Air-assisted injection system and method based on inboard gases of a rotary engine

Abstract

The application provides an air-assisted injection system and method based on a rotor engine internal source gas, the system comprising a compression side gas extraction port arranged on a body wall surface of the rotor engine at a position corresponding to a compression area; an exhaust side gas extraction port arranged at a position directly communicated with or indirectly connected with an exhaust area; a compression side gas extraction pipeline communicated with the compression side gas extraction port and used for extracting high-pressure gas in a compression stroke; an exhaust side gas extraction pipeline communicated with the exhaust side gas extraction port and used for extracting exhaust pulse gas in an exhaust stroke; and a mode switching valve used for controlling the on-off between the compression side gas extraction pipeline and the exhaust side gas extraction pipeline and the air-assisted atomization nozzle, so as to switch between the compression gas-assisted fuel atomization and the exhaust gas-assisted fuel atomization. Through the system provided by the application, the problems of the high-pressure gas source establishment lag in the cold start stage, the large additional power consumption in the normal operation stage, the complex system structure and the low integration degree are solved.

Description

Technical Field

[0001] This application relates to the field of air-assisted injection technology, and in particular to an air-assisted injection system and method based on internal gas of a rotary engine. Background Technology

[0002] Air-assisted injection systems are a type of injection technology that improves fuel atomization quality and promotes mixture formation by introducing compressed gas during fuel injection and using high-speed airflow to shear, break up, and atomize the liquid fuel. For jet fuel, diesel, and other low-volatility, high-viscosity liquid fuels, this technology can, to some extent, compensate for their high viscosity, poor volatility, and difficulty in atomization. Therefore, it has high application value in scenarios such as heavy fuel engines, cold starts, and enhanced combustion. Existing air-assisted injection systems typically use an independent compressed air supply scheme, where a high-pressure air pump or compressor driven by the engine compresses fresh air and sends it to the injector, where it is injected into the combustion chamber along with the fuel. Compressed air is usually used as an auxiliary air source for the injector, continuously supplied during cold starts and pulsed under certain operating conditions, which can improve atomization and combustion stability.

[0003] Since existing air-assisted injection systems are all based on "external compressed high-pressure air sources", their core is to establish atomized air pressure by means of independent air pumps, additional compression mechanisms or special air supply components. As a result, injection systems that rely on external compression components have problems in practical applications, such as delayed establishment of high-pressure air sources during cold start-up, large additional power consumption during normal operation, and complex system structure and low integration. Summary of the Invention

[0004] To address the aforementioned problems, one objective of this invention is to provide an air-assisted injection system and method based on internal gas of a rotary engine, thereby solving the problems of reliance on an external high-pressure source, such as delayed establishment of the high-pressure gas source during cold start-up, large additional power consumption during normal operation, and complex system structure and low integration.

[0005] To achieve one of its objectives, in a first aspect, the present invention provides an air-assisted injection system based on internal gas from a rotary engine, the technical solution of which is: An air-assisted injection system based on internal gas from a rotary engine includes an engine body, an engine rotor located inside the engine body, and a gas-assisted atomizing nozzle, an air inlet, and an exhaust port disposed on the wall of the engine body, communicating with the internal cavity of the engine body. The gas-assisted atomizing nozzle is connected to a fuel supply line. The system also includes: The compression-side air intake is located on the wall surface of the main body at the position corresponding to the compression zone of the inner cavity; The exhaust side air intake is located in a position that is directly or indirectly connected to the exhaust area of ​​the inner cavity; The compression-side air intake line is connected to the compression-side air intake port and is used to extract compressed high-pressure gas during the compression stroke. The exhaust-side air intake pipeline is connected to the exhaust-side air intake port and is used to extract exhaust pulse gas during the exhaust stroke. A mode switching valve is used to switch between a first position and a second position. When the mode switching valve is in the first position, the compression side air intake line is connected to the gas-assisted atomizing nozzle to deliver compressed high-pressure gas to the gas-assisted atomizing nozzle, thereby achieving compressed gas-assisted fuel atomization. When the mode switching valve is in the second position, the exhaust side intake line is connected to the gas-assisted atomizing nozzle to deliver exhaust pulse gas to the gas-assisted atomizing nozzle, thereby achieving exhaust-assisted fuel atomization.

[0006] As one preferred embodiment, the compression-side air intake is located in front of the gas-assisted atomizing nozzle along the rotation direction of the engine rotor; and / or, The exhaust port is used to connect with the exhaust duct, and the exhaust side air intake is located on the exhaust duct.

[0007] As one of the preferred options, an intake valve, a check valve, and a pressure stabilizing tank are respectively installed on the compression side intake pipeline and the exhaust side intake pipeline, and the pressure stabilizing tank is connected to the mode switching valve.

[0008] As one of the preferred solutions, the system also includes a data acquisition unit, which includes at least one of an eccentric shaft angle sensor, an engine speed sensor, a housing temperature sensor, a nozzle air-side pressure sensor, an exhaust pulse pressure sensor, and a compressed air pressure sensor. The exhaust pulse pressure sensor is located on the exhaust side intake pipe, and the compressed air pressure sensor is located on the compressed side intake pipe.

[0009] As one of the preferred solutions, the system also includes: The electronic control unit is connected to various sensors, valves on various pipelines, and mode switching valves; The electronic control unit is used for: It receives status parameters collected by various sensors, determines the current operating condition of the rotary engine and the target combustion chamber under compression stroke, and controls the valves on each pipeline to different opening degrees and switches the control mode switching valve between the first and second positions.

[0010] To achieve the second objective, the present invention provides an air-assisted injection method based on internal gas of a rotary engine, the technical solution of which is: An air-assisted injection method based on internal gas of a rotary engine, relying on the air-assisted injection system based on internal gas of a rotary engine provided in the first aspect of the present invention, the method being applied to an electronic control unit, the method comprising: Obtain the current operating condition of the rotary engine; the current operating condition includes any one of the following: cold start condition, warm-up transition condition, and normal operation condition; In cold start condition, the control mode switching valve is in the first position, the compression side air intake valve on the compression side air intake line is open, and the exhaust side air intake valve on the exhaust side air intake line is closed, so as to deliver compressed high-pressure gas to the gas-assisted atomizing nozzle. During the warm-up transition, the control mode switching valve is in the first position, the exhaust side air intake valve on the exhaust side air intake pipeline is opened, and the compression side air intake valve on the compression side air intake pipeline is closed after a preset time, so as to pre-deliver the exhaust pulse gas to the mode switching valve. Under normal operating conditions, the control mode switching valve is switched to the second position, the compression side air intake valve on the compression side air intake line is closed, and the exhaust side air intake valve on the exhaust side air intake line is opened to deliver the exhaust pulse gas to the gas-assisted atomizing nozzle. Based on the current operating conditions, control the gas-assisted atomizing nozzle to inject fuel, so that the fuel is assisted in atomization by the compressed high-pressure gas or exhaust pulse gas corresponding to the current operating conditions during the injection process.

[0011] As one preferred embodiment, the step of obtaining the current operating condition of the rotary engine then includes: Based on the eccentric shaft angle and the rotor engine speed, identify the target combustion chamber currently located at the injection window; In the cold start condition, controlling the opening of the compression side air intake valve on the compression side air intake line includes: Based on the eccentric shaft angle, the rotor engine speed, and the time required for compressed high-pressure gas to be delivered from the compression side air intake to the gas-assisted atomizing nozzle, the first air intake time when the target combustion chamber passes through the compression side air intake and is within the effective pressure range of the compression stroke is determined. During the first gas intake time, the compression side intake valve on the compression side intake pipeline is opened, so that the high-pressure compressed gas formed in the target combustion chamber during its own compression stroke can assist in atomizing the fuel injected into the target combustion chamber.

