.

[0005] Therefore, how to reduce the risk of EGR exhaust gas icing in cold regions, balance the EGR mixing effect with EGR exhaust resistance, and improve engine EGR performance are urgent problems to be solved. Summary of the Invention

[0006] The first objective of this invention is to provide a gas mixer that can reduce the risk of EGR exhaust gas icing in cold regions, balance EGR mixing efficiency with EGR exhaust resistance, and improve engine EGR performance.

[0007] A second objective of the present invention is to provide a gas mixing system, a control method, and an engine that include the gas mixer described above.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] In a first aspect of this application, a gas mixer is provided for mixing two gases in a first gas pipeline and a second gas pipeline connected together, the gas mixer comprising:

[0010] A first guide tube is disposed in the first gas pipe with a clearance fit. The inlet end of the first guide tube is used to communicate with the second gas pipe, and the outlet end extends downstream of the inlet end of the first guide tube along the gas flow direction in the first gas pipe.

[0011] The second guide tube has an inlet end that is fitted with the first gas pipe with a clearance and is positioned inside the first gas pipe, facing the gas flow direction in the first gas pipe. The outlet end extends into the first guide tube and extends towards the outlet end of the first guide tube along the gas flow direction inside the first guide tube.

[0012] A swirling component is disposed at the outlet end of the first guide tube and / or the outlet end of the second guide tube, for causing the gas inside and outside the first guide tube and inside the second guide tube to swirl and mix.

[0013] In one possible implementation, the swirling member is rotatably disposed at the outlet end of the first guide tube and / or the outlet end of the second guide tube, and the swirling member is capable of rotating under the drive of a power source.

[0014] Alternatively, the swirling member may be provided with a rotatable swirling section that can rotate under the drive of a power source.

[0015] In one possible implementation, the power source includes a drive device that is tractively connected to the swirling member or the swirling section to drive the swirling member or the swirling section to rotate.

[0016] In one possible implementation, the swirl member includes:

[0017] The main body of the component is a sleeve-shaped structure that is circumferentially closed and open at both ends. The inlet end of the main body of the component is connected to the outlet end of the first guide pipe and / or the outlet end of the second guide pipe, and the outlet end extends along the gas flow direction.

[0018] A baffle plate is disposed on the inner and outer walls of the main body of the component, and is used to drive the gas inside and outside the first guide pipe and inside the second guide pipe to rotate and mix.

[0019] In one possible implementation, the main body of the component includes a first sleeve portion, a second sleeve portion, and a third sleeve portion connected in sequence. The first sleeve portion is disposed at the outlet end of the first guide pipe and / or the outlet end of the second guide pipe. The second sleeve portion is a cone with a gradually expanding diameter along the direction from the first sleeve portion to the third sleeve portion. The spoiler extends at least from the second sleeve portion to the third sleeve portion.

[0020] In one possible implementation, the spoiler on the inner wall of the component body and the spoiler on the outer wall of the component body are arranged in a circumferentially offset manner.

[0021] In one possible implementation, the swirling member is disposed at the outlet end of the first guide tube, and the outlet end of the second guide tube does not exceed the inlet end of the swirling member.

[0022] In one possible implementation, the inlet end of the second guide tube is provided with a flared structure that gradually widens along the direction from the outlet end to the inlet end of the second guide tube.

[0023] In one possible implementation, the first guide tube includes a first pipe segment and a second pipe segment. The end of the first pipe segment away from the second pipe segment is the inlet end of the first guide tube, and the end of the second pipe segment away from the first pipe segment is the outlet end of the first guide tube. The angle between the first pipe segment and the second pipe segment is an obtuse angle, and the second guide tube extends into the first guide tube from the outer corner of the connection between the first pipe segment and the second pipe segment.

[0024] As can be seen from the above technical solutions, the gas mixer provided by the present invention includes a first guide tube, a second guide tube, and a swirling component. The first guide tube is disposed within the first gas pipe with a clearance fit. The inlet end of the first guide tube is connected to the second gas pipe, and the outlet end extends downstream of the inlet end of the first guide tube along the gas flow direction in the first gas pipe. The inlet end of the second guide tube is disposed within the first gas pipe with a clearance fit and faces the gas flow direction in the first gas pipe. The outlet end extends into the first guide tube and extends towards the outlet end of the first guide tube along the gas flow direction within the first guide tube. The swirling component is disposed at the outlet end of the first guide tube and / or the outlet end of the second guide tube, for rotating and mixing the gases inside and outside the first guide tube and inside the second guide tube.

