Constant-volume combustion device for simulating eddy current and tumble motion

Abstract

The invention discloses a constant-volume combustion device for simulating vortex and tumble motion, and relates to the technical field of engine experiments, the constant-volume combustion device comprises a high-temperature combustion mechanism, a combustion chamber is arranged in the high-temperature combustion mechanism, an air inlet one-way valve and an exhaust one-way valve are mounted on the high-temperature combustion mechanism, and the air inlet one-way valve is used for injecting magnetofluid particles and combustible mixed gas in sequence; the whole electromagnetic driving mechanism is of an annular structure, the electromagnetic driving mechanism is vertically and movably arranged so as to switch whether the electromagnetic driving mechanism wraps the high-temperature combustion mechanism or not, and the electromagnetic driving mechanism is used for driving the magnetofluid particles to move in the tangential direction of the combustion chamber or pushing the magnetofluid particles to roll in the axial direction of the combustion chamber; and the combustible mixed gas is driven to form an annular vortex or a vertical tumble flow. The magnetic fluid is driven by the electromagnetic driving mechanism through the rotating magnetic field and the gradient magnetic field to form eddy current and tumble flow, abrasion and complexity of a traditional mechanical structure are avoided, and durability and operation stability of the device are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of engine experiments, and particularly to a constant volume combustion device for simulating vortex and tumble motions. Background Art

[0002] As an important experimental device for studying the combustion characteristics of internal combustion engines, constant volume combustion devices are widely used to simulate flame propagation, pressure changes, and the combustion process of combustible mixtures. In internal combustion engines, vortex (circumferential rotating airflow) and tumble (axial tumbling airflow) are key airflow patterns that affect combustion efficiency and emissions, and can significantly improve the mixing effect of fuel and air and optimize the flame propagation path. Therefore, accurately reproducing vortex and tumble in a constant volume combustion device is of great value for understanding the combustion mechanism and improving engine design.

[0003] When existing constant volume combustion devices simulate vortex and tumble, they usually rely on mechanical structures or external air sources to control airflow movement. For example, some devices set spoiler plates or guide vanes in the combustion chamber, and use the flow path of the combustible mixture to form rotating or tumbling airflow; other designs use nozzles to inject gas at specific angles, or introduce a predetermined airflow pattern through an external air source (such as compressed air or a blower). These methods achieve airflow simulation to a certain extent, but there are obvious deficiencies.

[0004] First of all, mechanical structures such as spoiler plates and nozzles are prone to wear or deformation in the high-temperature and high-pressure combustion environment, resulting in a decline in the performance of the airflow generation device over time, affecting the long-term stability and repeatability of experiments. Secondly, the airflow distributions generated by these methods are often not uniform enough. For example, the airflow ejected by the nozzle may be too strong in local areas and weak in other areas; the spoiler plate may have dead corners due to its fixed position, making it difficult to form an ideal vortex or tumble pattern. Summary of the Invention

[0005] The purpose of the present invention is to provide a constant volume combustion device for simulating vortex and tumble motions, which solves the problem that existing constant volume combustion devices usually rely on mechanical structures or external air sources to control airflow movement when simulating vortex and tumble, and these methods have obvious deficiencies.

[0006] The present invention solves the above technical problems through the following technical solutions. The present invention includes: A high-temperature combustion mechanism, which has a combustion chamber inside. An intake check valve and an exhaust check valve are installed on the high-temperature combustion mechanism. The intake check valve is used to inject magnetic fluid particles and combustible mixture successively. The electromagnetic drive mechanism has an overall annular structure. The electromagnetic drive mechanism is vertically movable to switch whether the high-temperature combustion mechanism is wrapped by the electromagnetic drive mechanism. The electromagnetic drive mechanism is used to drive the magnetohydrodynamic particles to move tangentially along the combustion chamber or push the magnetohydrodynamic particles to tumble axially along the combustion chamber, so as to drive the combustible mixture to form a circumferential eddy or a vertical tumbling flow; The ignition electrode is installed on the high-temperature combustion mechanism and is used to ignite the moving combustible mixture; The high-speed camera is installed on the high-temperature combustion mechanism and is used to record the dynamic phenomena during the combustion process.