[0012] As one preferred embodiment, controlling the gas-assisted atomizing nozzle to inject fuel according to the current operating condition, so that the fuel is assisted in atomization by the compressed high-pressure gas or the exhaust pulse gas corresponding to the current operating condition during injection, includes: In the cold start condition, the gas-assisted atomizing nozzle is controlled to inject fuel at the injection moment that lags behind the first gas intake time and falls into the injection window of the target combustion chamber; wherein, the lag time of the injection moment relative to the first gas intake time is determined based on the rotor engine speed, the volume of the compression-side gas intake line, and the nozzle gas-side pressure build-up time, so as to inject fuel that has completed compressed gas-assisted atomization into the target combustion chamber.

[0013] As one preferred solution, controlling the opening of the exhaust-side intake valve on the exhaust-side intake pipeline includes: Based on the injection time of the target combustion chamber, the delivery time from the exhaust side air intake to the gas-assisted atomizing nozzle, the phase difference between the combustion chamber currently in the exhaust stroke and the target combustion chamber, and the pressure amplitude of the current exhaust pulse gas, a second air intake time is determined that both the arrival timing and pressure amplitude are adapted to the injection requirements of the target combustion chamber. The exhaust-side air intake valve on the exhaust-side air intake pipeline is opened during the second air intake time.

[0014] As one of the preferred solutions, during the warm-up transition period, the exhaust side intake valve on the exhaust side intake pipe is opened, prior to which the following steps are taken: Try to obtain the exhaust pulse gas and use the exhaust pulse gas as the atomizing gas source at at least one injection moment; Obtain the nozzle air-side pressure and exhaust pulse intensity at the corresponding injection moment; When the nozzle air-side pressure and exhaust pulse pressure meet the atomization conditions, the exhaust-side air intake valve on the exhaust-side air intake pipeline is kept in the open state.

[0015] Compared with the prior art, this application has the following advantages: The system and method provided in this application, during the engine cold start phase, utilizes the high-pressure air generated during the compression stroke as a transitional atomizing gas source to achieve rapid pressure build-up and improve the start-up success rate by switching the mode switching valve to the exhaust side air intake pipeline. This eliminates the need to rely on an external compressed air source to improve overall system efficiency. Therefore, without relying on an external compressor to build pressure, the system can utilize the gas generated during different working strokes within the rotary engine as an atomizing gas source, improving the atomization effect of low-volatile fuels during cold starts and low-temperature phases, while significantly reducing the additional power consumption of independent compressor units. In both cold and hot engine modes, the same gas-assisted atomizing nozzle completes the injection, resulting in a simple and highly integrated system structure, which is highly beneficial for atomization injection in single-rotor engines. Attached Figure Description

[0016] To more clearly illustrate the technical solution of this application, the drawings used in the description of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a system framework diagram of an air-assisted injection system based on internal gas of a rotary engine according to an embodiment of this application; Figure 2 This is a flowchart of the steps of an air-assisted injection system based on internal gas of a rotary engine according to an embodiment of this application.

[0018] Explanation of reference numerals in the attached figures: 1. Fuel tank; 2. Fuel supply line; 3. Exhaust side intake line; 4. Atomizing gas pressure sensor; 5. Engine body; 6. Intake valve; 7. Engine rotor; 8. Housing temperature sensor; 9. Check valve; 10. Exhaust passage; 11. Eccentric shaft; 12. Intake port; 13. Eccentric shaft angle sensor; 14. Spark plug; 15. Compression side intake line; 16. Pressure regulator; 17. Mode switching valve; 18. Intake manifold; 19. Gas-assisted atomizing nozzle; 20. Electronic control unit. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] To better understand the technical solution of this application, common air-assisted injection systems will now be described: Existing air-assisted injection technologies rely on an external high-pressure compressed air source, all requiring additional air supply methods to generate the necessary atomized gas pressure. For example, some solutions use an engine-driven compressor to generate compressed air, coupled with a corresponding control system to supply the gas. Other solutions, while not using a separate external air pump, require a dedicated compression mechanism within the engine, such as a compression piston or cylinder, to provide the compressed gas needed for injection. Furthermore, some solutions introduce engine exhaust as an auxiliary air source or incorporate auxiliary heating devices into the air-assisted injection structure to improve low-temperature starting performance and promote fuel evaporation. Therefore, traditional optimizations of air-assisted injection primarily focus on improving the air supply method, implementing a dedicated compression mechanism, and utilizing or enhancing exhaust gas heating.

[0021] However, due to its reliance on an external high-voltage source, the current technical solution inevitably suffers from the following problems in practical applications: 1. Delayed establishment of compressed high-pressure air source during cold start. For air-assisted injection systems that use engine-driven high-pressure air pumps or compressors, the air source pressure needs to be established first during engine start-up. Only after the air reservoir and air supply lines reach the set pressure can the injectors obtain sufficient atomized gas. Therefore, in low-temperature environments or when the engine is cold, the compressed high-pressure air source often cannot be established quickly at the moment of start-up, making it difficult to meet the strong atomization requirements of low-volatility, high-viscosity fuels such as jet fuel and diesel in a timely manner. This results in insufficient fuel atomization, increased ignition delay, and difficulty in achieving stable initial ignition during the start-up phase.

[0022] 2. Significant additional power consumption during normal operation. Existing air-assisted injection systems typically require the engine to continuously drive a high-pressure air pump, compressor, or other dedicated air supply mechanism to provide compressed air. This component, as an additional load, consumes engine output power, increases mechanical losses and system energy consumption, and is detrimental to improving overall engine thermal efficiency. Especially for rotary engines and two-stroke engines, which emphasize compact structure, power density, and lightweight design, the additional configuration of a separate high-pressure air supply system not only consumes power, but the additional compressor mechanism also reduces the engine's power-to-weight ratio.

[0023] 3. The system structure is complex and lacks integration. Existing solutions often require high-pressure air pumps, air tanks, control valve groups, pressure stabilizing components, and corresponding pipelines. Some solutions even introduce dedicated compression pistons, compression cylinders, or exhaust gas auxiliary circuits, increasing the number of components in the entire gas-assisted injection device, requiring more space, complicating control logic, raising manufacturing costs, and increasing potential failure points. For single-rotor three-chamber engines, continuing to use the traditional external air supply approach not only limits the layout but also fails to fully utilize the clear phase relationship of the rotor engine's working chambers and the obvious exhaust pulse characteristics.

[0024] In view of this, one or more embodiments of the present invention aim to provide an air-assisted atomizing injection system and its control method particularly suitable for rotary engines. This system eliminates the traditional path of establishing a compressed high-pressure gas source using an independent air pump or dedicated pressurization device. Based on the working phase relationship of the rotary engine, a phase-matched exhaust pulse is introduced as the atomizing gas source during normal operation, and compressed high-pressure gas from the compression stroke of the working chamber is introduced as a transitional atomizing gas source during cold start. Through a phase distribution assembly, a switching valve, and a buffer pressure stabilizing structure, the aforementioned gas is introduced into the gas channel of the gas-assisted atomizing nozzle 19 for high-pressure atomizing injection of high-viscosity fuel. Thus, enhanced atomization of high-viscosity fuel can be achieved without an independent high-pressure air pump, which not only shortens the cold start response time and reduces system complexity and additional power consumption, but also helps to improve the combustion stability and system efficiency of the rotary engine.

