An air supply system and control method for a compression ignition pre-combustion chamber of an engine

Abstract

The present invention discloses an air supply system and control method for a compression ignition pre-combustion chamber of an engine, comprising: an engine and an air supply pipeline, wherein the engine is provided with at least one compression ignition pre-combustion chamber and a main combustion chamber connected to each other, wherein the compression ignition pre-combustion chamber is provided with a scavenging air intake port and a scavenging air exhaust port; the air supply pipeline comprises a mixing chamber, a compressor, a distribution chamber, a pressure control valve, and a circulating air release valve, wherein the mixing chamber, the compressor, the distribution chamber, and the circulating air release valve are connected in a closed loop, wherein the distribution chamber is connected to the scavenging air intake port, wherein the mixing chamber is connected with a mixed gas fuel nozzle and an air intake pipe, wherein the pressure control valve is connected to the scavenging air exhaust port, and a heating component is provided between each of the scavenging air intake ports and the distribution chamber. The air supply system of the present invention realizes the mixing of fuel and air, and at the same time has the capability of managing the pressure, temperature, and ventilation of the mixed gas, so as to ensure that the mixed gas can be reliably compressed and ignited after entering the compression ignition pre-combustion chamber.

Description

Technical Field

[0001] The invention relates to the technical field of engine combustion, and in particular to an air supply system and a control method for a compression ignition pre-combustion chamber of an engine. Background Art

[0002] In the research of lean combustion, pre-chamber combustion technology has received extensive attention. This combustion technology first ignites the mixture in the pre-chamber that can be easily ignited by a spark plug, and then burns the mixture in the pre-chamber to form a high-temperature, high-pressure combustion mixture, which is introduced into the main combustion chamber and ignites the lean mixture in the main combustion chamber. After that, the lean mixture in the main combustion chamber burns rapidly. Pre-chamber combustion technology can effectively solve combustion problems such as difficult ignition under lean combustion conditions, slow combustion speed, and large combustion cycle changes. The mixture in the pre-chamber can be ignited by ignition or compression ignition. Ignition generally uses spark plugs or electric heating devices to ignite the pre-mixed gas, while compression ignition uses compressed mixture to make the mixture reach the auto-ignition temperature and ignite. Compression ignition requires the formation of a compressible enclosed space in the pre-chamber to ensure that the mixture inside it can be compressed, and it is also necessary to provide it with a mixture that can be compressed.

[0003] The key to compression ignition pre-chamber combustion technology is to form a stable and compressible ignition mixture in the pre-chamber. To this end, it is necessary to provide an air supply and exhaust structure in the pre-chamber, and an auxiliary air supply system. However, the current pre-chamber air supply system is only suitable for ignition pre-chamber systems, which only realizes the supply and mixing of fuel and air, and cannot manage the pressure, temperature and ventilation of the fuel and air mixture. Summary of the invention

[0004] The object of the present invention is to provide an air supply system and control method for a compression ignition pre-combustion chamber of an engine, so as to solve one or more technical problems existing in the prior art and at least provide a beneficial choice or create conditions.

[0005] The technical solutions adopted to solve the above technical problems are:

[0006] First, the present invention provides an air supply system for a compression ignition pre-combustion chamber of an engine, comprising: an engine and an air supply pipeline, the engine is provided with at least one compression ignition pre-combustion chamber and a main combustion chamber connected to each other, the compression ignition pre-combustion chamber is provided with a scavenging air inlet and a scavenging air exhaust port; the air supply pipeline comprises a mixing chamber, a compressor, a distribution chamber, a pressure control valve, and a circulating air release valve, the mixing chamber, the compressor, the distribution chamber and the circulating air release valve are connected in a closed loop, the distribution chamber is connected to the scavenging air inlet, the mixing chamber is connected to a mixture fuel nozzle and an air intake pipe, the pressure control valve is connected to the scavenging air exhaust port, and a heating component is provided between each of the scavenging air inlet and the distribution chamber.

[0007] The beneficial effects of the gas supply system of the present invention are:

[0008] The air supply system of the present invention achieves mixing of fuel and air, and at the same time has the capability of managing the pressure, temperature and ventilation of the mixed gas, thereby ensuring that the mixed gas can be reliably compressed and ignited after entering the compression ignition pre-combustion chamber.

[0009] As a further improvement of the above technical solution, the air intake pipe is provided with an air flow meter and a heat exchanger.

[0010] The air flow meter is used to measure the air flow rate sucked into the mixing chamber to determine the fuel supply amount of the mixed gas fuel nozzle, while the heat exchanger is used to heat the air sucked into the air supply system, reduce the power required by the compressor and adapt to different working conditions.