[0007] Preferably, the volume of the combustion chamber of the high-temperature combustion mechanism is set to be constant, and it includes a tank body and a sealing cover sealed at the port of the tank body.

[0008] Preferably, the volume of the combustion chamber of the high-temperature combustion mechanism is adjustable. It includes a cylindrical wall, the upper port of the cylindrical wall is sealed with a sealing cover, and a movable sealing plate is sealed and slidably arranged in the lower inner cavity. And the lower port of the cylindrical wall is installed with an electric push rod through a mounting plate, and the telescopic end of the electric push rod is connected to the movable sealing plate to adjust the volume of the combustion chamber.

[0009] Preferably, arc-shaped transition parts are arranged at the upper and lower corners of the combustion chamber to blunt the corners.

[0010] Preferably, the electromagnetic drive mechanism includes a circumferential coil module and an axial coil module distributed vertically; The circumferential coil module includes a plurality of first coils distributed annularly and a first annular housing for accommodating the plurality of first coils. The circumferential coil module generates a rotating magnetic field by applying a three-phase alternating current to drive the magnetohydrodynamic particles to move tangentially along the combustion chamber to form a circumferential eddy; The axial coil module includes a plurality of second coils distributed vertically and a second annular housing for accommodating the plurality of second coils. The axial coil module generates an axial gradient magnetic field by applying a gradient current to push the magnetohydrodynamic particles to tumble along the height direction to form a vertical tumbling flow.

[0011] Preferably, the number of the first coils is 6 - 12, and the number of the second coils is 3 - 6.

[0012] Preferably, the high-temperature combustion mechanism is horizontally rotatably installed on a mounting base through a rotating mechanism to realize the horizontal rotation of the high-temperature combustion mechanism.

[0013] Preferably, the rotating mechanism includes an annular slide rail and slider structure for rotatably connecting the mounting base and the high-temperature combustion mechanism, and an internal gear ring is fixed to the lower end of the high-temperature combustion mechanism. A motor is fixed to the inner wall of the mounting base through a mounting bracket, and a gear is fixed to the output end of the motor. The gear is meshed with the internal gear ring.

[0014] Preferably, a temperature sensor and a pressure sensor are installed on the high-temperature combustion mechanism.

[0015] Preferably, a heating wire is arranged outside the high-temperature combustion mechanism for heating the magnetic fluid particles in the high-temperature combustion mechanism to vaporize them and uniformly mixing them with the combustible mixture gas in the combustion chamber; A protective cover fixed to the high-temperature combustion mechanism is arranged outside the heating wire.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The electromagnetic drive mechanism of the present invention uses a rotating magnetic field and a gradient magnetic field to drive the magnetic fluid to form eddy currents and rolling currents, avoiding the wear and complexity of traditional mechanical structures (such as spoiler plates, nozzles), improving the durability and operating stability of the device, and at the same time achieving non-contact precise control of the airflow field; 2. The rotating design and volume adjustable function of the high-temperature combustion mechanism, combined with the eddy currents and rolling currents generated by the circumferential coil module and the axial coil module, can dynamically simulate the complex airflow field in the internal combustion engine cylinder from the intake to the compression stage, significantly improving the correlation between the experimental results and the actual working conditions; 3. The vertical movement of the electromagnetic drive mechanism switches between the eddy current and rolling current modes, the electric push rod adjusts the volume of the combustion chamber, and the motor controls the rotation speed, enabling the device to adapt to different experimental requirements (such as different compression ratios, airflow intensities), expanding the research scope and application scenarios; 4. The detachable sealing cover is convenient for cleaning and maintenance, the heating wire efficiently vaporizes the magnetic fluid to reduce energy consumption, and the time separation operation strategy optimizes the working coordination of the electrical appliances and the magnetic field, simplifying the operation process and improving the energy utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a three-dimensional structure schematic diagram of the present invention; Figure 2 is a structure schematic diagram of the electromagnetic drive mechanism; Figure 3 is a three-dimensional structure schematic diagram of the high-temperature combustion mechanism; Figure 4 is a sectional three-dimensional structure schematic diagram of the high-temperature combustion mechanism from the first perspective; Figure 5 is a sectional three-dimensional structure schematic diagram of the high-temperature combustion mechanism from the second perspective; Figure 6It is a schematic cross-sectional plane structure diagram of a high-temperature combustion mechanism.