[0025] The gas mixer described above adopts a sleeve structure and a swirling component is provided at the outlet end of the gas mixer. In this way, the first gas can flow through the gap between the first guide pipe and the first gas pipe and through the second guide pipe, and the second gas can flow through the gap between the first guide pipe and the second guide pipe, forming a sandwich structure with two layers of first gas inside and outside and a layer of second gas in between. The swirling component at the outlet end can make the three layers of gas rotate, thereby making the two gases more fully mixed.

[0026] When the above-mentioned gas mixer is used in the engine's intake system, the first gas pipe is an air pipe, the second gas pipe is an EGR pipe, the gas mixer is located inside the first gas pipe, and the first guide pipe is connected to the second gas pipe. This forms a sandwich structure with two layers of air inside and outside and a layer of EGR gas in between. The swirling component at the outlet end of the gas mixer causes the two layers of air inside and outside and the EGR gas on one side to rotate and mix, avoiding contact between the EGR gas and the air pipe. This prevents the EGR gas from losing its water-carrying capacity due to temperature drop, which could cause water to precipitate in the EGR gas, leading to ice formation on the inner wall of the air pipe and reducing the intake flow area, thus affecting engine performance.

[0027] Furthermore, the outlet end of the first guide pipe used to transport EGR gas extends downstream of the inlet end of the first guide pipe along the gas flow direction in the first gas pipeline, away from the intake throttle valve in the upstream air pipeline. This can increase the mixing effect and prevent EGR gas from being drawn back when the intake throttle valve is closed. Even if a negative pressure is formed, it can only draw back air with the same temperature as the intake throttle valve through the inlet end of the second guide pipe, eliminating the risk of water separation and further reducing the risk of icing.

[0028] In addition, the first guide pipe is a straight-through air pipe, with only a bend in the pipe extending from the inlet end connected to the second gas pipe to the outlet end. The EGR outlet resistance is only the loss of the bend, which can effectively reduce the EGR outlet resistance while ensuring the uniformity of mixing. This allows for the compatibility of EGR mixing effect and EGR outlet resistance, thereby improving the engine's EGR performance.

[0029] In a second aspect of this application, a gas mixing system is provided, including a first gas pipe, a second gas pipe, and a gas mixer as described in the first aspect and its possible implementations. A first guide tube of the gas mixer is disposed within the first gas pipe with a clearance fit. The inlet end of the first guide tube is connected to the second gas pipe, and the outlet end extends downstream of the inlet end of the first guide tube along the gas flow direction in the first gas pipe. The inlet end of the second guide tube of the gas mixer is disposed within the first gas pipe with a clearance fit and faces the gas flow direction in the first gas pipe. The outlet end extends into the first guide tube and extends towards the outlet end of the first guide tube along the gas flow direction in the first guide tube.

[0030] In one possible implementation, the gas mixing system is an engine's EGR intake system, the first gas pipe is an air pipe, and the second gas pipe is an EGR pipe.

[0031] In one possible implementation, the swirling component of the gas mixer is rotatably disposed at the outlet end of the first guide tube and / or the outlet end of the second guide tube, or the swirling component of the gas mixer is provided with a rotatable swirling section;

[0032] The gas mixer also includes a drive device for driving the swirling member or the swirling section to rotate.

[0033] In a third aspect of this application, a control method for a gas mixing system based on a second possible implementation of the second aspect is provided, comprising the steps of:

[0034] a) Obtain EGR flow rate. If the EGR flow rate is 0, output the first signal to the virtual switch. The virtual switch sets the rotation speed of 0 as the rotation speed of the vortex component and outputs it to the drive device. If the EGR flow rate is greater than 0, output the second signal to the virtual switch. The virtual switch sets the required rotation speed as the rotation speed of the vortex component and outputs it to the drive device.

[0035] b) The required speed is obtained by looking up the table based on the EGR flow rate, exhaust gas temperature, exhaust gas pressure, and intake pressure.

