Experimental system and method for liquid fuel high pressure combustion flame-wall interaction

Abstract

The present invention discloses an experimental system and method for the interaction between a liquid fuel high-pressure combustion flame and a wall surface, which relates to the field of engine technology. The present invention simulates different operating conditions inside the engine through a controllable combustion reaction chamber adjusted under a high-pressure range, and uses a flat-plate slit burner to simulate the collision process between the flame and the wall surface in the engine cylinder. At the same time, an electrical automatic control device is used to control the variable conditions in the combustion experiment to achieve a systematic study of the flame-wall physical and chemical reaction process. The experimental system of the present invention can conduct in-depth research on the stability, flame structure and pollutant emissions of the efficient combustion process in the engine in a very short time. In addition, the experimental device integrates the use of Internet of Things technology, which realizes simple operation and visualization of experimental data, reveals the physical and chemical interaction mechanism between the gas phase flame and the solid phase wall surface, and provides an important reference for the improvement and structural optimization of the efficient and clean combustion technology of the engine.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of engines, and particularly relates to an experimental system and method for interaction between high-pressure combustion flame of liquid fuel and wall surface. BACKGROUND

[0002] Internal combustion engine is the main power of road traffic, non-road mobile machinery and national defense equipment in the world, and is one of the most important basic industries in the national economy. The interaction between flame and wall surface widely exists in the combustion system of internal combustion engine, which is a complex system involving gas dynamics, thermodynamics and chemical reaction kinetics. With the promotion of the miniaturization trend of engine, the expansion process of high-temperature and high-pressure gas in the cylinder inevitably collides with the flame and the wall. When the flame contacts the relatively cold wall in a confined space, the significant heat loss between the gas-solid interface will cause the near-wall flame temperature to cool rapidly, causing the combustion chemical reaction to slow down or even stop, resulting in flame instability or incomplete combustion. In addition, the chemical quenching effect of flame-wall plays an important role in high-temperature combustion, and the excessive free radical extinction near the wall also has an adverse effect on fuel ignition and generation of various combustion pollutants, which cannot be ignored.

[0003] In order to reduce greenhouse gas emissions, zero-carbon fuel-liquid fuel dual-fuel engine is considered as a very promising technology. However, the zero-carbon fuel-liquid fuel dual-fuel engine combustion technology still faces such practical problems as poor combustion stability, low thermal efficiency and high NOx emission. Most of the existing researches focus on the influence of changing intake conditions, injection strategies and pilot active fuel and other macro-physical parameters on the operating boundary and combustion characteristics of the engine, while less attention is paid to the regulation of the chemical micro-reaction mechanism of the wall-combustion flame, and even less attention is paid to the combustion of zero-carbon fuel under high pressure. It is of great practical significance to deeply study the thermal-chemical coupling relationship between flame and wall under high pressure for the performance improvement and emission control of combustion devices.

[0004] At present, most of the flat plate slit combustion experiments are mainly focused on natural gas and other gaseous fuels, and the experimental research on high-pressure liquefiable liquid fuel still faces great challenges. In order to solve the problem that the flame behavior is difficult to observe under the actual closed combustion conditions in the cylinder of internal combustion engine, a flat plate slit burner is used to independently study the interaction process between flame and wall, and a pressure controllable combustion reaction chamber is used to simulate the continuously changing actual working pressure, which is a feasible technical idea. The boundary layer of the interaction between flame and wall in the flat plate slit combustion channel is mostly hundreds of microns, and the traditional measurement method often introduces greater experimental error. The on-line optical diagnosis technology has shown its advantages of high resolution, non-invasiveness and high measurement accuracy in complex high-temperature combustion environment, which is a feasible means to solve the above measurement problems.