[0011] As a further improvement of the above technical solution, the engine also includes an intake duct connected to the main combustion chamber, the intake duct is provided with a return air port, and the pressure control valve is connected between the scavenging exhaust port and the return air port.

[0012] The intake duct in this scheme is the channel for air input when the engine is running. After the mixture entering the compression ignition pre-combustion chamber is compression ignited, part of it enters the main combustion chamber and ignites the fuel-air mixture in the main combustion chamber, and part of it enters the intake duct through the return air port and is then sucked into the main combustion chamber of the engine, so that the fuel is used more fully and unburned fuel is prevented from being discharged directly into the atmosphere.

[0013] As a further improvement of the above technical solution, a collecting chamber is provided between the pressure control valve and the scavenging exhaust port.

[0014] The collecting chamber is used to collect all the combustion-completed mixed gases discharged from the compression ignition pre-combustion chambers, and the pressure in the compression ignition pre-combustion chambers and the mixed gas pressure in the distribution chamber are controlled by the pressure control valve during the air supply phase.

[0015] As a further improvement of the above technical solution, an air filter is provided at the inlet end of the air intake duct, and the air intake duct is provided with an air intake port connected to the air intake pipe, and the air intake port and the air return port are both located downstream of the air filter.

[0016] The air filter filters the air flowing into the intake duct. While filtering the air entering the main combustion chamber, it can also ensure that the air entering the air supply system is clean air filtered by the air filter, so that the air supply system does not need to be equipped with additional filters.

[0017] As a further improvement of the above technical solution, the air intake pipe is provided with a one-way valve, which is used to prevent the air in the air supply system from flowing back into the air intake passage.

[0018] As a further improvement of the above technical solution, a scavenging air intake pipe is connected between the scavenging air intake port and the distribution chamber, the heating assembly is an induction heating coil wrapped around the outer wall of the scavenging air intake pipe, and the scavenging air intake port is provided with a second temperature sensor. The present invention utilizes an electromagnetic induction heating pipeline, which has a fast heating speed and a compact structure, and the second temperature sensor is used to detect the temperature of the mixed gas entering the compression ignition pre-combustion chamber.

[0019] As a further improvement of the above technical solution, the distribution chamber is provided with a pressure sensor and a first temperature sensor, which are used to monitor the pressure and temperature of the mixed gas inside the distribution chamber.

[0020] As a further improvement of the above technical solution, it also includes a control unit, which is used to detect the working state of the engine, the flow of the air intake pipe, the pressure and temperature of the distribution chamber, and the temperature of the scavenging air intake port, so as to control the compression power of the compressor, the injection of the mixture fuel nozzle, the heating component, the circulation bleed valve and the opening of the pressure control valve.

[0021] The present invention also provides an air supply control method for a compression ignition pre-combustion chamber of an engine, comprising:

[0022] When the engine is in a steady-state condition, the outside air enters the mixing chamber through the air intake pipe under the action of the pressure difference. According to the air flow rate of the air intake pipe, the mixed gas fuel nozzle is controlled to let the corresponding target fuel enter the mixing chamber. The compressor delivers the compressed mixed gas to the distribution chamber, and then enters each compression ignition pre-combustion chamber in sequence through different pipelines between the compression ignition pre-combustion chamber and the distribution chamber. At the same time, the temperature of the mixed gas entering each compression ignition pre-combustion chamber is heated by the heating component. The pressure of the mixed gas in the distribution chamber is controlled by the opening of the pressure control valve. The amount of the circulating mixed gas is controlled by controlling the opening of the circulating air release valve and the compression power of the compressor, so as to achieve the purpose of controlling the temperature of the mixed gas in the distribution chamber.

[0023] When the engine is in acceleration condition, the compression power of the compressor is controlled to increase on the basis of steady-state condition, the circulating air release valve is controlled to remain closed, so that the air intake volume of the air intake pipe increases rapidly, the mixed gas fuel nozzle is controlled to allow the corresponding target fuel to enter the mixing chamber, and the opening of the pressure control valve is controlled to ensure that the mixed gas pressure in the distribution chamber meets the target;

[0024] When the engine is in a rapid deceleration condition, the compression power of the compressor is controlled to decrease on the basis of the steady-state condition, and the circulating air bleed valve is controlled to remain fully open to rapidly reduce the air intake volume of the air intake pipe. The mixture fuel nozzle is controlled to allow the corresponding target fuel to enter the mixing chamber, and the opening of the pressure control valve is controlled to ensure that the mixture pressure in the distribution chamber meets the target.