[0025] To facilitate understanding later, we will first describe the structure, working area / cavity, and combustion chamber of the rotary engine: A rotary engine typically includes a housing structure and an internal engine rotor 7. The inner wall of the housing structure has an approximately elliptical profile. The sides of the housing are equipped with an air intake 12, an exhaust port, an injection port, and a spark plug 14 for air intake, exhaust gas discharge, air-assisted atomization fuel injection, and combustion. The engine rotor 7 is typically a triangular rotor with an outer contour that is approximately an equilateral triangle with curved sides. Sealing strips (corner seals) are provided at the three vertices. The three curved sides of the engine rotor 7, together with the inner wall of the housing and the end caps, form a sealed inner cavity. Driven by an eccentric shaft 11, the engine rotor 7 rotates within the inner cavity and maintains sealed contact with the housing, thereby dividing the inner cavity into multiple sealed spaces with periodically changing volumes as it rotates. These sealed spaces are typically called combustion chambers.

[0026] The intake port 12, the gas-assisted atomizing nozzle 19, and the exhaust port, among other functional components, are all located on the housing wall, and their positions relative to the housing are fixed. As the engine rotor 7 rotates, its three surfaces pass through these fixed functional components, sequentially experiencing the four typical working strokes: intake, compression, power, and exhaust. Correspondingly, based on the housing position, the internal cavity can be further divided into intake, compression, power, and exhaust zones / cavities along the rotor's rotation direction. The positions of each working zone / cavity relative to the housing are known and fixed, used to define the combustion chamber's functional strokes within the rotor's rotation cycle: the intake zone corresponds to the intake stroke, the compression zone to the compression stroke, the power zone to the power stroke, and the exhaust zone to the exhaust stroke.

[0027] As mentioned earlier, the engine rotor 7 is a triangular rotor with three convex arc-shaped edges (profiles). Based on the rotor profile, the three profiles form sealed spaces with the inner wall of the housing and the end cover respectively during rotation. Therefore, each combustion chamber (corresponding to one profile) periodically passes through four working zones during rotation. In other words, at any given moment, there is a combustion chamber operating in any working zone. In a complete cycle, the three combustion chambers will sequentially experience the intake stroke, compression stroke, power stroke, and exhaust stroke in each working zone.

[0028] The technical solutions of one or more embodiments of the present invention will be described in more detail below with reference to several embodiments and accompanying drawings: Reference Figure 1 As shown, Figure 1 This is a system framework diagram illustrating an air-assisted injection system based on internal gas from a rotary engine, for one or more embodiments of the present invention. Figure 1 As shown, one or more embodiments of the present invention provide an air-assisted injection system based on internal gas of a rotary engine, including an engine body 5, an engine rotor 7 disposed inside the engine body 5, and a gas-assisted atomizing nozzle 19, an air inlet 12, and an exhaust port disposed on the wall of the engine body 5, communicating with the inner cavity of the engine body 5. The gas-assisted atomizing nozzle 19 is connected to a fuel supply line 2. The system includes: a compression-side air intake port disposed on the wall of the engine body corresponding to the compression zone of the inner cavity; an exhaust-side air intake port disposed at a position directly or indirectly connected to the exhaust zone of the inner cavity; and a compression-side air intake line 15 connected to the compression-side air intake port for extracting air from the compressed air. The compressed high-pressure gas during the compression stroke; the exhaust-side air intake line 3, connected to the exhaust-side air intake port, is used to extract the exhaust pulse gas during the exhaust stroke; the mode switching valve 17 is used to switch between a first position and a second position; when the mode switching valve 17 is in the first position, the compressed-side air intake line 15 is connected to the gas-assisted atomizing nozzle 19 to deliver the compressed high-pressure gas to the gas-assisted atomizing nozzle 19 to achieve compressed gas-assisted fuel atomization; when the mode switching valve 17 is in the second position, the exhaust-side air intake line 3 is connected to the gas-assisted atomizing nozzle 19 to deliver the exhaust pulse gas to the gas-assisted atomizing nozzle 19 to achieve exhaust gas-assisted fuel atomization.

[0029] Specifically, the engine body 5 can be the aforementioned housing structure of a rotary engine, including a gas-assisted atomizing nozzle 19, an air intake 12, and an exhaust port on the engine body 5. Continuing from the previous description, the combustion chamber's spatial position changes continuously with the rotor's movement, but the functional areas of each working zone on the housing are relatively fixed. The air intake 12 is located on the housing wall corresponding to the intake zone, and is used to communicate with the intake duct to introduce air or a mixture into the intake zone. After entering the working chamber, the air rotates with the rotor and enters the compression zone, where it is gradually compressed. The exhaust port is located on the housing wall corresponding to the exhaust zone, and is used to communicate with the exhaust duct 10 to discharge combustion exhaust gases. In some embodiments, the air intake 12 and the exhaust port can also be arranged in an end-face configuration, positioned on the end cap wall corresponding to the working zone.

[0030] A gas-assisted atomizing nozzle 19 is installed on the casing wall or body wall corresponding to the compression zone. The gas-assisted atomizing nozzle 19 is connected to both the combustion chamber and the fuel supply line 2. The nozzle includes a central fuel passage and a peripheral annular passage. The central fuel passage is connected to the fuel supply line 2, and the peripheral annular passage introduces atomizing gas. The fuel supply line 2 is equipped with a fuel tank 1, a fuel pump, a filter unit, a metering / stop unit, etc., to supply jet fuel, diesel fuel, or other low-volatility, high-viscosity liquid fuels to the central fuel passage of the gas-assisted atomizing nozzle 19. Thus, when any type of combustion chamber enters the compression zone with the rotor and passes through the gas-assisted atomizing nozzle 19, the gas in the combustion chamber during the compression stroke has high pressure and high temperature conditions. The gas-assisted atomizing nozzle 19 injects fuel during the compression stroke of each combustion chamber and introduces high-pressure gas to shear, break up, and atomize the fuel, ensuring thermal efficiency and combustion stability.

[0031] The improvement in this embodiment lies in the provision of a compression-side air intake, an exhaust-side air intake, and a compression-side air intake pipe 15 and an exhaust-side air intake pipe 3. In this embodiment, the compression-side air intake is located on the wall of the engine body 5 corresponding to the compression zone, thus allowing for the extraction of high-pressure and relatively stable compressed high-pressure gas during the compression stroke. The specific location of the air intake can be optimized based on the rotor geometry, working chamber distribution, and gas distribution phase to ensure that high-pressure and stable gas can be obtained during the corresponding stroke stage. The compression zone, from front to back, corresponds to the early to late stages of the compression stroke, during which the gas is gradually compressed and the pressure continuously increases. For example, the front end of the compression zone corresponds to the initial compression stage, where the gas pressure is low; while the rear end of the compression zone corresponds to the late compression stage, where the gas pressure is close to the peak value. Therefore, by selecting different locations on the housing wall along this direction to provide compression-side air intakes, gas can be obtained at different compression stages. Exemplarily, the specific arrangement of the compression-side air intake can include, but is not limited to, the following: located at any position between the front end, middle, middle-rear end, or above of the compression zone.