[0018] The numbers in the figure represent: 11 - circumferential coil module; 12 - axial coil module; 13 - first coil; 14 - second coil; 2 - high-temperature combustion mechanism; 21 - cylinder wall; 22 - sealing cover; 23 - arc transition part; 24 - movable sealing plate; 25 - electric push rod; 3 - ignition electrode; 41 - intake check valve; 42 - exhaust check valve; 51 - temperature sensor; 52 - pressure sensor; 6 - heating wire; 61 - protective cover; 7 - high-speed camera; 71 - annular slide rail slider structure; 72 - internal gear ring; 73 - gear; 74 - motor; 8 - mounting base. Specific embodiments

[0019] The following further elaborates on the above and other technical features and advantages of the present invention in conjunction with the accompanying drawings.

[0020] Embodiment 1, this embodiment provides a technical solution: a constant-volume combustion device for simulating eddy current and tumble motion, as Figures 1 to 6 shown, including a high-temperature combustion mechanism 2, an electromagnetic drive mechanism, an ignition electrode 3, and a high-speed camera 7. The ignition electrode 3 and the high-speed camera 7 are installed on the high-temperature combustion mechanism 2. The ignition electrode 3 is used to ignite the combustible mixture in motion, and the high-speed camera 7 is used to record the dynamic phenomena during the combustion process. Moreover, each component is connected to a control system (controller or computer) through a data transmission line to control the operation of each component through the control system or transmit the collected data to the control system.

[0021] The high-temperature combustion mechanism 2 is the core component of the entire device, and its design aims to provide a stable combustion environment for simulating the combustion process and air flow characteristics in the internal combustion engine cylinder. Specifically, the high-temperature combustion mechanism 2 is overall in a cylindrical structure with a combustion chamber inside. This shape design not only facilitates matching with the annular structure of the electromagnetic drive mechanism but also effectively simulates the geometric characteristics of the internal combustion engine cylinder block. The combustion chamber, as the space for accommodating magnetic fluid particles, combustible mixture, and combustion reaction, its cylindrical structure helps the air flow (annular eddy current and vertical tumble) to form regular motion patterns inside, avoiding air flow disorder or dead corners caused by irregular shapes.

[0022] In this embodiment, the volume of the combustion chamber of the high-temperature combustion mechanism 2 is set to be constant. The design principle of this constant volume is as follows: by fixing the volume of the combustion chamber, a stable initial condition is provided, enabling experimental personnel to focus on studying the influence of eddy current and tumble driven by magnetic fluid particles on the combustion process without considering the variable interference brought by volume changes.

[0023] The high-temperature combustion mechanism 2 includes a tank body (i.e., a cylindrical shell structure with an open upper end) and a sealing cover 22 hermetically arranged at the port of the tank body. The sealing cover 22 is installed on the tank body through a snap structure, a threaded part or other detachable fixing structures to ensure the airtightness of the combustion chamber under high temperature and high pressure, and at the same time facilitate the disassembly and cleaning of internal residues (such as combustion products or magnetic fluid particles) after the experiment.

[0024] Both the tank body and the sealing cover 22 are made of quartz glass materials, and its advantages are as follows: 1. The softening point of quartz glass is about 1700 °C, and the working temperature can reach above 1000 - 1200 °C, which can withstand the instantaneous high temperature generated during the combustion process; 2. Quartz glass has high mechanical strength and compressive capacity, can withstand the pressure peak in the combustion chamber, and ensure the structural integrity; 3. Quartz glass has a high light transmittance in the visible light and part of the infrared band, which is suitable for the high-speed camera 7 to capture the flame propagation and air flow movement; 4. As an insulator, quartz glass will not interfere with the electromagnetic fields generated by the circumferential coil and the axial coil, and ensure the normal operation of the magnetic fluid particle drive; 5. Quartz glass has good corrosion resistance to combustion products and is not prone to chemical reactions or degradation.