[0025] The present invention proposes an air supply control method for a compression ignition pre-combustion chamber, further clarifies the operation method of the air supply system of the compression ignition pre-combustion chamber, and accurately and reliably realizes the temperature, pressure, composition and flow management of the compression ignition pre-combustion chamber intake air. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described below in conjunction with the accompanying drawings and embodiments;

[0027] Figure 1 The present invention provides an air supply system for a compression ignition pre-combustion chamber of an engine, and a schematic structural diagram of one embodiment thereof. DETAILED DESCRIPTION

[0028] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0029] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0030] In the description of the present invention, if there are words such as "several", it means one or more, "more" means more than two, greater than, less than, exceed, etc. are understood as not including the number, and above, below, within, etc. are understood as including the number.

[0031] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0032] Reference Figure 1 The air supply system of the engine compression ignition pre-combustion chamber of the present invention is implemented as follows:

[0033] like Figure 1 As shown, the air supply system of this embodiment includes an engine and an air supply pipeline.

[0034] The engine is a reciprocating piston engine, and its structure and form are consistent with those of existing conventional engines not described herein, wherein the structures and forms of components such as the cylinder head, cylinder block, piston, connecting rod, crankshaft, air filter, intake duct 210, intake valve, compression ignition pre-combustion chamber 100, main fuel nozzle, exhaust duct and exhaust valve are similar to those of existing conventional internal combustion engines not described herein, and at least one cylinder and at least one compression ignition pre-combustion chamber 100 are provided on the cylinder block of the engine, and a compression ignition pre-combustion chamber 100 is provided on the cylinder head corresponding to each cylinder, and the compression ignition pre-combustion chamber 100 is provided with a scavenging air intake port 110 and a scavenging air exhaust port 120, and the scavenging air intake port 110 and the scavenging air exhaust port 120 are respectively used for introducing a mixed gas and discharging exhaust gas after combustion.

[0035] The space defined by the cylinder head, cylinder body, piston, main fuel nozzle, intake valve and exhaust valve is the main combustion chamber 200, which is used to provide a place for the combustion process of the fuel and air mixture. The compression ignition pre-combustion chamber 100 is an ignition device corresponding to the fuel-air mixture in the main combustion chamber 200.

[0036] In this embodiment, an air filter 212 is installed at the inlet of the air intake duct 210 , and the air filter 212 filters the air flowing into the air intake duct 210 .

[0037] The air supply system of this embodiment also includes a control unit 900, which adopts a microcomputer. The microcomputer is a small electronic computer composed of a large-scale integrated circuit. It is based on a microprocessor and is equipped with an internal memory, an input and output I / O interface circuit and corresponding auxiliary circuits to form a bare machine. Its structure and form are similar to the existing conventional microcomputers used in automotive electronic control systems that are not described in this article.

[0038] The air supply pipeline of this embodiment includes a mixing chamber 300, a compressor 400, a distribution chamber 500, a pressure control valve 600, a circulating air release valve 700, an air flow meter 321, a heat exchanger 322, a collecting chamber 800, a one-way valve 323, a heating assembly, a mixed gas fuel nozzle 310 and an air intake pipe 320.

[0039] The compressor 400 is a driven fluid machine that boosts low-pressure gas to high-pressure gas. It is provided with an inlet and an outlet for introducing low-pressure gas and discharging high-pressure gas. Its structure and form are similar to those of existing conventional compressors not described in this article. The compressor 400 is connected to an electric motor 410, which drives the compressor 400 to compress the gas, thereby increasing the pressure and temperature of the gas.

[0040] The one-way valve 323 is a directional control valve that allows airflow to flow in only one direction but not in the reverse direction. Its structure and form are similar to existing conventional one-way valves that are not described herein.

[0041] The heat exchanger 322 is a device that transfers part of the heat of the hot fluid to the cold fluid. Its structure and form are similar to the existing conventional heat exchanger not described in this article. It has four fluid inlets and outlets, namely, a cold fluid inlet, a cold fluid outlet, a hot fluid inlet, and a hot fluid outlet.

[0042] The mixing chamber 300, the distribution chamber 500 and the collecting chamber 800 are all common objects that are sealed and isolated from the outside and are hollow inside. At the same time, a plurality of inlets and outlets for fluid entry and exit are provided on the surface. The mixing chamber 300 is provided with at least four fluid inlets and outlets, including an air intake inlet, a mixed gas outlet, a circulating mixed gas inlet and a first fuel inlet. The distribution chamber 500 is provided with at least three fluid inlets and outlets, including a mixed gas inlet, a circulating mixed gas outlet and a first mixed gas outlet. The collecting chamber 800 is provided with at least two fluid inlets and outlets, including a mixed gas outlet and a first mixed gas inlet.