[0005] In order to explore the combustion organization mode and control strategy for improving the combustion thermal efficiency of the engine, the pressurized liquid fuel is heated and gasified and mixed with the oxidant, the experimental variables such as equivalence ratio, wall temperature, pressure, flame-wall distance and the like are controlled or the wall material is changed, the planar laser-induced fluorescence test system and the high-speed camera system are used to analyze the combustion free radicals formed by the collision of the wall and the flame and the flame development process, and the flue gas analyzer is used to detect the combustion products. During the experiment, a large amount of data needs to be recorded and processed, and various experimental variables need to be controlled synchronously. In view of the fact that the existing experimental platform lacks strong data collection and processing ability, the Internet of Things technology is used to build a data interaction system integrating data collection, variable control, data processing and artificial decision-making, which greatly simplifies the experimental operation process of the experimenters. SUMMARY

[0006] The application provides an experimental system and method for the interaction between high-pressure combustion flame of liquid fuel and wall surface, to solve the problem that the existing test device cannot perform optical diagnosis on the interaction between flame and wall surface in the high-temperature combustion process of liquid fuel under the condition of varying working conditions in a high-pressure range.

[0007] To solve the above technical problems, the application provides an experimental system for the interaction between high-pressure combustion flame of liquid fuel and wall surface, which comprises a pressurizing module, a fuel atomization and gasification module, a pressure-controllable combustion reaction cavity, a T-shaped flat plate slit burner assembly, a distributed temperature monitoring system, an optical diagnosis system, a pressure balance discharge module, a real-time flue gas analysis module and a data integration and interaction system.

[0008] The pressurizing module comprises:

[0009] A pressure supply unit is connected with the pressure-controllable combustion reaction cavity through a high-pressure pipeline.

[0010] A fuel pressurizing unit and an air pressurizing unit are connected with the fuel atomization and gasification module through high-pressure pipelines.

[0011] The fuel atomization and gasification module is connected with the pressure-controllable combustion reaction cavity through a heat preservation conveying pipeline.

[0012] The T-shaped flat plate slit burner assembly is arranged in a pressure controllable combustion reaction cavity for simulating the dynamic interaction process of flame and wall surface under the working condition of an internal combustion engine, the T-shaped flat plate slit burner assembly comprises a slit burner base, a burner body, a T-shaped flat plate slit assembly and a servo-driven flat plate displacement mechanism, the burner body is wrapped with heat preservation material and is inserted with a K-type thermocouple, is fixed below the slit burner base and is connected with a fuel atomization and gasification module through a heat preservation heating pipeline, a T-shaped alloy flat plate is installed on a flat plate linear slide rail on a base platform, the servo-driven flat plate displacement mechanism is arranged on a steel frame platform behind the slit burner base, and a high-frequency response piezoelectric sensor is installed on a column of the steel frame platform;

[0013] The distributed temperature monitoring system collects wall surface temperature of the T-shaped flat plate slit burner assembly and thermal state parameters of a fuel delivery pipeline in real time and transmits to a data integration and interaction system for processing;

[0014] The optical diagnosis system collects transient image information and free radical distribution images of the interaction process of flame and wall surface of the T-shaped flat plate slit assembly in high-temperature combustion and transmits to the data integration and interaction system for processing;

[0015] The pressure balance discharge module is arranged on the pressure controllable combustion reaction cavity to maintain dynamic pressure balance of the pressure controllable combustion reaction cavity;

[0016] The flue gas real-time analysis module collects and analyzes combustion products of the pressure controllable combustion reaction cavity and transmits data signal processed to the data integration and interaction system;

[0017] The data integration and interaction system processes and interacts data from sensors and equipment of the pressurizing module, the fuel atomization and gasification module, the distributed temperature monitoring system, the optical diagnosis system and the flue gas real-time analysis module.

[0018] In some embodiments, the slit burner base is a frame structure, and a high-temperature refractory ceramic plate is arranged on the top of the slit burner base;

[0019] The burner body includes a burner insulation body, a high-frequency ignition unit and a burner nozzle. The burner insulation body is fixedly installed below the slit burner base. The burner insulation body includes insulation material, an electric heating wire and a burner K-type thermocouple. The combustion chamber inside the burner insulation body is connected to the air inlet end of the premixed fuel gas delivery pipeline. The burner K-type thermocouple is arranged on both sides of the burner insulation body to monitor the fuel temperature and judge the gasification condition. The burner nozzle is arranged above the burner insulation body. A burner nozzle is provided on the top of the burner nozzle. The channel of the burner nozzle is a rectangular structure. The top surface of the burner nozzle is flush with the surface of the high-temperature refractory ceramic plate. The high-frequency ignition unit is arranged on the side of the burner nozzle;

[0020] A stepping servo motor is provided on one side of the servo-driven plate displacement mechanism to drive the left and right screws of the servo-driven plate displacement mechanism to rotate. A mobile platform is movably mounted on the servo-driven plate displacement mechanism. A displacement sensor is installed on the servo-driven plate displacement mechanism to monitor the distance between the plates.