[0025] There are arc transition parts 23 (the arc transition part 23 is a ring structure, and the vertical section of the inner wall is arc-shaped) between the side wall and the bottom of the tank body and on the outer ring of the inner surface of the sealing cover 22 to achieve corner passivation, so as to facilitate the transition and guidance of the rolling flow turning, reduce the resistance of the air flow at the boundary, make the rolling flow more smooth when tumbling up and down, and avoid affecting the overall flow field uniformity due to the stagnation of the air flow at the corner. This structural design has a certain similarity to the smooth transition of the inner wall of the internal combustion engine cylinder, which helps to improve the authenticity of the simulation.

[0026] An intake check valve 41 and an exhaust check valve 42 are installed on the high-temperature combustion mechanism 2. The intake check valve 41 is used to inject magnetic fluid particles and combustible mixed gas successively, and the exhaust check valve 42 is used to discharge the waste gas generated by combustion. The one-way design of the intake check valve 41 allows gas to be injected into the combustion chamber from the outside and prevents the internal gas from flowing back, ensuring the sequentiality and safety of the injection process. At the beginning of the experiment, first inject the vaporized magnetic fluid particles (such as molten potassium salt solution) into the combustion chamber through the intake check valve 41; then inject the premixed combustible mixed gas (such as methane and air), and the two are fused in the combustion chamber. After combustion is completed, the ignition electrode 3 ignites the combustible mixed gas to generate high temperature and high pressure, generating waste gas. The exhaust check valve 42 automatically opens when the internal pressure exceeds the set threshold, discharges the waste gas to the outside, and at the same time prevents the outside air from flowing back, avoiding polluting the combustion chamber environment. The directional flow characteristics of the check valve ensure the efficient and controlled waste gas discharge process, maintain the clean state of the combustion chamber before and after the experiment, and prepare for the next experiment.

[0027] In this embodiment, the magnetohydrodynamic (MHD) microparticles are stored in a high-pressure and high-temperature resistant sealed container in gaseous form (made of stainless steel or titanium alloy, with a volume of about 0.5 - 1 L). The internal pressure of the container is maintained at 5 - 10 bar, and the temperature is kept at 300 - 500 °C (higher than the vaporization point of the MHD microparticles. For example, the vaporization temperature of the potassium salt solution is about 300 °C) to ensure that the MHD microparticles are always in gaseous state.

[0028] The combustible gas mixture is stored in an external gas proportioning device and connected to the intake check valve 41 through a pipeline. After injecting the MHD microparticles, the intake check valve 41 is opened again, and the pre-mixed combustible gas mixture is slowly injected into the combustion chamber. The intake check valve 41 ensures unidirectional gas flow, fully mixes with the vaporized MHD microparticles, and then the valve is closed to maintain the sealed state of the combustion chamber.

[0029] A temperature sensor 51 and a pressure sensor 52 are installed on the high-temperature combustion mechanism 2. Specifically, the temperature sensor 51 and the pressure sensor 52 are embedded in the tank body or the sealing cover of the high-temperature combustion mechanism 2, respectively, for real-time monitoring of the temperature and pressure changes in the combustion chamber. The temperature sensor 51 may adopt thermocouple or infrared temperature measurement technology, which can withstand the high temperature during the combustion process and accurately capture the dynamic data of flame propagation and heat distribution. The pressure sensor 52 may be a piezoresistive or capacitive sensor, which senses the peak pressure generated by combustion and records the intensity and process of the combustion reaction. The temperature sensor 51 and the pressure sensor 52 are connected to an external data acquisition system through wires, and transmit real-time signals to the control system for analyzing the influence of the airflow field on the combustion characteristics.

[0030] The electromagnetic driving mechanism is a ring-shaped structure as a whole, with an inner cavity formed in the middle. The inner diameter of the inner cavity is slightly larger than the outer diameter of the high-temperature combustion mechanism 2. The electromagnetic driving mechanism is vertically movable, and the high-temperature combustion mechanism 2 is vertically corresponding to the inner cavity of the electromagnetic driving mechanism. When the electromagnetic driving mechanism moves vertically, it can switch whether to wrap the high-temperature combustion mechanism 2. The electromagnetic driving mechanism is used to drive the MHD microparticles to move tangentially along the combustion chamber or push the MHD microparticles to roll axially along the combustion chamber, so as to drive the combustible gas mixture to form a circumferential eddy current or a vertical rolling flow.