[0032] Preferably, the compression-side air intake is located in front of the gas-assisted atomizing nozzle 19 along the rotation direction of the engine rotor 7. Typically, the gas-assisted atomizing nozzle 19 is positioned at the middle to rear end of the compression zone, closer to the start of the power zone, and facing the rotor cavity or the main combustion zone. Therefore, the compression-side air intake can preferably be located on the body wall at any position from the front to the middle of the compression zone. Thus, by placing the compression-side air intake on the housing wall in front of the nozzle, the compression-side air intake corresponds to the initial, middle, or any stage in the compression stroke, while the gas-assisted atomizing nozzle 19 corresponds to the stage in the compression stroke later than the air intake time. Therefore, as the rotor rotates, each combustion chamber first passes through the compression-side air intake area, where compressed gas is extracted and the pipeline is pressurized; subsequently, as the rotor continues to rotate, the combustion chamber moves to the position of the gas-assisted atomizing nozzle 19, where fuel injection and gas-assisted atomization are performed, satisfying the "air intake first, injection later" timing requirement.

[0033] It is worth mentioning that, in this embodiment, the above arrangement forms a spatial sequence of "air intake port in front, nozzle behind", which naturally corresponds to a temporal phase matching relationship of "air intake first, then injection". Therefore, the original optimal injection timing and nozzle setting position parameters of the rotary engine can be maintained. There is no need to design complex control logic or rely on additional time control mechanisms. The natural timing matching of air source acquisition and its own injection process can be achieved by utilizing the rotor's own movement.

[0034] Preferably, the air intake on the compression side is arranged in the middle area between the front end and the middle end of the compression zone, so as to obtain high-pressure compressed gas while ensuring that the air intake time is before the injection, thereby improving the gas-assisted atomization effect.

[0035] Furthermore, the exhaust-side air intake is located at a position directly or indirectly connected to the exhaust zone. This position includes the area where the high-temperature, high-pressure exhaust gas can be discharged after or during the power stroke. The gas in this area typically has high instantaneous pressure and pulsating characteristics during the exhaust stroke, which can be used to obtain high-pressure exhaust pulses. For example, the exhaust-side air intake can be located on the body wall corresponding to the exhaust zone and directly connected to the exhaust zone. In this way, the exhaust-side air intake can be located near the exhaust port. Another example is that an exhaust-side air intake is set on the wall of the exhaust passage 10 downstream of the exhaust port fixed on the engine housing wall, connecting to the exhaust zone through the exhaust passage 10, rather than on the housing wall. This allows direct use of the compressed high-pressure gas generated at the end of the exhaust stroke without interfering with the housing structure, avoiding additional openings on the housing, simplifying the structure, and realizing exhaust-assisted injection.

[0036] Furthermore, the compression-side air intake port is connected to the compression-side air intake pipeline 15, which guides the high-pressure air during the compression stroke to the subsequent gas-assisted atomizing nozzle 19. The exhaust-side air intake port is connected to the exhaust-side air intake pipeline 3, which guides the high-pressure pulse gas during the exhaust stroke to the gas-assisted atomizing nozzle 19. An air intake valve 6, a check valve 9, and a pressure stabilizing tank 16 are respectively installed on the compression-side air intake pipeline 15 and the exhaust-side air intake pipeline 3. The pressure stabilizing tank 16 is connected to the mode switching valve 17, allowing the compressed high-pressure gas and the exhaust pulse gas to pass through the exhaust-side air intake valve, the check valve 9, and the buffer pressure stabilizing assembly before being sent to the mode switching valve 17. Specifically, the compression-side air intake pipeline 15 is equipped with a compression-side air intake valve, a compression-side check valve 9, and a compression-side pressure stabilizing tank 16, and the exhaust-side air intake pipeline 3 is equipped with an exhaust-side air intake valve, an exhaust-side check valve 9, and an exhaust-side pressure stabilizing tank 16. The compression-side pressure stabilizing tank 16 and the exhaust-side pressure stabilizing tank 16 are connected one-to-one to the two inlets of the mode switching valve 17 via corresponding pipelines. By using the check valve 9 and the buffer pressure stabilizing tank 16, backflow prevention, peak reduction, pulse shaping, and pressure stabilization can be performed on the exhaust pulse gas or compressed high-pressure gas, so that the gas pressure in the outer annular channel of the nozzle is more suitable for gas-assisted atomization.

[0037] A mode switching valve 17 is located between the compression-side air intake line 15 and the exhaust-side air intake line 3, and the gas-assisted atomizing nozzle 19. The mode switching valve 17 controls the on / off relationship between the two air intake lines and the gas-assisted atomizing nozzle 19, switching between compression-side and exhaust-side air supply modes. The mode switching valve 17 typically has two input terminals and one output terminal. One input terminal is connected to the compression-side air intake line 15; the other input terminal is connected to the exhaust-side air intake line 3; and the output terminal is connected to the outer annular channel of the gas-assisted atomizing nozzle 19 via the main air intake pipe 18.

[0038] The mode switching valve 17 can select the connection between two input and output terminals. When the mode switching valve 17 is in the first position, the first input terminal is connected to the output terminal, while the second input terminal is disconnected from the output terminal. This connects the compression-side air intake line 15 with the gas-assisted atomizing nozzle 19, and disconnects the exhaust-side air intake line 3 from the gas-assisted atomizing nozzle 19. At this time, the compressed high-pressure gas generated during the compression stroke is delivered to the gas-assisted atomizing nozzle 19 through the mode switching valve 17, preventing exhaust pulse gas from entering the nozzle, thus achieving compressed gas-assisted atomization during cold start or low-speed operation. When the mode switching valve 17 is switched to the second position, the first input terminal is disconnected from the output terminal, while the second input terminal is connected to the output terminal. This disconnects the compression-side air intake line 15 with the gas-assisted atomizing nozzle 19, while connecting the exhaust-side air intake line 3 to the gas-assisted atomizing nozzle 19. At this time, the high-pressure pulse gas generated during the exhaust stroke is guided to the gas-assisted atomizing nozzle 19, achieving exhaust gas-assisted atomization during normal operation, preventing compressed high-pressure gas from entering the nozzle.

[0039] In some embodiments, the mode switching valve 17 can be an electronically controlled three-way valve, etc. For example, a solenoid valve or an electric proportional valve controlled by an electronic control unit can be used, and the switching between the first position and the second position can be automatically triggered by the ECU to realize dynamic switching of different operating stages of the engine.

[0040] In summary, during the engine cold start phase, the exhaust-side air source has not yet formed a stable pulse pressure. The mode switching valve 17 can be used to open the compression-side air intake line 15, utilizing the high-pressure air generated during the compression stroke as a transitional atomizing air source to achieve rapid pressure build-up and improve the start-up success rate. After the engine enters the stable operation phase, the exhaust-side air source forms a pulse gas with high kinetic energy. At this time, the mode switching valve 17 switches to the exhaust-side air intake line 3, utilizing its own exhaust pulse gas to achieve efficient atomization, thus eliminating the need to rely on an external compressed air source to improve the overall system efficiency. Through the above structure, this application can utilize the gas generated by different working strokes inside the rotary engine as an atomizing air source without relying on an external compressor to build pressure, improving the atomization effect of low-volatile fuels in the cold start and low-temperature phases of the rotary engine, while significantly reducing the additional power consumption caused by independent compressor devices. In both cold and hot engine modes, the same gas-assisted atomizing nozzle 19 ultimately completes the injection. The system structure is simple and highly integrated, which is highly beneficial for atomization injection in single-rotor engines.