[0021] The T-shaped flat plate slit assembly includes a carbon silicon electric heating rod, a high-transmittance quartz plate, two parallel surface-nitrided T-shaped alloy plates, a flat plate K-type thermocouple and a flat plate linear slide; the carbon silicon electric heating rod is vertically arranged in the T-shaped alloy plate, a temperature measuring hole is opened on the side of the T-shaped alloy plate, the flat plate K-type thermocouple is arranged in the temperature measuring hole, the two T-shaped alloy plates are respectively fixed on the two movable platforms of the servo-driven flat plate displacement mechanism, the two T-shaped alloy plates are placed parallel and symmetrically, the high-transmittance quartz plate is fixed above the slit burner base, the two T-shaped alloy plates and the two high-transmittance quartz plates constitute a visible combustion channel, the flat plate linear slide is fixedly installed on the top of the slit burner base, and the T-shaped alloy plate is movably installed on the flat plate linear slide.

[0022] In some embodiments, the pressure supply unit of the pressurizing module includes an air compressor and an air storage tank; the fuel boosting unit of the pressurizing module includes a liquid fuel storage tank and a fuel boosting pump; the air boosting unit of the pressurizing module includes an air high-pressure storage tank and an air boosting pump;

[0023] The output end of the air compressor is connected to the input end of the air storage tank via a pipeline, the output end of the air storage tank is connected to the pressure-controlled combustion reaction chamber via a pipeline, the output end of the liquid fuel storage tank is connected to the input end of the fuel booster pump via a pipeline, and the output end of the air high-pressure storage tank is connected to the input end of the air booster pump via a pipeline;

[0024] The fuel atomization and gasification module includes:

[0025] The fuel pretreatment unit comprises a PID electrically controlled fuel gasification electric heater and a constant flow pump;

[0026] The equivalent ratio accurate regulation unit comprises a first mass flow controller, a second mass flow controller and a fuel premixing tank.

[0027] The output end of the fuel booster pump is connected with the constant flow pump, the PID electrically controlled fuel gasification electric heater and the first mass flow controller through pipes in sequence, the output end of the air booster pump is connected with the input end of the second mass flow controller through a pipe, the output ends of the first mass flow controller and the second mass flow controller are connected with the input end of the fuel premixing tank through pipes, and the output end of the fuel premixing tank is connected with the pressure controllable combustion reaction cavity through a heat preservation conveying pipe after passing through an anti-backfire one-way valve.

[0028] In some embodiments, the pressure controllable combustion reaction cavity comprises a cylinder made of high-strength pressure-resistant steel, the cylinder is provided with three-direction orthogonal observation windows, the three-direction orthogonal observation windows comprise a front observation window, a back observation window and a top observation window, the front observation window, the back observation window and the top observation window are arranged on the front side, the back side and the top of the cylinder respectively, the top of the cylinder is provided with a reaction cavity pressure gauge and an anti-explosion safety valve, the side of the cylinder is respectively provided with a reaction cavity pressure supply pipe, an exhaust pipe and a flue gas collection conveying pipe, the reaction cavity pressure supply pipe is connected with the output end of the air storage tank after connecting with a third electromagnetic valve, the lower part of the cylinder is provided with a premixed fuel gas conveying pipe and a through-cabin part for power supply and signal control line channels, the premixed fuel gas conveying pipe is connected with the fuel premixing tank, and the pipe surface of the premixed fuel gas conveying pipe is wrapped with a pipe heat preservation heating belt.

[0029] In some embodiments, the optical diagnosis system comprises:

[0030] The ICCD camera is arranged right behind the back observation window to realize ns-level time-resolved imaging.