[0031] The electromagnetic driving mechanism includes a circumferential coil module 11 and an axial coil module 12 distributed vertically, and the circumferential coil module 11 and the axial coil module 12 are vertically displaced by a lifting device (not shown in the figure). The lifting device can adopt existing electric slide table structures, hydraulic telescopic devices, etc. When the lifting device drives the electromagnetic driving mechanism to move downward, the circumferential coil module 11 or the axial coil module 12 can respectively wrap the combustion chamber; when moving upward, it disengages from the combustion chamber to switch the working mode.

[0032] The circumferential coil module 11 includes a plurality of first coils 13 distributed annularly and a first annular housing for accommodating the plurality of first coils 13. The number of the first coils 13 is 6 - 12. The circumferential coil module 11 generates a rotating magnetic field by applying a three-phase alternating current, so as to drive the magnetohydrodynamic particles to move tangentially along the combustion chamber and form a circumferential eddy current.

[0033] The axial coil module 12 includes a plurality of second coils 14 distributed vertically and a second annular housing for accommodating the plurality of second coils 14. The number of the second coils 14 is 3 - 6. The axial coil module 12 generates an axial gradient magnetic field by applying a gradient current, and pushes the magnetohydrodynamic particles to tumble along the height direction to form a vertical rolling flow.

[0034] Both the first annular housing and the second annular housing are made of high-temperature non-conductive materials (such as ceramics or engineering plastics) to accommodate and protect the coils and avoid interfering with the magnetic field at the same time.

[0035] The high-temperature combustion mechanism 2 realizes the orderly injection of magnetohydrodynamic particles and combustible mixed gas through the intake one-way valve 41, and the electromagnetic drive mechanism drives them to form a circumferential eddy current or a vertical rolling flow. During the combustion process, the temperature sensor 51 and the pressure sensor 52 continuously monitor the environmental parameters, and the exhaust gas is discharged through the exhaust one-way valve 42 after ignition. The whole process forms a closed-loop gas management and data acquisition system: from injection to combustion and then to exhaust gas emission, combined with real-time monitoring, to ensure that the experimental conditions are controllable and the data is credible.

[0036] Principle of generating circumferential eddy current: When the electromagnetic drive mechanism moves to the position where the circumferential coil module 11 wraps the high-temperature combustion mechanism 2, a three-phase alternating current (for example, frequency 50 Hz, current 0.1 - 1 A) is applied to the first coils 13. The periodic changes of the three-phase current in time and space enable the plurality of first coils 13 to jointly generate a magnetic field rotating along the circumference of the combustion chamber. The direction of the rotating magnetic field continuously changes around the axis of the combustion chamber, similar to the principle of the rotating magnetic field in a motor. Since the magnetohydrodynamic particles are conductive, the magnetohydrodynamic particles are driven by the Lorentz force in the magnetic field and move tangentially to form a circumferential rotation trajectory. The magnetohydrodynamic particles transfer momentum to the combustible mixed gas through viscous drag and turbulent diffusion, driving the combustible mixed gas to move, and finally forming a circumferential eddy current. The speed and intensity of the circumferential eddy current can be controlled by adjusting the current frequency and amplitude to simulate the rotating airflow in the intake stage of an internal combustion engine.

[0037] Principle of vertical tumbling flow generation: When the electromagnetic drive mechanism moves to the position where the axial coil module 12 wraps the high-temperature combustion mechanism 2, a gradient direct current (for example, increasing from the bottom to the top, with a gradient of 0.1 T / m) is passed through the second coil 14 to generate an axial gradient magnetic field. The magnetic field strength varies along the height of the combustion chamber. The magnetohydrodynamic particles will be pushed towards the direction with a weaker magnetic field. For example, the magnetic field is stronger at the bottom and weaker at the top, driving the magnetohydrodynamic particles to move from the strong magnetic field end to the weak magnetic field end. After the magnetohydrodynamic particles rise to the top, they are blocked by the combustion chamber wall and the convection of the combustible mixture gas, and then descend along the wall, forming an up-and-down tumbling circular trajectory. The magnetohydrodynamic particles transfer momentum to the combustible mixture gas through viscous drag and turbulent diffusion. The tumbling of the magnetohydrodynamic particles drives the combustible mixture gas to form a vertical tumbling flow. The intensity of the tumbling flow is adjusted by the current gradient, simulating the axial air flow in the compression stage of an internal combustion engine.