[0043] The mixture fuel nozzle 310 is a device for spraying fuel (liquid or gas) into a specific space, and its structure and form are similar to the existing conventional fuel nozzle which is not described herein.

[0044] The pressure control valve 600 and the circulating air release valve 700 are both electromagnetically controlled industrial equipment, which are basic automation components used to control fluids and are used in industrial control systems to adjust the direction, flow, speed and other parameters of the medium. Their structure and form are similar to existing conventional solenoid valves not described in this article.

[0045] The mixing chamber 300 , the compressor 400 , the distribution chamber 500 and the circulating air release valve 700 are connected via a pipeline closed loop, and the air intake pipe 320 and the mixed gas fuel nozzle 310 are respectively connected to the mixing chamber 300 .

[0046] For the air intake of the air supply system of this embodiment, the air intake duct 210 is provided with an air intake port 213, and the air intake pipe 320 is connected to the air intake port 213, and the air intake port 213 is located downstream of the air filter 212. When the air entering the main combustion chamber 200 is filtered, it can also be ensured that the air entering the air supply system is clean air filtered by the air filter 212, so that the air supply system does not need to be provided with an additional filter.

[0047] In other embodiments, the air extraction pipe 320 may be directly connected to the outside.

[0048] The one-way valve 323 and the heat exchanger 322 of this embodiment are installed on the air intake pipe 320. The one-way valve 323 is used to prevent the air in the air supply system from flowing back into the air intake duct 210, while the heat exchanger 322 is used to heat the air inhaled by the air supply system, reduce the power required by the compressor 400, and adapt to different working conditions.

[0049] Among them, the cold fluid inlet of the heat exchanger 322 is connected to the air intake port 213, and the cold fluid outlet of the heat exchanger 322 is connected to the air inlet of the mixing chamber through a pipeline, and the heated air is introduced into the mixing chamber 300. The hot fluid inlet and outlet of the heat exchanger 322 are respectively connected to the hot fluid medium, which can be the engine's cooling water, exhaust gas, etc. It is preferred to use a shell and tube heat exchanger in the partition type heat exchanger. The hot fluid can be the engine cooling water or the engine exhaust. It is preferred to use engine cooling water, which is easy to arrange, has a moderate temperature, and has a high heat transfer efficiency.

[0050] Furthermore, the air intake pipe 320 is provided with an air flow meter 321, which is used to measure the air flow rate sucked into the mixing chamber 300 and transmit the flow signal to the microcomputer for calculating the fuel supply amount. According to its structural type, it can adopt blade (wing plate) type, core type, hot wire type, hot film type, Karman vortex type and other types.

[0051] The mixing chamber 300 provides a place for fuel and air to mix, and also collects the mixed gas that is circulated to the inlet of the compressor 400 by the circulating bleed valve 700.

[0052] The mixed gas fuel nozzle 310 is used to provide fuel to the mixed gas in the mixing chamber 300. Preferably, an electromagnetic fuel nozzle is used, which receives the injection pulse signal sent by the microcomputer and accurately controls the fuel injection amount.

[0053] The fuel injected by the mixture fuel nozzle 310 is kept consistent with the fuel injected by the main fuel nozzle; further, a fuel nozzle for injecting low autoignition temperature fuel, such as dimethyl ether, methanol, etc., can be installed on the mixing chamber 300 to solve the cold start problem.

[0054] The compressor 400 is used to compress the mixed gas to increase the gas pressure and temperature, and deliver the compressed mixed gas into the distribution chamber 500 .

[0055] The distribution chamber 500 is connected to the scavenging air intake port 110 . The distribution chamber 500 distributes the compressed fuel-air mixture to different compression ignition pre-combustion chambers 100 , and can also reintroduce the mixture into the inlet of the compressor 400 through the circulating bleed valve 700 .

[0056] A pressure sensor 510 and a first temperature sensor 520 are installed on the distribution chamber 500 to ensure that the microcomputer can sense the pressure and temperature of the mixed gas in the distribution chamber 500 .

[0057] The circulating air bleed valve 700 can reintroduce the mixed gas in the distribution chamber 500 into the inlet of the compressor 400, which can increase the outlet temperature of the compressor 400 on the one hand, and quickly reduce the pressure of the distribution chamber 500 on the other hand; preferably, the circulating air bleed valve 700 is an electromagnetic control valve, and the microcomputer outputs a control signal to control the opening of the circulating air bleed valve 700, so as to achieve the purpose of controlling the temperature and pressure of the mixed gas in the distribution chamber 500.