[0041] It is important to emphasize that, during normal engine operation, compared to the cold start phase where high-pressure air generated during the compression stroke is used as the atomizing gas source, using the high-pressure pulse gas generated during the exhaust stroke of the rotary engine as the auxiliary atomizing gas source offers the technical advantage of not relying on an external compressor for compression. Furthermore, it reduces dependence on an internal compression source, thereby further improving the overall system efficiency. Therefore, during normal operation, it avoids weakening the compressed air and air-fuel ratio during the effective power stroke phase, and will not affect the engine's power output, compression efficiency, or overall performance.

[0042] In conjunction with the above embodiments, the system further includes a data acquisition unit and an electronic control unit 20. The data acquisition unit is used to detect and acquire the current engine status parameters. For example, it may include an eccentric shaft angle sensor 13 mounted on the engine eccentric shaft 11, an engine speed sensor mounted on the engine output shaft, a housing temperature sensor 8 mounted near the corresponding working area on the body wall, a nozzle air-side pressure sensor and an atomizing gas pressure sensor 4 mounted on the air-side main pipe or annular channel of the gas-assisted atomizing nozzle 19, including an exhaust pulse pressure sensor mounted on the exhaust pipe and a compressed air pressure sensor mounted on the compression-side intake pipe 15. Each sensor is connected to the electronic control unit 20 via a signal line or a CAN bus to achieve closed-loop control of compressed air, exhaust pulse air, and fuel injection jet. The electronic control unit 20 is the ECU corresponding to the engine. Based on the detected status parameters, such as the eccentric shaft angle, the pressure information of each pipeline, and the temperature information of each air source, it performs related actions such as cold start air-assisted injection, hot engine air-assisted injection, and mode switching. It is also used to identify the operating conditions, identify the target combustion chamber, determine the air intake time window, control the compression side air intake valve, the exhaust side air intake valve, the mode switching valve 17, and the nozzle injection control, etc.

[0043] Correspondingly, such as Figure 2 As shown, Figure 2 This application provides a flowchart of an air-assisted injection system based on internal gas from a rotary engine. Specifically, it offers an air-assisted injection method based on internal gas from a rotary engine, relying on the gas-assisted atomizing nozzle 19 system provided in one or more embodiments of the first aspect of this invention. This method is applied to an ECU and includes the following steps: S1. Obtain the current operating condition of the rotary engine; the current operating condition includes any one of the following: cold start condition, warm-up transition condition, and normal operation condition; First, the electronic control unit 20 acquires the status parameters of the rotary engine and determines the operating condition based on these parameters. The operating condition can be determined based on one or more parameters such as engine speed, engine casing temperature, throttle opening, eccentric shaft angle, intake air temperature, exhaust pulse pressure, and casing temperature, and is divided into cold start condition, warm-up transition condition, and normal operation condition.

[0044] After the ECU is powered on, the data acquisition unit detects and collects the engine's status parameters, preferably including engine housing temperature, eccentric shaft angle, and exhaust pulse peak pressure. In some cases, it also collects the current ambient temperature, compression-side pipeline peak pressure, and stable ignition indicator. The engine housing temperature is collected by housing temperature sensor 8, the eccentric shaft angle by eccentric shaft angle sensor 13, the exhaust pulse peak pressure by exhaust pulse pressure sensor, and the current ambient temperature by a temperature sensor. The compression-side pipeline peak pressure is collected by a compressed air pressure sensor. The stable ignition indicator Fstb is defined as the engine remaining running for several consecutive injection cycles with repeatable periodic exhaust pulses. This indicator is obtained by analyzing the pressure pulses collected by the corresponding exhaust pulse pressure sensor and the engine speed and eccentric shaft angle signals collected by the engine speed sensor.

[0045] For example: Cold start condition: A cold start condition can be determined when any of the following conditions are met: a start signal has been received, but stable ignition has not yet been established; shell temperature < T1; exhaust pulse peak pressure < PE1. T1 can be taken as 50~70℃, and PE1 can be taken as 0.03~0.08MPa(g).

[0046] Warm-up transition condition: When stable ignition has been established, but the exhaust pulse has not yet reached the stable gas supply requirement, it is judged as a transition state. The preferred criteria are: Fstb=1, T1≤shell temperature<T2, PE1≤exhaust pulse peak pressure<PE2. T2 can be taken as 90~130℃, and PE2 can be taken as 0.08~0.15MPa(g).

[0047] Normal operating conditions: When the engine has established stable combustion, and the exhaust pulse intensity, casing temperature, and speed all meet the normal operating requirements, the system is determined to be in a hot-engine or normal operating state. The preferred criteria are: Fstb=1, casing temperature ≥T2, and exhaust pulse peak pressure ≥PE2 continuously for several injection events.

[0048] This can be adjusted based on the prototype and actual fuel characteristics. If the cold start criterion is not met, the engine can directly enter the warm engine / normal operation start mode.

[0049] S2. In the case of cold start, the control mode switching valve 17 is in the first position, the compression side air intake valve on the compression side air intake line 15 is opened, and the exhaust side air intake valve on the exhaust side air intake line 3 is closed, so as to deliver compressed high-pressure gas to the gas-assisted atomizing nozzle 19. During a cold start, because the engine has not yet formed a stable exhaust pulse and the fuel viscosity is high, making atomization difficult, the ECU control mode switching valve 17 is in the first position. Simultaneously, the compression-side air intake valve on the compression-side air intake line 15 is opened, and the exhaust-side air intake valve on the exhaust-side air intake line 3 is closed. This allows the high-pressure air obtained during the compression stroke to be delivered to the gas-assisted atomizing nozzle 19 via the compression-side air intake line 15. During this stage, the high-pressure air serves as the atomizing gas source, achieving the compression-side atomization mode.

[0050] S3. In the warm-up transition condition, the control mode switching valve 17 is in the first position, the exhaust side air intake valve on the exhaust side air intake pipeline 3 is opened to pre-deliver the exhaust pulse gas to the mode switching valve 17, and the compression side air intake valve on the compression side air intake pipeline 15 is closed after a preset time to stop the delivery of compressed high pressure gas within a preset time. During the warm-up transition, as the engine gradually warms up and enters a stable combustion state, an airflow with certain pressure and pulsating characteristics begins to form on the exhaust side. The compression side remains the primary air supply source, and the exhaust side enters a pre-pipe state. At this time, the ECU still controls the mode switching valve 17 to remain in the first position, while first opening the exhaust side intake valve on the exhaust side intake pipe 3 and delaying the closing of the compression side intake valve, allowing the exhaust pulse air to pre-enter the mode switching valve 17 and related pipes to complete filling and establishment. Within this preset time, the compression side air source still serves as the atomizing air source and completes the withdrawal of the compression side air source at the end, while simultaneously establishing the exhaust side air source. This avoids pressure fluctuations or air supply interruptions during the air source switching process, thereby achieving a smooth transition from compressed air to exhaust pulse air.

[0051] In this embodiment, the method of stopping the compressed high-pressure gas within a preset time may include, but is not limited to: gradually reducing the supply volume or pressure of compressed high-pressure gas by controlling the opening of the compression-side air intake valve through the ECU until the compression-side air intake valve is completely closed at the end of the preset time, at which point the mode switching valve 17 is switched from the first position to the second position. Alternatively, the compression-side air intake valve can be directly closed at the last moment of the preset time, while the mode switching valve 17 is switched from the first position to the second position.