[0036] In one possible implementation, step b) includes the step:

[0037] b1) Based on the EGR flow rate and exhaust gas temperature, find the EGR pipeline pressure drop reference table to obtain the EGR pipeline pressure drop value, obtain the exhaust gas pressure value and the inlet pressure value, calculate the difference between the exhaust gas pressure value and the EGR pipeline pressure drop value to obtain the EGR exhaust gas pressure value, and calculate the difference between the EGR exhaust gas pressure value and the inlet pressure value to obtain the pressure difference between the inlet and EGR exhaust gas.

[0038] b2) Based on the pressure difference between the intake air and the EGR exhaust gas and the EGR rate, find the basic speed setting table to obtain the basic speed of the swirl component;

[0039] b3) The basic rotational speed of the swirl component is output as the required rotational speed to the virtual switch, and the virtual switch outputs the required rotational speed as the set rotational speed of the swirl component to the drive device.

[0040] In one possible implementation, step b3) includes the following steps:

[0041] b31) Based on the difference between the ambient temperature and the calibration baseline temperature, look up the speed correction setting table to obtain the speed correction coefficient;

[0042] b32) The base rotation speed of the vortex component is corrected based on the rotation speed correction coefficient, and the corrected base rotation speed of the vortex component is output as the required rotation speed to the virtual switch. The virtual switch outputs the required rotation speed as the set rotation speed of the vortex component to the drive device.

[0043] In a fourth aspect of this application, an engine is provided, including a gas mixing system as described in two possible implementations of the second aspect.

[0044] Since the gas mixing system, control method, and engine employ the gas mixer described in the first aspect and its possible implementations, the gas mixing system, control method, and engine should have the same beneficial effects as the aforementioned gas mixer, which will not be elaborated further here. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a schematic diagram of the structure of a gas mixer provided in an embodiment of the present invention;

[0047] Figure 2 This is a schematic diagram of the structure of a gas mixing system provided in an embodiment of the present invention;

[0048] Figure 3 A partial cross-sectional view of a gas mixing system provided in an embodiment of the present invention;

[0049] Figure 4 This is a schematic diagram of the structure of the EGR intake system provided in an embodiment of the present invention;

[0050] Figure 5 A flowchart of a control method for a gas mixing system provided in an embodiment of the present invention.

[0051] In the picture:

[0052] 100 is a gas mixer; 110 is a first guide pipe; 120 is a second guide pipe; 130 is a swirl component; 140 is a drive device; 200 is a second gas pipeline; 300 is a first gas pipeline. Detailed Implementation

[0053] One of the core aspects of this invention is to provide a gas mixer whose structural design can reduce the risk of EGR exhaust gas icing in cold regions, balance EGR mixing effect with EGR exhaust resistance, and improve engine EGR performance.

[0054] Another core aspect of this invention is to provide a gas mixing system, control method, and engine based on the aforementioned gas mixer.

[0055] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0056] This application provides a gas mixer 100; please refer to [link / reference]. Figures 1 to 3 The gas mixer 100 is used to mix two gases in a gas mixing system. The gas mixing system includes a first gas pipe 300 and a second gas pipe 200 connected to each other. The first gas pipe 300 and the second gas pipe 200 are used to transport two different gases. The gas mixer 100 is used to mix the two gases. The gas mixer 100 includes a first guide pipe 110, a second guide pipe 120, and a swirl member 130.

[0057] The first guide pipe 110 is disposed within the first gas pipe 300 in a clearance fit with the first gas pipe 300 to form an approximately annular flow gap between the first guide pipe 110 and the first gas pipe 300. The inlet end of the first guide pipe 110 is used to communicate with the second gas pipe 200, and the outlet end of the first guide pipe 110 extends downstream of the inlet end of the first guide pipe 110 along the gas flow direction in the first gas pipe 300. That is, the gas flow direction at the outlet end of the first guide pipe 110 is basically consistent with the gas flow direction in the first gas pipe 300.