[0058] The heating component is arranged between each scavenging air inlet port 110 and the distribution chamber 500. Specifically, a scavenging air inlet pipe 111 is connected between the scavenging air inlet port 110 and the distribution chamber 500. The heating component is an induction heating coil 113 wrapped around the outer wall of the scavenging air inlet pipe 111. In other embodiments, other heating devices can also be used to heat the pipeline. Preferably, electromagnetic induction heating pipeline is used, which has a fast heating speed and a compact structure.

[0059] The induction heating coil 113 is a device that utilizes electromagnetic induction to heat electrical metals. It generates eddy currents in the metal, causing the temperature of the metal to rise due to electrical resistance.

[0060] A second temperature sensor 112 is provided on one of the pipelines between the distribution chamber 500 and the compression ignition pre-combustion chamber 100, near the scavenging air intake port 110 of the compression ignition pre-combustion chamber 100, for the microcomputer to monitor the temperature of the mixed gas at the scavenging air intake port 110, and control the output of the induction heating coil 113 accordingly, so as to control the temperature of the mixed gas entering the compression ignition pre-combustion chamber 100.

[0061] For the exhaust of the compression ignition pre-combustion chamber 100 , the intake duct 210 of this embodiment is provided with a return air port 211 , and the collecting chamber 800 and the pressure control valve 600 are connected in sequence between the scavenging exhaust port 120 and the return air port 211 , wherein the air intake port 213 and the return air port 211 are both arranged downstream of the air filter 212 .

[0062] The collecting chamber 800 is used to collect all the combustion mixtures discharged from the compression ignition pre-combustion chamber 100, and the pressure in the compression ignition pre-combustion chamber 100 and the pressure of the mixture in the distribution chamber 500 during the air supply stage are controlled by the pressure control valve 600.

[0063] In this embodiment, after the mixture entering the compression ignition pre-combustion chamber 100 is compression ignited, part of it enters the main combustion chamber 200 and ignites the fuel-air mixture in the main combustion chamber 200, and part of it enters the intake duct 210 through the return air port, and is then sucked into the main combustion chamber 200 of the engine, so that the fuel is used more fully and unburned fuel is prevented from being discharged directly into the atmosphere.

[0064] In this embodiment, the pressure in the compression ignition pre-combustion chamber 100 and the pressure of the mixed gas in the distribution chamber 500 during the air supply stage are controlled by the pressure control valve 600. The pressure control valve 600 is an electromagnetic control valve. The microcomputer outputs a control signal to control the opening of the pressure control valve 600, so as to achieve the purpose of controlling the pressure of the mixed gas in the distribution chamber 500 and the pressure in the compression ignition pre-combustion chamber 100.

[0065] The air flow meter 321, the pressure sensor 510, the first temperature sensor 520 and the second temperature sensor 112 all refer to detection devices that can sense the measured information and convert the sensed information into electrical signals or other required forms of information output according to certain rules to meet the requirements of information transmission, processing, storage, display, recording and control.

[0066] The microcomputer is connected to the air flow meter 321, the pressure sensor 510, the first temperature sensor 520 and the second temperature sensor 112 through signal lines. The microcomputer collects data and signals from the sensors. The microcomputer is connected to actuators such as the mixture fuel nozzle 310, the motor 410, the circulating bleed valve 700, the pressure control valve 600 and the induction heating coil 113 through signal lines. The microcomputer outputs a control model to control the action of the actuator.

[0067] The present invention also provides a method for controlling the air supply, wherein the engine operates in a conventional four-stroke engine operation mode not described herein and outputs power externally, and the specific method is as follows:

[0068] When the engine is in a steady-state condition, the motor 410 drives the compressor 400 to rotate, and the compressor 400 compresses the inlet mixed gas, and the pressure and temperature rise; the pressure of the inlet mixed gas of the compressor 400 is reduced after being sucked away, and under the action of the pressure difference, the outside air first enters the intake duct 210, and enters the mixing chamber 300 through the air filter 212, the air intake port 213, the one-way valve 323, the air flow meter 321 and the heat exchanger 322; the one-way valve 323 automatically opens under the action of the gas pressure difference, the air flow meter 321 measures the air flow, and the hot fluid cooling water in the heat exchanger 322 heats the air to increase its temperature; the microcomputer determines the mixed gas through calculation and processing based on the air flow of the air flow meter. The injection parameters of the fuel nozzle 310 of the mixed gas in the chamber 300 are controlled to control the corresponding target fuel to enter the mixing chamber 300; the air and fuel in the mixing chamber 300 are mixed and then enter the compressor 400, and the compressed mixed gas enters the distribution chamber 500 through the pipeline, and then enters each compression ignition pre-combustion chamber in sequence through different pipelines between the compression ignition pre-combustion chamber 100 and the distribution chamber 500; the mixed gas entering the compression ignition pre-combustion chamber is compression ignited, part of it enters the main combustion chamber 200 and ignites the fuel-air mixture in the main combustion chamber 200, and part of it enters the collecting chamber 800 through the pipeline to merge; the mixed gas entering the collecting chamber 800 enters the return air port 211 through the pipeline through the pressure control valve 600, and then is sucked into the main combustion chamber 200 of the engine;

[0069] The inductive heating coil 113 on the pipeline between the distribution chamber 500 and the compression ignition pre-combustion chamber 100 can heat the pipeline and then indirectly heat the internal mixed gas. The microcomputer collects the temperature signal of the second temperature sensor 112, outputs a control signal after comparison, calculation and analysis, and controls the heating amount of the inductive heating coil 113 to ensure the temperature entering the compression ignition pre-combustion chamber 100; the microcomputer collects the pressure signal of the pressure sensor 510 on the distribution chamber 500, outputs a control signal after comparison, calculation and analysis, controls the opening of the pressure control valve 600, and can control the mixed gas pressure in the distribution chamber 500; the microcomputer collects the temperature signal of the first temperature sensor 520 on the distribution chamber 500 and the flow signal of the air flow meter 321, outputs a control signal after comparison, calculation and analysis, controls the opening of the circulating exhaust valve 700 and the speed of the motor 410, and controls the amount of circulating mixed gas, thereby achieving the purpose of controlling the temperature of the mixed gas in the distribution chamber 500;

[0070] When the engine is in the acceleration condition, the flow of the mixed gas is consistent with the steady-state condition mentioned above. The microcomputer collects the speed signals of the speed sensors on the transmission shafts of the compressor 400 and the motor 410, and outputs the control signals after comparison, calculation and analysis to control the speed of the motor 410 to increase rapidly. At the same time, the circulating air release valve 700 is controlled to remain closed to ensure that the air intake of the air supply system increases rapidly. The microcomputer determines the injection parameter changes of the mixed gas fuel nozzle 310 in the mixing chamber 300 through calculation and processing based on the air flow change of the air flow meter 321, and then controls the corresponding target fuel to enter the mixing chamber 300. The microcomputer collects the pressure signal of the pressure sensor 510 on the distribution chamber 500, and outputs the control signals after comparison, calculation and analysis to control the opening of the pressure control valve 600 to ensure that the mixed gas pressure in the distribution chamber meets the target.

[0071] When the engine is in a rapid deceleration condition, the flow of the mixture is consistent with the steady-state condition mentioned above. The microcomputer collects the speed signals of the speed sensors on the transmission shafts of the compressor 400 and the motor 410, and outputs a control signal after comparison, calculation and analysis to control the speed of the motor 410 to decrease rapidly. At the same time, the circulating air release valve 700 is controlled to remain fully open to ensure that the air intake of the air supply system is rapidly reduced; the microcomputer determines the changes in the injection parameters of the mixture fuel nozzle 310 in the mixing chamber 300 through calculation and processing based on the air flow change of the air flow meter 321, and then controls the corresponding target fuel to enter the mixing chamber 300; the microcomputer collects the pressure signal of the pressure sensor 510 on the distribution chamber 500, and outputs a control signal after comparison, calculation and analysis to control the opening of the pressure control valve 600 to ensure that the mixture pressure in the distribution chamber meets the target.

[0072] The control method of the pressure control valve 600 of this embodiment is as follows:

[0073] Step 1: The microcomputer obtains the engine working status;

[0074] Step 2: The microcomputer calculates and determines the initial opening of the pressure control valve 600, and outputs a control signal to the pressure control valve 600;

[0075] Step 3: The microcomputer calculates and determines the target pressure value in the distribution chamber 500, and obtains the pressure signal of the pressure sensor 510 and the actual opening signal of the pressure control valve 600;

[0076] Step 4: Determine whether the pressure in the distribution chamber 500 deviates from the target, if yes, go to step 5, otherwise go to step 6;

[0077] Step 5: The microcomputer calculates and determines the new opening of the pressure control valve 600, and outputs a new opening control signal to the pressure control valve 600. After completion, the process goes to step 1;

[0078] Step 6: The microcomputer outputs a constant opening control signal to the pressure control valve 600, and then goes to step 1.