[0052] The preset time can be dynamically adjusted according to different state parameters, but this embodiment does not limit it.

[0053] More preferably, during this warm-up transition condition, the ECU can perform exhaust pulse sampling within the effective time window on the exhaust side. Within the effective time window corresponding to each combustion chamber passing the exhaust side intake port, the exhaust side intake valve is briefly opened to sample the exhaust pulse gas, correspondingly briefly switching the position of the mode switching valve 17. The sampled exhaust pulse gas is then used as the atomizing gas source for one or more injection moments. After sampling, the mode switching valve 17 is switched back to the first position. During the auxiliary atomization injection phase using the sampled exhaust pulse gas, the nozzle air-side pressure and exhaust pulse intensity are monitored by the nozzle air-side pressure sensor and the exhaust pulse pressure sensor to determine whether the sampled exhaust pulse gas meets the auxiliary atomization conditions. For example, the fluctuation amplitude of the nozzle air-side pressure after each injection is within a preset allowable range and / or the nozzle air-side pressure reaches or exceeds the minimum pressure threshold required for atomization, and the exhaust pulse pressure exhibits repeatable periodic peaks when each combustion chamber passes the exhaust side intake port and / or the exhaust pulse pressure is higher than the minimum pressure threshold required for exhaust auxiliary atomization. If, in several consecutive injection events, both the nozzle air-side pressure and the exhaust pulse intensity meet the above conditions, it can be determined that the exhaust pulse gas has met the atomization injection requirements, serving as a condition for auxiliary atomization from the formal exhaust gas source. Once the exhaust pulse gas source is determined to be available, the exhaust-side intake valve can be opened, allowing the exhaust pulse gas to begin flowing to the mode switching valve 17, pre-pressurizing the exhaust-side intake pipeline 3. After a preset time, the mode switching valve 17 switches from the first position to the second position, allowing the pressurized exhaust pulse gas to quickly enter the compression zone.

[0054] S4. Under normal operating conditions, the control mode switching valve 17 is switched to the second position, the compression side air intake valve on the compression side air intake line 15 is closed, and the exhaust side air intake valve on the exhaust side air intake line 3 is opened to deliver the exhaust pulse gas to the gas-assisted atomizing nozzle 19. Under normal operating conditions, the engine has generated a stable exhaust pulse airflow with high kinetic energy. The ECU mode switching valve 17 switches to the second position, simultaneously closing the compression-side intake valve on the compression-side intake line 15 while keeping the exhaust-side intake valve on the exhaust-side intake line 3 open, allowing the exhaust pulse gas to be delivered as an atomizing gas source to the gas-assisted atomizing nozzle 19. During this stage, the high pressure and high speed characteristics of the exhaust pulse gas are utilized to achieve efficient fuel shearing and atomization, avoiding reliance on external compression power consumption and not affecting the power output of the internal compressed gas, effectively improving the overall system efficiency.

[0055] S5. Based on the current operating conditions, control the gas-assisted atomizing nozzle to inject fuel, so that the fuel is assisted in atomization by the compressed high-pressure gas or the exhaust pulse gas corresponding to the current operating conditions during the injection process.

[0056] Combining steps S1-S4, under any operating condition, the ECU controls the injection parameters of the gas-assisted atomizing nozzle 19, including injection timing, fuel injection quantity, injection duration, and injection method. Regardless of whether the atomizing gas comes from the compression side or the exhaust side, it ultimately enters the outer annular air passage of the same gas-assisted atomizing nozzle 19, and within the effective window of the compression stroke, the gas-assisted atomizing nozzle 19 is responsible for injecting the fuel jet (a mixture of fuel and airflow) that has been atomized by the airflow.

[0057] Therefore, during a cold start, the ECU opens the compression-side intake valve when each combustion chamber rotates to the compression zone and is within the compression stroke intake window, allowing the high-pressure compressed air from each combustion chamber to enter the annular air passage surrounding the nozzle. During a warm-up or normal operation, the ECU extracts the high-pressure exhaust pulse when each combustion chamber rotates to the exhaust zone and is within the exhaust stroke intake window, then sends it into the annular air passage surrounding the nozzle. During a cold start, the high-pressure compressed air ensures rapid pressure build-up in the initial startup phase; after the engine warms up, the exhaust pulse can replace the independent high-pressure air pump to achieve stable injection.

[0058] After step S5, it may also include: S6. Based on the real-time status parameters of the engine, determine in real time whether the current operating condition of the rotary engine is cold start condition, warm-up transition condition, or normal operating condition. Based on the real-time determined current operating condition, when the engine operating condition changes, control mode switching valve 17, compression side intake valve, and exhaust side intake valve switch from the control mode of the previous operating condition to the control mode corresponding to the current operating condition.

[0059] In this embodiment, once the system has stabilized in the warm-up / normal operation state, the compression-side intake pipe 15 exits the main air supply mode, retaining only the exhaust-side pulse air supply. The engine then continues into the warm-up and normal operation phases. If necessary, if the exhaust pulse pressure continues to drop below the backoff threshold and the casing temperature decreases significantly, the control unit can back the system from the normal operation state to a transition state, and if necessary, further back to the compression-side air supply mode to ensure that the nozzle peripheral air passages always receive sufficient high-pressure atomized gas.

[0060] Correspondingly, step S1 is followed by: S101. Identify the target combustion chamber currently located in the injection window based on the eccentric shaft angle and the rotor engine speed.

[0061] Correspondingly, step S2 includes: S21. Based on the eccentric shaft angle, engine speed, and the time required for compressed gas to be delivered from the compression-side air intake to the gas-assisted atomizing nozzle 19, determine the first air intake time when the target combustion chamber passes the compression-side air intake and is within the effective pressure range of the compression stroke. The first air intake time is earlier than the injection time of the target combustion chamber, and the phase interval between the first air intake time and the injection time satisfies the time requirement for the compressed high-pressure gas to reach the gas-assisted atomizing nozzle.

[0062] S22. During the first intake time, the ECU opens the compression side intake valve on the compression side intake line 15, allowing the high-pressure compressed gas formed in the target combustion chamber during its own compression stroke to enter the compression side intake line 15 and finally be delivered to the gas-assisted atomizing nozzle 19 for auxiliary atomization during subsequent fuel injection.

[0063] Specifically, the rotor has three profiles, which form combustion chambers with the housing wall and cylinder head wall, respectively. Because these profiles are different and rotate with the rotor, the combustion chambers are not three fixed, independent chambers. Specifically, the three working profiles or sections in the engine that sequentially rotate to the positions of the compression-side air intake and the gas-assisted atomizing nozzle 19 on the housing wall, all within the compression zone, are sequentially numbered A, B, and C. Combustion chambers A, B, and C alternately pass the gas-assisted atomizing nozzle 19 and the compression-side air intake, and correspondingly, they also alternately pass the exhaust-side air intake, so the correspondence changes periodically. Based on the aforementioned definitions of combustion chambers A, B, and C, when a combustion chamber reaches the position of the gas-assisted atomizing nozzle 19, it is in the compression stroke, and the ECU typically triggers injection according to the set injection parameters. As the rotor rotates, different combustion chambers sequentially pass the nozzle positions, and the ECU periodically triggers injection according to a preset phase relationship, thereby achieving continuous fuel supply to each combustion chamber.