[0058] The inlet end of the second guide pipe 120 is configured to fit with the first gas pipe 300 within the first gas pipe 300 with a clearance fit, and faces the gas flow direction in the first gas pipe 300. In this way, the gas in the first gas pipe 300 can flow into the inlet end of the second guide pipe 120 and into the gap between the first guide pipe 110 and the first gas pipe 300. The outlet end of the second guide pipe 120 extends into the first guide pipe 110 and extends towards the outlet end of the first guide pipe 110 along the gas flow direction in the first guide pipe 110. That is, the gas flow direction at the outlet end of the second guide pipe 120 is basically consistent with the gas flow direction at the outlet end of the first guide pipe 110.

[0059] Swirl member 130 is disposed at the outlet end of the first guide tube 110 and / or the outlet end of the second guide tube 120, for causing the gas inside and outside the first guide tube 110 and inside the second guide tube 120 to rotate and mix. Swirl member 130 can guide the airflow to rotate, and it includes at least a plurality of turbulence structures evenly distributed in the circumferential direction. The turbulence structure can be a blade or a protrusion, which is not limited here.

[0060] Compared with the prior art, the gas mixer 100 provided in this application embodiment adopts a sleeve structure and a swirling member 130 is provided at the outlet end of the gas mixer 100. This allows the first gas to flow through the gap between the first guide pipe 110 and the first gas pipe 300 and through the second guide pipe 120, while the second gas can flow through the gap between the first guide pipe 110 and the second guide pipe 120, forming a sandwich structure with two layers of first gas inside and outside, and a layer of second gas in between. Figure 3 As shown, the swirl member 130 at the outlet end can rotate the three layers of gas, thereby allowing the two gases to mix more thoroughly.

[0061] When the gas mixer 100 described above is used in the engine's intake system, such as Figure 4 As shown, the first gas pipe 300 is an air pipe, the second gas pipe 200 is an EGR pipe, and the gas mixer 100 is located inside the first gas pipe 300. The first guide pipe 110 is connected to the second gas pipe 200, and the first guide pipe 110 is connected to the first gas pipe 300. This can form a sandwich structure with two layers of air inside and outside and a layer of EGR gas in between. The swirl member 130 at the outlet end of the gas mixer 100 causes the two layers of air inside and outside and the EGR gas on one side in the middle to rotate and mix, avoiding contact between the EGR gas and the air pipe. This prevents the EGR gas from losing its water-carrying capacity due to temperature drop, which could cause water to precipitate in the EGR gas, leading to ice formation on the inner wall of the air pipe and a reduction in the intake flow area, thus affecting engine performance.

[0062] Furthermore, the outlet end of the first guide pipe 110 used to transport EGR gas extends downstream of the inlet end of the first guide pipe 110 along the gas flow direction in the first gas pipeline 300, away from the intake throttle valve in the upstream air pipeline. This can increase the mixing effect and prevent EGR gas from being drawn back when the intake throttle valve is closed. Even if a negative pressure is formed, it can only draw back air with the same temperature as the intake throttle valve through the inlet end of the second guide pipe 120, eliminating the risk of water separation and further reducing the risk of icing.

[0063] In addition, the first guide pipe 110 is a straight-through pipe, with only a bend in the pipe extending from the inlet end connected to the second gas pipe 200 to the outlet end. The EGR outlet resistance is only the bend loss, which can effectively reduce the EGR outlet resistance while ensuring the uniformity of mixing, thereby balancing the EGR mixing effect and the EGR outlet resistance, and thus improving the engine EGR performance.

[0064] Specifically, in one embodiment of this application, the swirling member 130 is rotatably disposed at the outlet end of the first guide pipe 110 and / or the outlet end of the second guide pipe 120, and the swirling member 130 can rotate under the drive of a power source; or, the swirling member 130 is provided with a rotatable swirling section, which can rotate under the drive of a power source. The aforementioned power source can be a drive device 140, which controls the rotational speed of the swirling member 130 or the swirling section thereon, or it can be the gas in the first gas pipe 300 and the second gas pipe 200. The greater the gas flow rate, the faster the swirling member 130 or the swirling section thereon rotates.

[0065] Preferably, in order to enable the gas mixer 100 in this application to adapt to various working conditions, in one embodiment of this application, the power source includes a drive device 140, which is connected to the swirling member 130 or the swirling section to drive the swirling member 130 or the swirling section to rotate, thereby actively controlling the rotation speed of the swirling member 130 or the swirling section to meet the needs under different working conditions.