[0079] The control method of the induction heating coil 113 of this embodiment is as follows:

[0080] Step 1: The microcomputer obtains the engine working status;

[0081] Step 2: The microcomputer calculates and determines the initial signal of the heating power of the induction heating coil 113, and outputs a control signal to the induction heating coil 113;

[0082] Step 3: The microcomputer calculates and determines the target value of the inlet temperature of the compression ignition pre-combustion chamber 100, and obtains the temperature signal of the second temperature sensor 112;

[0083] Step 4: Determine whether the inlet temperature of the compression ignition pre-combustion chamber 100 deviates from the target, if yes, go to step 5, otherwise go to step 6;

[0084] Step 5: The microcomputer calculates and determines a new heating power signal, and outputs a new heating power control signal to the induction heating coil 113. After completion, go to step 1;

[0085] Step 6: The microcomputer outputs a constant heating power control signal to the induction heating coil 113, and then goes to step 1.

[0086] The control method of the motor 410 of the compressor 400 of this embodiment is as follows:

[0087] Step 1: The microcomputer obtains the engine working status;

[0088] Step 2: The microcomputer calculates and determines the initial control signal of the motor 410, and outputs the control signal to the motor 410;

[0089] Step 3: The microcomputer calculates and determines the air flow target value of the air flow meter 321, and obtains the actual air flow signal of the air flow meter 321;

[0090] Step 4: Determine whether the air flow rate deviates from the target. If yes, go to step 5; otherwise, go to step 6.

[0091] Step 5: The microcomputer calculates and determines a new control signal for the motor 410, and outputs the new control signal to the motor 410. After completion, the process goes to step 1;

[0092] Step 6: The microcomputer outputs a constant control signal to the motor 410, and then goes to step 1.

[0093] The control method of the mixed gas fuel nozzle 310 of this embodiment is as follows:

[0094] Step 1: The microcomputer obtains the engine working status;

[0095] Step 2: The microcomputer calculates and determines the initial control signal of the mixed gas fuel nozzle 310, and outputs the control signal to the mixed gas fuel nozzle 310;

[0096] Step 3: The microcomputer obtains the actual air flow signal of the air flow meter 321 and calculates and determines the new control signal of the mixed gas fuel nozzle 310;

[0097] Step 4: The microcomputer outputs a new control signal to the mixed gas fuel nozzle 310, and then goes to step 1;

[0098] The control method of the circulating air release valve 700 of this embodiment is as follows:

[0099] Step 1: The microcomputer obtains the engine working status;

[0100] Step 2: Determine whether the engine is in a rapid acceleration state, if so, go to step 3, otherwise go to step 4;

[0101] Step 3: The microcomputer outputs a fully closed control signal to the circulating air release valve 700, and after completion, proceed to step 1;

[0102] Step 4: Determine whether the engine is in a rapid deceleration state, if so, go to step 5, otherwise go to step 6;

[0103] Step 5: The microcomputer outputs a full-open control signal to the circulating air release valve 700, and after completion, proceed to step 1;

[0104] Step 6: The microcomputer calculates and determines the initial control signal of the circulating air release valve 700, and outputs the initial control signal to the circulating air release valve 700;

[0105] Step 7: The microcomputer calculates and determines the target temperature value of the mixed gas in the distribution chamber 500, and obtains the temperature signal of the first temperature sensor 520 and the actual opening signal of the circulating air release valve 700;

[0106] Step 8: Determine whether the temperature of the mixed gas in the distribution chamber 500 deviates from the target, if yes, go to step 9, otherwise go to step 10;

[0107] Step 9: The microcomputer calculates and determines the new opening signal of the circulating air release valve 700, and outputs the new opening signal to the circulating air release valve 700. After completion, the process goes to step 1;

[0108] Step 10: The microcomputer outputs a constant opening control signal to the circulating air release valve 700, and after completion, proceed to step 1.

[0109] The present invention manages the temperature, pressure, composition and flow rate of the mixture to ensure that the mixture in the compression ignition pre-combustion chamber 100 ignites reliably and stably at the right time; the combustible mixture in the compression ignition pre-combustion chamber 100 is compressed and ignited, the ignition in the compression ignition pre-combustion chamber 100 is more stable, the cycle variation of the internal combustion engine is reduced, and the internal combustion engine can use a thinner mixture. In particular, for fuels with high ignition energy, such as ammonia fuel, it is difficult for existing ignition devices to ignite the mixture in the pre-combustion chamber, but the compression ignition of the present invention can make the pre-combustion chamber mixture reliably self-ignite or cause a partial combustion reaction, making it possible to use such fuels in internal combustion engines.