[0064] Based on this, after completing the operating condition identification, the ECU identifies the target combustion chamber currently located at the injection window (passing through the nozzle) according to the eccentric shaft angle. This indicates that the target combustion chamber is any one of combustion chambers A, B, or C. During implementation, for a single-rotor three-face structure, the injection windows WA, WB, and WC of the three combustion chambers A, B, and C relative to the nozzle installation position can be pre-calibrated. When the eccentric shaft angle ∈ WA, combustion chamber A is the target combustion chamber currently requiring injection; similarly, when the eccentric shaft angle ∈ WB, combustion chamber B is the target combustion chamber; and when the eccentric shaft angle ∈ WC, combustion chamber C is the current target combustion chamber.

[0065] Then, in the cold start state, the high-pressure air on the compression side is preferably taken from the target combustion chamber that will pass through the nozzle itself. Since the compression side air intake is located on the wall of a fixed compression zone upstream of the nozzle installation position, the ECU can determine the moment when the target combustion chamber sweeps through the air intake and is within the effective window of the compression stroke based on the eccentric shaft angle, the rotor engine speed, and the time required for the high-pressure air to be delivered from the compression side air intake to the nozzle. This moment is taken as the first air intake time, and the compression side air intake valve is opened at the first air intake time, so that the high-pressure air formed by the compression of the target combustion chamber flows through the compression side air intake to the compression side air intake pipeline 15, and after passing through the mode switching component and the intake manifold 18, it is sent to the outer annular air passage of the gas-assisted atomizing nozzle 19. Thus, in the compression side air supply mode, the air intake and subsequent injection belong to the same target combustion chamber.

[0066] After the ECU determines the first air intake time, it can continue to make the first air intake time earlier than the injection time of the target combustion chamber based on the injection time set by the engine. The time interval between the first air intake time and the injection time meets the time requirement for the compressed high-pressure air to reach the nozzle. This ensures that the extracted compressed air source can belong to the high-pressure air formed under the compression stroke of the target combustion chamber itself under different speeds, loads or operating conditions.

[0067] More preferably, the auxiliary atomizing gas source used when fuel is injected into the target combustion chamber is the high-pressure air generated by the compression stroke of the combustion chamber itself. In this embodiment, a strategy of completing air intake before injection is prioritized. In a specific implementation, the fixed air intake port on the compression side is arranged upstream of the nozzle installation position, so that the same target combustion chamber first passes through the compression side air intake port and then moves to the nozzle position during subsequent rotation. Therefore, based on the eccentric shaft angle, the rotor engine speed, and the time required for compressed high-pressure gas to be delivered from the compression side air intake port to the gas-assisted atomizing nozzle, the first air intake time when the target combustion chamber passes through the compression side air intake port and is within the effective pressure range of the compression stroke can be determined. Based on the injection timing set by the engine, the first air intake time should be earlier than the injection time under the same compression stroke, thus satisfying the "air intake first, injection later" requirement in terms of timing. For example, the ECU uses the eccentric shaft angle when the target combustion chamber passes through the compression side air intake port as the first air intake angle and the eccentric shaft angle when the target combustion chamber enters the injection window as the injection angle, and converts the phase difference between the two into an interval time based on the engine speed. This interval should be no less than the delivery time and pressure build-up time (gas intake time) required for compressed air to travel from the compressed side intake port through the compressed side intake pipeline to the annular air passage surrounding the gas-assisted atomizing nozzle. This satisfies the timing requirement of "complete gas intake first, then start injection," thereby ensuring that the fuel is fully atomized before being injected into the combustion chamber, improving the uniformity of the air-fuel mixture, and thus enhancing the combustion efficiency during cold starts.

[0068] Furthermore, this control strategy relies on the provided system, and its structural layout achieves a "take-in-gas-then-inject" time sequence. Therefore, it can retain the original nozzle's injection pressure, injection quantity, injection timing, and other injection parameters. Structurally, it matches the timing requirements, realizing a take-in-gas matching control system where compressed air passes through the nozzle, fuel atomization is injected later, and combustion is completed in the same combustion chamber. This has significant effects and can also avoid modifying the nozzle design, reducing modification costs and structural complexity, and enabling direct application on existing engines.

[0069] In some alternative embodiments, the position between the compression side intake port and the nozzle can be adjusted. The injection timing and the first intake time can be set by the ECU according to the eccentric shaft angle and rotation speed. That is, according to the first intake time, the injection timing at which the target combustion chamber begins to perform injection is set, and the gas-assisted atomizing nozzle 19 is controlled to inject fuel at the injection timing that lags behind the first intake time and falls into the injection window of the target combustion chamber. Then, the gas-assisted atomizing nozzle 19 is controlled to inject fuel at this injection timing to achieve the time sequence of "take in the gas first, then inject".

[0070] Correspondingly, when taking air from the exhaust side in step S3 and / or step S4, the specific steps include: S31. Based on the injection time of the target combustion chamber, the delivery time from the exhaust side air intake to the gas-assisted atomizing nozzle 19, the phase difference between the combustion chamber currently in the exhaust stroke and the target combustion chamber, and the pressure amplitude of the current exhaust pulse gas, determine the second air intake time that is compatible with the injection requirements of the target combustion chamber in terms of arrival time and pressure amplitude. S32, control the exhaust side air intake valve on the exhaust side air intake pipeline 3 to open during the second air intake time.

[0071] The ECU does not directly select a fixed combustion chamber as the air source. Instead, it uses the injection time of the target combustion chamber as a reference and monitors the pressure amplitude of the exhaust pulse gas currently within the exhaust stroke (at a fixed exhaust port or at the exhaust-side air intake port on the exhaust passage 10) through the exhaust pulse pressure sensor. It also calculates the time when the exhaust pulse arrives at the nozzle and selects a second air intake time that best suits the pressure amplitude and arrival time of the exhaust pulse gas to meet the injection requirements of the target combustion chamber currently in the compression stroke or matches the injection parameters. This ensures that the second air intake time corresponds to the injection time of the target combustion chamber. During the second air intake time, the exhaust-side air intake valve is opened, allowing the phase-matched high-pressure exhaust pulse to enter the exhaust-side pipeline. After passing through the check valve 9, the buffer pressure regulating component, and the mode switching valve 17, the pulse is sent to the annular air passage surrounding the gas-assisted atomizing nozzle 19, which is connected to the target combustion chamber.

[0072] Therefore, by calculating the intake and injection times using the eccentric shaft angle and rotor rotation phase, and by utilizing the fixed rotation phase of the rotary engine and the timing matching characteristics of the air sources on the compression and exhaust sides, the injection time of the high-pressure air source and the target combustion chamber can be better matched, so that the fuel can be fully atomized when injected into the combustion chamber.

[0073] It should be noted that, for the method embodiments, the embodiments of this application are not limited to the described order of actions, because according to the embodiments of this application, some steps may be performed in other orders or simultaneously.

[0074] In summary, the technical solutions provided by one or more embodiments of the present invention use the same gas-assisted atomizing nozzle 19 as the injection actuator, and switch between the high-pressure gas source on the compression side and the high-pressure pulse gas source on the exhaust side based on the identification result of the current engine operating condition. The control unit mainly identifies the target combustion chamber based on the signal of the eccentric shaft angle sensor 13 and in combination with the engine speed. Under cold start conditions, the control unit opens the compression side intake valve when the current target combustion chamber is in the compression stroke intake window, allowing the compressed high-pressure gas of the target combustion chamber to enter the annular gas passage around the nozzle; under warm-up or normal operation conditions, the control unit extracts the phase-matched exhaust high-pressure pulse within the effective time window on the exhaust side and sends it into the annular gas passage around the nozzle. During cold start, the high-pressure gas on the compression side is used to ensure rapid pressure build-up in the initial stage of start-up; after the engine warms up, the exhaust pulse is used to replace the independent high-pressure gas pump to achieve stable injection.