[0066] Please see Figure 1 In one embodiment of this application, the swirling component 130 includes a component body and a baffle plate. The component body is a sleeve-shaped structure that is circumferentially closed and open at both ends. The inlet end of the component body is connected to the outlet end of the first guide pipe 110 and / or the outlet end of the second guide pipe 120, and the outlet end extends along the gas flow direction. The baffle plate is disposed on the inner wall and outer wall of the component body to drive the gas inside and outside the first guide pipe 110 and inside the second guide pipe 120 to rotate and mix.

[0067] For ease of installation, the main body of the component includes a first sleeve, a second sleeve, and a third sleeve connected in sequence. The first sleeve is located at the outlet end of the first guide pipe 110 and / or the outlet end of the second guide pipe 120. The second sleeve is a cone with a gradually expanding diameter along the direction from the first sleeve to the third sleeve. The spoiler extends at least from the second sleeve to the third sleeve.

[0068] To further optimize the above technical solution, the spoiler on the inner wall of the main body of the component and the spoiler on the outer wall of the main body of the component are staggered in the circumferential direction, so that the main body of the component can be formed by stamping an annular sleeve, which facilitates manufacturing.

[0069] Please continue reading. Figure 1 The swirling component 130 is disposed at the outlet end of the first guide tube 110, and the outlet end of the second guide tube 120 does not exceed the inlet end of the swirling component 130, so as to ensure that the swirling component 130 can drive the gas inside and outside the first guide tube 110 and in the second guide tube 120 to rotate.

[0070] To facilitate the entry of gas from the first gas pipe 300 into the inlet of the second guide pipe 120, in one embodiment of this application, such as... Figure 1 As shown, the inlet end of the second guide pipe 120 is provided with a flared structure that gradually widens from the outlet end to the inlet end of the second guide pipe 120. By increasing the cross-sectional area of ​​the inlet end of the second guide pipe 120, it is easier for the gas in the first gas pipeline 300 to enter the second guide pipe 120.

[0071] like Figure 1 As shown, the first guide pipe 110 includes a first pipe section and a second pipe section. The end of the first pipe section away from the second pipe section is the inlet end of the first guide pipe 110, and the end of the second pipe section away from the first pipe section is the outlet end of the first guide pipe 110. The angle between the first pipe section and the second pipe section is an obtuse angle to reduce the resistance when the gas turns in the first guide pipe 110. The second guide pipe 120 extends into the first guide pipe 110 from the outer corner of the connection between the first pipe section and the second pipe section.

[0072] This application also provides a gas mixing system, such as Figure 2 As shown, the gas mixing system includes a first gas pipeline 300, a second gas pipeline 200, and a gas mixer 100 as described in the above embodiment. The first guide pipe 110 of the gas mixer 100 is disposed in the first gas pipeline 300 with a clearance fit. The inlet end of the first guide pipe 110 is connected to the second gas pipeline 200, and the outlet end extends downstream of the inlet end of the first guide pipe 110 along the gas flow direction in the first gas pipeline 300.

[0073] The inlet end of the second guide tube 120 of the gas mixer 100 is disposed in the first gas pipe 300 with a clearance fit and faces the gas flow direction in the first gas pipe 300. The outlet end extends into the first guide tube 110 and extends towards the outlet end of the first guide tube 110 along the gas flow direction in the first guide tube 110.

[0074] Since the gas mixing system uses the gas mixer 100 in the above embodiments, the technical effects of the gas mixing system can be found in the above embodiments.

[0075] Specifically, such as Figure 4 As shown, in one embodiment, the gas mixing system is the engine's EGR intake system, wherein the first gas pipe 300 is an air pipe and the second gas pipe 200 is an EGR pipe.

[0076] Preferably, the swirling member 130 of the gas mixer 100 is rotatably disposed at the outlet end of the first guide pipe 110 and / or the outlet end of the second guide pipe 120, or the swirling member 130 of the gas mixer 100 is provided with a rotatable swirling section; the gas mixer 100 also includes a driving device 140 for driving the swirling member 130 or the swirling section to rotate, the driving device 140 is used to actively drive the swirling member 130 or the swirling section to rotate, thereby adjusting the mixing effect according to the working conditions and meeting the needs of different working conditions.