[0038] In the above, after the magnetohydrodynamic particles are blocked by the combustion chamber wall, a backflow will be generated due to the flow characteristics of the surrounding combustible mixture gas. The specific reasons are as follows: 1. Pressure difference and density change: When the magnetohydrodynamic particles move upward, they drive the combustible mixture gas to flow together, resulting in a slight increase in the gas density in the top region and a relative decrease at the bottom. This local pressure and density imbalance will drive the gas to flow back from the top to the bottom; 2. Viscous effect: The viscous friction between the magnetohydrodynamic particles and the combustible mixture gas causes the gas to follow the movement of the magnetohydrodynamic particles. When the magnetohydrodynamic particles reach the top, the inertia of the combustible mixture gas will continue to push a part of the magnetohydrodynamic particles and the combustible mixture gas downward along the wall, forming a backflow path; 3. Three-dimensional flow: Since the combustion chamber is cylindrical, the backflow of the magnetohydrodynamic particles and the combustible mixture gas will not be completely along a straight line, but form an annular circular path along the wall. This path is similar to the "barrel effect" in convection. The magnetohydrodynamic particles rise from the bottom, descend along the wall after reaching the top, and return to the bottom.

[0039] In the vertical tumbling flow movement, the outer magnetohydrodynamic particles are close to the wall. When the upward airflow is blocked at the top, the combustible mixture gas near the wall starts to flow downward due to the viscous effect and pressure difference. This downward flow "drags" the outer magnetohydrodynamic particles downward, rather than the magnetic field directly pushing them downward. At this time, the drag force (viscous force and inertial force) of fluid mechanics exceeds the upward thrust of the magnetic field on the magnetohydrodynamic particles to ensure the smooth downward displacement of the magnetohydrodynamic particles located on the outside.

[0040] Embodiment 2: This embodiment is a further optimization based on Embodiment 1. The same parts as the foregoing technical solutions will not be described herein again. As Figures 3 to 6 shown, in order to better implement the present invention, the following setting method is particularly adopted: The volume of the combustion chamber of the high-temperature combustion mechanism 2 is adjustable to meet different experimental requirements. In this embodiment, the high-temperature combustion mechanism 2 includes a barrel wall 21. The upper port of the barrel wall 21 is hermetically provided with a sealing cover 22 (the installation method of the sealing cover 22 is the same as that in the first embodiment and will not be elaborated here). A movable sealing plate 24 is hermetically and slidably arranged in the lower inner cavity of the barrel wall 21. The barrel wall 21, the sealing cover 22 and 24 are all made of quartz glass. The lower port of the barrel wall 21 is installed with an electric push rod 25 through a mounting plate. The telescopic end of the electric push rod 25 is connected to the movable sealing plate 24. By telescoping the telescopic end of the electric push rod 25, the position of the movable sealing plate 24 is adjusted to realize the adjustment of the volume of the combustion chamber.

[0041] Arc-shaped transition parts 23 are arranged on the outer ring of the lower side of the sealing cover 22 and the outer ring of the upper side of the movable sealing plate 24 to blunt the corners, reduce the resistance of the air flow at the boundary, enable the vertical tumbling flow to still tumble smoothly when the volume changes, and avoid turbulent flow or dead corners.

[0042] In this embodiment, the volume of the combustion chamber is adjusted by the electric push rod 25 to meet the experimental requirements of different compression ratios or air flow conditions, expanding the application range of the device.

[0043] It should be noted that: An electromagnetic shielding layer is added around the control circuit and the housing of the electric push rod 25. For example, a shielding cover is made of a high magnetic permeability material (such as Mu-metal or soft iron) to wrap the housing of the electric push rod 25. The power cord and the signal line are added with shielding sleeves such as braided copper mesh or aluminum foil sleeves and grounded to prevent the interference current generated by magnetic field induction.

[0044] Embodiment 3 is a further optimization on the basis of Embodiment 1. The same parts as the foregoing technical solutions will not be elaborated here. As Figures 4 to 6 shown, in order to better implement the present invention, the following setting method is particularly adopted: The high-temperature combustion mechanism 2 is horizontally rotatably installed on an installation base 8 through a rotating mechanism, so that the high-temperature combustion mechanism 2 rotates during the experiment to realize the horizontal rotation of the high-temperature combustion mechanism.