[0075] 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.

[0076] It should also be noted that, in this document, the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, 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, nor should they be construed as indicating or implying relative importance. Moreover, the term "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements, but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device.

Claims

1. An air-assisted injection system based on internal gas of a rotary engine, comprising an engine body, wherein an engine rotor is disposed inside the engine body, and a gas-assisted atomizing nozzle, an air inlet, and an exhaust port are disposed on the wall of the engine body and communicate with the inner cavity of the engine body, wherein the gas-assisted atomizing nozzle is connected to a fuel supply pipeline; characterized in that, Also includes: A compression-side air intake is located on the wall surface of the main body at a position corresponding to the compression zone of the inner cavity; The exhaust side air intake is located at a position that is directly or indirectly connected to the exhaust area of ​​the inner cavity; A compression-side air intake line is connected to the compression-side air intake port and is used to extract compressed high-pressure gas during the compression stroke. An exhaust-side air intake pipeline is connected to the exhaust-side air intake port and is used to extract exhaust pulse gas during the exhaust stroke. A mode switching valve is used to switch between a first position and a second position. When the mode switching valve is in the first position, the compression side gas intake line is connected to the gas-assisted atomizing nozzle to deliver the compressed high-pressure gas to the gas-assisted atomizing nozzle to achieve compressed gas-assisted fuel atomization. When the mode switching valve is in the second position, the exhaust side intake pipe is connected to the gas-assisted atomizing nozzle to deliver the exhaust pulse gas to the gas-assisted atomizing nozzle, thereby achieving exhaust-assisted fuel atomization.

2. The air-assisted injection system based on internal gas of a rotary engine according to claim 1, characterized in that, Along the rotation direction of the engine rotor, the compression-side air intake is located in front of the gas-assisted atomizing nozzle; and / or, The exhaust port is used to communicate with the exhaust duct, and the exhaust side air intake is located on the exhaust duct.

3. The air-assisted injection system based on internal gas of a rotary engine according to claim 1, characterized in that, The compression-side air intake pipeline and the exhaust-side air intake pipeline are respectively equipped with an air intake valve, a check valve, and a pressure stabilizing tank, and the pressure stabilizing tank is connected to the mode switching valve.

4. The air-assisted injection system based on internal gas of a rotary engine according to claim 1, characterized in that, The system also includes a data acquisition unit, which includes at least one of an eccentric shaft angle sensor, an engine speed sensor, a housing temperature sensor, a nozzle air-side pressure sensor, an exhaust pulse pressure sensor, and a compressed air pressure sensor. The exhaust pulse pressure sensor is located on the exhaust side air intake pipe, and the compressed air pressure sensor is located on the compressed side air intake pipe.

5. An air-assisted injection system based on internal gas of a rotary engine according to claim 4, characterized in that, The system also includes: The electronic control unit is connected to each sensor, each valve on the pipeline, and the mode switching valve. The electronic control unit is used for: The system receives status parameters collected by various sensors, determines the current operating condition of the rotary engine and the target combustion chamber under compression stroke, controls the valves on each pipeline to different opening degrees, and controls the mode switching valve to switch between the first position and the second position.

6. An air-assisted injection method based on internal gas of a rotary engine, characterized in that, Relying on an air-assisted injection system based on the internal gas of a rotary engine as described in any one of claims 1-5, the method is applied to an electronic control unit and includes: Obtain the current operating condition of the rotary engine; the current operating condition includes any one of the following: cold start condition, warm-up transition condition, and normal operation condition; In cold start condition, the control mode switching valve is in the first position, the compression side air intake valve on the compression side air intake line is open, and the exhaust side air intake valve on the exhaust side air intake line is closed, so as to deliver compressed high-pressure gas to the gas-assisted atomizing nozzle. During the warm-up transition, the control mode switching valve is in the first position, the exhaust side air intake valve on the exhaust side air intake pipeline is opened, and the compression side air intake valve on the compression side air intake pipeline is closed after a preset time, so as to pre-deliver the exhaust pulse gas to the mode switching valve. Under normal operating conditions, the control mode switching valve is switched to the second position, the compression side air intake valve on the compression side air intake line is closed, and the exhaust side air intake valve on the exhaust side air intake line is opened to deliver the exhaust pulse gas to the gas-assisted atomizing nozzle. Based on the current operating conditions, control the gas-assisted atomizing nozzle to inject fuel, so that the fuel is assisted in atomization by the compressed high-pressure gas or the exhaust pulse gas corresponding to the current operating conditions during the injection process.

7. The air-assisted injection method based on internal gas of a rotary engine according to claim 6, characterized in that, The process of obtaining the current operating condition of the rotary engine then includes: Based on the eccentric shaft angle and the rotor engine speed, identify the target combustion chamber currently located at the injection window; Under the cold start condition, controlling the opening of the compression side air intake valve on the compression side air intake pipeline includes: Based on the eccentric shaft angle, the rotor engine speed, and the time required for compressed air to be delivered from the compression side intake port to the gas-assisted atomizing nozzle, the first intake time when the target combustion chamber passes through the compression side intake port and is within the effective pressure range of the compression stroke is determined. During the first gas intake time, the compression side intake valve on the compression side intake pipeline is opened, so that the high-pressure compressed gas formed in the target combustion chamber during its own compression stroke can assist in atomizing the fuel injected into the target combustion chamber.

8. The air-assisted injection method based on internal gas of a rotary engine according to claim 7, characterized in that, The step of opening the compression-side air intake valve on the compression-side air intake pipeline during the first air intake time includes: The gas intake duration is determined based on the time required for compressed high-pressure gas to be delivered from the compression side gas intake port to the gas-assisted atomizing nozzle and the nozzle pressure build-up time. Based on the injection time of the target combustion chamber, the first gas intake time is controlled to be earlier than the injection time, and the time interval between the first gas intake time and the injection time is not less than the gas intake duration, so as to inject fuel after compressed gas assisted atomization into the target combustion chamber.

9. An air-assisted injection method based on internal gas of a rotary engine according to claim 7 or 8, characterized in that, Controlling the opening of the exhaust-side intake valve on the exhaust-side intake pipeline includes: Based on the injection time of the target combustion chamber, the delivery time from the exhaust side air intake to the gas-assisted atomizing nozzle, the phase difference between the combustion chamber currently in the exhaust stroke and the target combustion chamber, and the pressure amplitude of the current exhaust pulse gas, a second air intake time is determined that both the arrival timing and pressure amplitude are adapted to the injection requirements of the target combustion chamber. The exhaust-side air intake valve on the exhaust-side air intake pipeline is opened during the second air intake time.

10. The air-assisted injection method based on internal gas of a rotary engine according to claim 6, characterized in that, Under the aforementioned warm-up transition condition, the exhaust-side air intake valve on the exhaust-side air intake pipeline is opened, prior to which the following steps are included: Take the exhaust pulse gas and use it as the atomizing gas source at at least one injection moment; Obtain the nozzle air-side pressure and exhaust pulse intensity at the corresponding injection moment; When the nozzle air-side pressure and the exhaust pulse pressure meet the atomization conditions, the exhaust-side air intake valve on the exhaust-side air intake pipeline is controlled to be in the open state.

Images