[0110] The preferred embodiments of the present invention are specifically described above, but the invention is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. An air supply system for a compression ignition pre-combustion chamber of an engine, characterized in that: include: An engine having at least one compression ignition pre-combustion chamber and a main combustion chamber connected to each other, wherein the compression ignition pre-combustion chamber is provided with a scavenging air inlet and a scavenging air exhaust; An air supply pipeline includes a mixing chamber, a compressor, a distribution chamber, a pressure control valve, and a circulating air release valve. The mixing chamber, the compressor, the distribution chamber, and the circulating air release valve are connected in a closed loop. The distribution chamber is connected to the scavenging air inlet. The mixing chamber is connected to a mixed gas fuel nozzle and an air intake pipe. The pressure control valve is connected to the scavenging air exhaust port. A heating component is provided between each of the scavenging air inlet and the distribution chamber. The invention also includes an air supply control method for an engine compression ignition pre-combustion chamber applicable to the air supply system, the air supply control method comprising: When the engine is in a steady-state condition, the outside air enters the mixing chamber through the air intake pipe under the action of the pressure difference. According to the air flow rate of the air intake pipe, the mixed gas fuel nozzle is controlled to let the corresponding target fuel enter the mixing chamber. The compressor delivers the compressed mixed gas to the distribution chamber, and then enters each compression ignition pre-combustion chamber in sequence through different pipelines between the compression ignition pre-combustion chamber and the distribution chamber. At the same time, the temperature of the mixed gas entering each compression ignition pre-combustion chamber is heated by the heating component. The pressure of the mixed gas in the distribution chamber is controlled by the opening of the pressure control valve. The amount of the circulating mixed gas is controlled by controlling the opening of the circulating air release valve and the compression power of the compressor, so as to achieve the purpose of controlling the temperature of the mixed gas in the distribution chamber. When the engine is in acceleration condition, the compression power of the compressor is controlled to increase on the basis of steady-state condition, the circulating air release valve is controlled to remain closed, so that the air intake volume of the air intake pipe increases rapidly, the mixed gas fuel nozzle is controlled to allow the corresponding target fuel to enter the mixing chamber, and the opening of the pressure control valve is controlled to ensure that the mixed gas pressure in the distribution chamber meets the target; When the engine is in a rapid deceleration condition, the compression power of the compressor is controlled to decrease on the basis of the steady-state condition, and the circulating air bleed valve is controlled to remain fully open to rapidly reduce the air intake volume of the air intake pipe. The mixture fuel nozzle is controlled to allow the corresponding target fuel to enter the mixing chamber, and the opening of the pressure control valve is controlled to ensure that the mixture pressure in the distribution chamber meets the target.

2. The gas supply system according to claim 1, characterized in that: The air intake pipe is provided with an air flow meter and a heat exchanger.

3. The gas supply system according to claim 1, characterized in that: The engine further comprises an intake passage connected to the main combustion chamber, the intake passage is provided with an air return port, and the pressure control valve is connected between the scavenging exhaust port and the air return port.

4. The gas supply system according to claim 3, characterized in that: A collecting chamber is provided between the pressure control valve and the scavenging exhaust port.

5. The gas supply system according to claim 3, characterized in that: An air filter is arranged at the inlet end of the air intake passage, and an air intake port connected to an air intake pipe is arranged in the air intake passage, and both the air intake port and the air return port are located downstream of the air filter.

6. The gas supply system according to claim 5, characterized in that: The air intake pipe is provided with a one-way valve.

7. The gas supply system according to claim 1, characterized in that: A scavenging air intake pipe is connected between the scavenging air intake port and the distribution chamber. The heating component is an induction heating coil wrapped around the outer wall of the scavenging air intake pipe. The scavenging air intake port is provided with a second temperature sensor.

8. The gas supply system according to claim 1, characterized in that: The distribution chamber is provided with a pressure sensor and a first temperature sensor.

9. The gas supply system according to any one of claims 1 to 8, characterized in that: It also includes a control unit, which is used to detect the working state of the engine, the flow of the air intake pipe, the pressure and temperature of the distribution chamber, and the temperature of the scavenging air intake port, so as to control the compression power of the compressor, the injection of the mixture fuel nozzle, the heating component, the circulation bleed valve and the opening of the pressure control valve.

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