[0045] The rotating mechanism includes an annular slide rail and slider structure 71 that rotatably connects the installation base 8 and the high-temperature combustion mechanism 2. The annular slide rail and slider structure 71 includes an annular slide rail fixed to the installation base 8 and an annular slider fixed to the bottom of the high-temperature combustion mechanism 2, and the annular slide rail is slidably connected to the annular slider.

[0046] An internal gear ring 72 is fixed to the lower end of the high-temperature combustion mechanism 2. The inner wall of the installation base 8 is fixed with a motor 74 through a mounting bracket. The output end of the motor 74 is fixed with a gear 73, and the gear 73 is meshed with the internal gear ring 72.

[0047] It should be noted that: An electromagnetic shielding layer is added around the control circuit and the housing of the motor 74. For example, a shielding cover is made of a high magnetic permeability material (such as Mu-metal or soft iron) to wrap the motor housing. The power line and signal line of the motor are equipped with shielding sleeves such as braided copper mesh or aluminum foil sleeves and are grounded to prevent the induction of magnetic fields from generating interference currents.

[0048] When the motor 74 is running, the high-temperature combustion mechanism 2 can be driven to rotate through the cooperation of the gear 73 and the internal gear ring 72. When the high-temperature combustion mechanism 2 rotates, the magnetic fluid particles and the combustible mixture inside it are subjected to centrifugal force and shear force, generating additional rotational disturbances. The superposition of this mechanical rotation and the eddy current generated by the circumferential coil module 11 enhances the complexity of the circumferential air flow and forms a stronger turbulent effect; combined with the tumble generated by the axial coil module 12, it may form a spiral or composite air flow pattern. The disturbances introduced by rotation simulate the dynamic air flow changes in the internal combustion engine cylinder caused by piston movement, intake swirl, or crankshaft rotation, making the experimental conditions closer to the actual working conditions. The arc transition part 23 in the combustion chamber further optimizes the smoothness of the rotating air flow and reduces the boundary resistance.

[0049] Embodiment 4 is a further optimization based on Embodiment 1. The same parts as the foregoing technical solutions will not be described in detail herein. As Figures 4 to 6 shown, in order to better implement the present invention, the following setting method is particularly adopted: In this embodiment, after injecting the magnetic fluid particles into the high-temperature combustion mechanism 2, the high-temperature combustion mechanism 2 is heated, so that the magnetic fluid particles are vaporized and uniformly mixed with the combustible mixture in the combustion chamber. Therefore, a heating wire 6 is arranged outside the high-temperature combustion mechanism 2, and a protective cover 61 fixed to the high-temperature combustion mechanism 2 is arranged outside the heating wire 6.

[0050] The heating wire 6 is wound around the outside of the high-temperature combustion mechanism 2 and is usually distributed in a spiral or uniform grid pattern. The heating wire 6 is made of a high-temperature resistant resistance material such as nickel-chromium alloy or iron-chromium-aluminum alloy, with a working temperature of up to 500 - 800 °C and a power of about 100 - 300 W, depending on the size of the combustion chamber and the heating requirements. The protective cover 61 is a cylindrical shell fixed to the outside of the high-temperature combustion mechanism 2 and can be made of a high-temperature resistant metal (such as stainless steel) or ceramic material. The inside is filled with an insulating layer (such as ceramic fiber) and maintains a certain gap from the heating wire 6 to protect the heating wire and reduce heat dissipation. The outer wall of the protective cover 61 is attached with copper foil to shield the magnetic field.

[0051] The above are only the preferred embodiments of the present invention, which are illustrative rather than restrictive to the present invention. Those skilled in the art understand that many changes, modifications, or even equivalents can be made within the spirit and scope defined by the claims of the present invention, but all will fall within the protection scope of the present invention.