[0077] This application embodiment also provides a control method based on the above-described gas mixing system with driving device 140, such as... Figure 5 As shown, the control method includes the following steps:

[0078] a) Obtain EGR flow rate. If the EGR flow rate is 0, output a first signal to the virtual switch. The virtual switch sets the rotation speed of 0 as the rotation speed of the vortex component 130 and outputs it to the drive device 140. If the EGR flow rate is greater than 0, output a second signal to the virtual switch. The virtual switch sets the required rotation speed as the rotation speed of the vortex component 130 and outputs it to the drive device 140.

[0079] The engine's EGR intake system is generally equipped with an air flow sensor or MAF sensor, an air temperature sensor, an EGR flow sensor, an EGR temperature sensor, an exhaust gas (exhaust) pressure sensor, and an intake pressure sensor. The system transmits the detection data to the engine control unit (ECU) in a timely manner so that the ECU can accurately calculate the fuel injection quantity based on the intake air volume, control the intake throttle valve, and control the working state of the drive unit 140.

[0080] b) The required speed is obtained by looking up the table based on the EGR flow rate, exhaust gas temperature, exhaust gas pressure, and intake pressure.

[0081] The required speed can be set based on actual test parameters during the design process of the engine's EGR intake system.

[0082] Specifically, in one specific embodiment of this application, step b) includes the following steps:

[0083] b1) Based on the EGR flow rate and exhaust gas temperature (if the engine is a turbocharged engine, the exhaust gas temperature is the inlet exhaust gas temperature), find the EGR pipeline pressure drop reference table to obtain the EGR pipeline pressure drop value, obtain the exhaust gas pressure value (if the engine is a turbocharged engine, the exhaust gas pressure value is the inlet exhaust gas pressure value) and the intake pressure value (the absolute pressure value in the intake manifold), calculate the difference between the exhaust gas pressure value and the EGR pipeline pressure drop value to obtain the EGR exhaust gas pressure value, and calculate the difference between the EGR exhaust gas pressure value and the intake pressure value to obtain the pressure difference between the intake and EGR exhaust gases.

[0084] The EGR exhaust gas pressure value is obtained by subtracting the EGR pipeline pressure drop value from the exhaust gas pressure value, and the pressure difference between the intake gas and the EGR exhaust gas is obtained by subtracting the EGR exhaust gas pressure value from the intake gas pressure value.

[0085] b2) Based on the pressure difference between the intake and EGR exhaust gases and the EGR rate, find the basic speed setting table to obtain the basic speed of the swirl component 130.

[0086] EGR rate refers to the percentage of EGR exhaust gas mass / flow rate to the total gas mass / flow rate entering the cylinder.

[0087] b3) The basic rotational speed of the swirl component 130 is output as the required rotational speed to the virtual switch, and the virtual switch outputs the required rotational speed as the set rotational speed of the swirl component 130 to the drive device 140.

[0088] It is foreseeable that in cold regions, engines need to maintain intake air temperature, thus introducing more EGR exhaust gas to increase intake air temperature and improve cold start performance. Therefore, the amount of EGR exhaust gas in the engine intake air varies under different ambient temperatures. Regarding this issue, step b3) includes the following steps:

[0089] b31) Based on the difference between the ambient temperature and the calibration base temperature, look up the speed correction setting table to obtain the speed correction coefficient.

[0090] The speed correction setting table is a one-dimensional table stored in the ECU, which can be used to find a unique correction factor based on the difference between the ambient temperature and the calibration baseline temperature.

[0091] It is easy to understand that the base speed of the swirl component 130 is the calibration data of the engine during the development process based on a certain temperature (such as in a cold compartment or cold region). During the calibration process, it is not possible to calibrate for any temperature, but only for several temperature points, that is, the calibration base temperature. However, in actual cold regions or winter, the actual ambient temperature of the engine is variable and will deviate from the calibration base temperature of the engine during the development process, so it needs to be corrected.

[0092] When the ambient temperature is lower than the calibrated baseline temperature during engine development, the temperature difference between the EGR exhaust gas and the wall of the first gas pipe 300 (which is comparable to the ambient temperature) is greater, thus increasing the risk of icing. In this case, the rotation speed of the swirl component 130 needs to be increased to enhance the rotation of the EGR exhaust gas and ensure more thorough mixing of the fresh intake air and the EGR exhaust gas. When the ambient temperature is higher than the calibrated baseline temperature during engine development, the risk of icing is lower, and the rotation speed of the swirl component 130 can be appropriately reduced. Based on this principle, when the ambient temperature is lower than the engine development temperature, the correction factor is greater than 1; when the ambient temperature is higher than the engine development temperature, the correction factor is less than 1 but greater than 0. Correction is then performed by multiplying the correction factor by the baseline rotation speed of the swirl component 130.

[0093] b32) The basic rotational speed of the swirl component 130 is corrected based on the rotational speed correction coefficient, and the corrected basic rotational speed of the swirl component 130 is output as the required rotational speed to the virtual switch. The virtual switch outputs the required rotational speed as the set rotational speed of the swirl component 130 to the drive device 140.

[0094] This reduces the risk of the gas mixer 100 and gas pipelines freezing when starting the engine in cold regions.

[0095] In cold regions where EGR flow increases, the fresh air temperature is low. The temperature difference between the fresh air and the EGR exhaust gas creates a pressure difference, which improves natural mixing. In this case, the rotation speed of the swirl component 130 or the swirl section can be reduced to 60%-80% of the speed under the same conditions in non-cold regions, thus improving the EGR rate while ensuring good mixing.

[0096] The EGR intake system and control method provided in this application can control the speed of the EGR mixing valve according to the different EGR flow rates, which can ensure that the EGR exhaust gas of each cylinder is consistent under different operating conditions.

[0097] This application also provides an engine that includes the gas mixing system described in the above embodiments. Since the engine uses the gas mixing system described in the above embodiments, the technical effects of the engine can be referred to the above embodiments.

[0098] As indicated in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "a," and / or "the" are not specifically singular and may include the plural. Generally, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements. An element defined by the phrase "comprising an..." does not exclude the presence of other identical elements in the process, method, product, or apparatus that includes the element.

[0099] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0100] 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. The same or similar parts between the various embodiments can be referred to each other.

[0101] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A gas mixer for mixing two gases in a first gas pipe (300) and a second gas pipe (200) connected to each other, characterized in that, The gas mixer (100) includes: The first guide pipe (110) is disposed in the first gas pipe (300) with clearance fitting. The inlet end of the first guide pipe (110) is used to communicate with the second gas pipe (200), and the outlet end extends downstream of the inlet end of the first guide pipe (110) along the gas flow direction in the first gas pipe (300). The second guide tube (120) has an inlet end that is fitted with the first gas pipe (300) in a clearance fit and is positioned inside the first gas pipe (300) and faces the gas flow direction in the first gas pipe (300). The outlet end extends into the first guide tube (110) and extends towards the outlet end of the first guide tube (110) along the gas flow direction in the first guide tube (110). A swirling component (130) is disposed at the outlet end of the first guide tube (110) and / or the outlet end of the second guide tube (120) to cause the gas inside and outside the first guide tube (110) and inside the second guide tube (120) to rotate and mix. The swirling component (130) is rotatably disposed at the outlet end of the first guide tube (110) and / or the outlet end of the second guide tube (120), and the swirling component (130) can rotate under the drive of a power source. Alternatively, the swirling component (130) is provided with a rotatable swirling section, which can rotate under the drive of a power source. The swirling component (130) includes: The main body of the component is a sleeve-shaped structure that is circumferentially closed and open at both ends. The inlet end of the main body of the component is connected to the outlet end of the first guide pipe (110) and / or the outlet end of the second guide pipe (120), and the outlet end extends along the gas flow direction. A baffle plate is disposed on the inner and outer walls of the main body of the component, and is used to drive the gas inside and outside the first guide pipe (110) and inside the second guide pipe (120) to rotate and mix. The first guide pipe (110) includes a first pipe segment and a second pipe segment. The end of the first pipe segment away from the second pipe segment is the inlet end of the first guide pipe (110), and the end of the second pipe segment away from the first pipe segment is the outlet end of the first guide pipe (110). The angle between the first pipe segment and the second pipe segment is an obtuse angle. The second guide pipe (120) extends into the first guide pipe (110) from the outer corner of the connection between the first pipe segment and the second pipe segment.