Claims

1. A constant volume combustion device simulating swirl and tumble motion, characterized in that: include: A high-temperature combustion mechanism (2) having a combustion chamber therein, wherein an intake check valve (41) and an exhaust check valve (42) are installed on the high-temperature combustion mechanism (2), wherein the intake check valve (41) is used to sequentially inject magnetic fluid particles and a combustible mixed gas; The electromagnetic drive mechanism is an annular structure as a whole. The electromagnetic drive mechanism is arranged to move vertically to switch whether the electromagnetic drive mechanism wraps the high-temperature combustion mechanism (2). The electromagnetic drive mechanism is used to drive the magnetic fluid particles to move tangentially along the combustion chamber or to push the magnetic fluid particles to roll axially along the combustion chamber, so as to drive the combustible mixed gas to form an annular vortex or a vertical tumbling flow; An ignition electrode (3) is mounted on the high-temperature combustion mechanism (2) and is used to ignite the combustible mixed gas in motion; A high-speed camera (7) is installed on the high-temperature combustion mechanism (2) and is used to record dynamic phenomena during the combustion process.

2. The constant volume combustion device for simulating swirl and tumble motion according to claim 1, characterized in that: The volume of the combustion chamber of the high-temperature combustion mechanism (2) is set to be constant, and comprises a tank body and a sealing cover (22) sealed at a port of the tank body.

3. The constant volume combustion device for simulating swirl and tumble motion according to claim 1, characterized in that: The volume of the combustion chamber of the high-temperature combustion mechanism (2) is adjustable, and comprises a cylinder wall (21), an upper end of the cylinder wall (21) being sealed with a sealing cover (22), a lower end inner cavity being sealingly slidably provided with a movable sealing plate (24), and a lower end of the cylinder wall (21) being mounted with an electric push rod (25) via a mounting plate, the telescopic end of the electric push rod (25) being connected to the movable sealing plate (24) to adjust the volume of the combustion chamber.

4. The constant volume combustion device for simulating swirl and tumble motion according to claim 2 or 3, characterized in that: Arc-shaped transition portions (23) are provided at the upper and lower corners of the combustion chamber to achieve blunt corners.

5. The constant volume combustion device for simulating swirl and tumble motion according to claim 1, characterized in that: The electromagnetic drive mechanism comprises a circumferential coil module (11) and an axial coil module (12) distributed vertically; The circumferential coil module (11) comprises a plurality of first coils (13) distributed in an annular manner and a first annular shell accommodating the plurality of first coils (13); the circumferential coil module (11) generates a rotating magnetic field by passing a three-phase alternating current, driving magnetic fluid particles to move tangentially along the combustion chamber, thereby forming an annular vortex; The axial coil module (12) comprises a plurality of second coils (14) distributed vertically and a second annular shell accommodating the plurality of second coils (14). The axial coil module (12) generates an axial gradient magnetic field by passing a gradient current, thereby driving magnetic fluid particles to tumble in a height direction, thereby forming a vertical tumbling flow.

6. The constant volume combustion device for simulating swirl and tumble motion according to claim 5, characterized in that: The number of the first coils (13) is 6-12, and the number of the second coils (14) is 3-6.

7. The constant volume combustion device for simulating swirl and tumble motion according to claim 1, characterized in that: The high-temperature combustion mechanism (2) is horizontally rotatably mounted on a mounting base (8) via a rotating mechanism, so as to achieve horizontal rotation of the high-temperature combustion mechanism (2).

8. The constant volume combustion device for simulating swirl and tumble motion according to claim 7, characterized in that: The rotating mechanism comprises an annular slide rail structure (71) which rotatably connects the mounting base (8) and the high-temperature combustion mechanism (2), and an inner gear ring (72) is fixed to the lower end of the high-temperature combustion mechanism (2), a motor (74) is fixed to the inner wall of the mounting base (8) via a mounting bracket, a gear (73) is fixed to the output end of the motor (74), and the gear (73) is meshingly connected to the inner gear ring (72).

9. The constant volume combustion device for simulating swirl and tumble motion according to claim 1, characterized in that: A temperature sensor (51) and a pressure sensor (52) are installed on the high-temperature combustion mechanism (2).

10. The constant volume combustion device for simulating swirl and tumble motion according to claim 1, characterized in that: A heating wire (6) is arranged outside the high-temperature combustion mechanism (2) for heating the magnetic fluid particles in the high-temperature combustion mechanism (2) until they are gasified and uniformly mixed with the combustible gas in the combustion chamber; A protective cover (61) fixed to the high-temperature combustion mechanism (2) is provided on the outer side of the heating wire (6).

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