2. The gas mixer according to claim 1, characterized in that, The power source includes a drive device (140), which is connected to the swirling member (130) or the swirling section to drive the swirling member (130) or the swirling section to rotate.

3. The gas mixer according to claim 1 or 2, characterized in that, The main body of the component includes a first sleeve portion, a second sleeve portion, and a third sleeve portion connected in sequence. The first sleeve portion is disposed at the outlet end of the first guide pipe (110) and / or the outlet end of the second guide pipe (120). The second sleeve portion is a cone with a gradually expanding diameter along the direction from the first sleeve portion to the third sleeve portion. The spoiler extends at least from the second sleeve portion to the third sleeve portion.

4. The gas mixer according to claim 1 or 2, characterized in that, The spoiler on the inner wall of the main body of the component is staggered in the circumferential direction from the spoiler on the outer wall of the main body of the component.

5. The gas mixer according to claim 1 or 2, characterized in that, The swirling component (130) is disposed at the outlet end of the first guide tube (110), and the outlet end of the second guide tube (120) does not exceed the inlet end of the swirling component (130).

6. The gas mixer according to claim 1 or 2, characterized in that, The inlet end of the second guide tube (120) is provided with a flared structure that gradually expands from the outlet end to the inlet end of the second guide tube (120).

7. A gas mixing system, characterized in that, It includes a first gas conduit (300), a second gas conduit (200), and a gas mixer (100) as described in any one of claims 1-6.

8. The gas mixing system according to claim 7, characterized in that, The gas mixing system is the engine's EGR intake system, the first gas pipe (300) is an air pipe, and the second gas pipe (200) is an EGR pipe.

9. The gas mixing system according to claim 8, characterized in that, The swirling component (130) of the gas mixer (100) is rotatably disposed at the outlet end of the first guide pipe (110) and / or the outlet end of the second guide pipe (120), or the swirling component (130) of the gas mixer (100) is provided with a rotatable swirling section. The gas mixer (100) also includes a drive device (140) for driving the swirling member (130) or the swirling section to rotate.

10. A control method for the gas mixing system according to claim 9, characterized in that, Including the following steps: a) Obtain EGR flow rate. If the EGR flow rate is 0, output the first signal to the virtual switch. The virtual switch sets the rotation speed of 0 as the rotation speed of the vortex component (130) and outputs it to the drive device (140). If the EGR flow rate is greater than 0, output the second signal to the virtual switch. The virtual switch sets the required rotation speed as the rotation speed of the vortex component (130) and outputs it to the drive device (140). b) The required speed is obtained by looking up the table based on the EGR flow rate, exhaust gas temperature, exhaust gas pressure, and intake pressure.

11. The control method according to claim 10, characterized in that, Step b) includes the following steps: b1) Based on the EGR flow rate and exhaust gas temperature, find the EGR pipeline pressure drop reference table to obtain the EGR pipeline pressure drop value, obtain the exhaust gas pressure value and the inlet pressure value, calculate the difference between the exhaust gas pressure value and the EGR pipeline pressure drop value to obtain the EGR exhaust gas pressure value, and calculate the difference between the EGR exhaust gas pressure value and the inlet pressure value to obtain the pressure difference between the inlet and EGR exhaust gas. b2) Based on the pressure difference between the intake and EGR exhaust gases and the EGR rate, find the basic speed setting table to obtain the basic speed of the swirl component (130); b3) The basic rotational speed of the swirl component (130) is output to the virtual switch as the required rotational speed, and the virtual switch outputs the required rotational speed as the set rotational speed of the swirl component (130) to the drive device (140).

12. The control method according to claim 11, characterized in that, Step b3) includes the following steps: b31) Based on the difference between the ambient temperature and the calibration baseline temperature, look up the speed correction setting table to obtain the speed correction coefficient; b32) The basic rotational speed of the swirl component (130) is corrected based on the rotational speed correction coefficient, and the corrected basic rotational speed of the swirl component (130) is output to the virtual switch as the required rotational speed. The virtual switch outputs the required rotational speed as the set rotational speed of the swirl component (130) to the drive device (140).

13. An engine, characterized in that, Including the gas mixing system as described in claim 8 or 9.

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