[0031] The tunable light source system comprises an Nd:YAG laser generator and a dye laser, the Nd:YAG laser generator can excite pulsed laser of a set wavelength, and the pulsed laser is introduced into the dye laser to generate dye laser of a specific wavelength required by the experiment.

[0032] The planar laser-induced fluorescence system comprises a sheet light shaping assembly and a high reflectivity optical mirror group, the dye laser passes through the sheet light shaping assembly and is refracted into the combustion channel by the high reflectivity optical mirror group.

[0033] In some embodiments, the flue gas real-time analysis module comprises an online flue gas analyzer, a flue gas collection and conveying pipe, a flue gas collection module, a flue gas collection mobile module, a guide rail, a flue gas collection telescopic spring pipe and a T-shaped ceramic flue gas collection pipe arranged on the side of the flue gas collection module, the flue gas collection telescopic spring pipe is connected with the flue gas collection module, the flue gas collection module is fixed through a cross beam and the flue gas collection mobile modules at both ends, the guide rail is fixedly installed at both ends on the pressure controllable combustion reaction cavity, the flue gas collection mobile module is movably installed on the guide rail, the gas inlet of the flue gas collection and conveying pipe is communicated with the gas outlet of the flue gas collection telescopic spring pipe, and the flue gas collection and conveying pipe is connected with the online flue gas analyzer after connecting a first electromagnetic valve.

[0034] In some embodiments, the pressure balance and discharge module comprises a pressure reducing valve installed at the gas outlet of an exhaust pipe, and a second electromagnetic valve installed on the exhaust pipe, and when the pressure of the pressure controllable combustion reaction cavity exceeds a threshold value, the second electromagnetic valve is opened to release pressure.

[0035] In some embodiments, the distributed temperature monitoring system comprises:

[0036] A temperature controller is electrically connected with the carbon-silicon electric heating rod to realize temperature control of the carbon-silicon electric heating rod.

[0037] A multi-channel temperature acquisition instrument is electrically connected with the flat plate K-type thermocouple and the burner K-type thermocouple to realize synchronous acquisition of temperature signals.

[0038] An infrared thermal imager is used to assist in verifying the surface temperature field distribution.

[0039] In some embodiments, the data integration and interaction system comprises:

[0040] A multi-channel data acquisition module is used for data transmission with each device and sensor through an RS485 to TTL module.

[0041] A PC computer is used for connecting the multi-channel data acquisition module through a USB to TTL module of the control system.

[0042] The application further provides an experimental method for liquid fuel high-pressure combustion flame and wall interaction, specifically comprising the following steps:

[0043] S1: Install the target experimental material plate on the T-shaped alloy flat plate; adjust the distance between the plates: control the movement of the moving platform by the stepping servo motor, monitor the distance between the plates by the displacement sensor, start the temperature controller to heat the flat plate using the carbon-silicon electric heating rod after adjusting the distance between the plates, connect the power supply of the pipeline heat preservation heating belt to preheat the whole pipeline, at the same time, start the air compressor to continuously compress air and store it in the air storage tank, open the third electromagnetic valve to charge the pressure controllable combustion reaction chamber after enough air is compressed, monitor the pressure, and until the required pressure value of the experiment is reached;

[0044] S2: Real-time monitor the combustion chamber pressure and wall temperature, and fuel delivery pipeline preheating by high-frequency response piezoelectric sensor, flat plate K-type thermocouple array and burner K-type thermocouple until the experimental preset conditions are reached;

[0045] S3: The liquid fuel and air in the liquid fuel storage tank and the air high-pressure storage tank are pressurized to the required pressure of the experiment by the fuel booster pump and the air booster pump respectively; after the liquid fuel is pressurized to the required pressure of the experiment, it is output to the electric control fuel gasification electric heater through the delivery pipeline with a fuel pressure gauge by controlling the volume flow of the constant flow pump, and the output constant flow liquid fuel is fully gasified; after the liquid fuel is gasified, it is delivered to the first mass flow controller through the heat preservation delivery pipeline; after the air is pressurized to the required pressure of the experiment, it is delivered to the second mass flow controller through the delivery pipeline with an air pressure gauge; the constant flow pump and the mass flow meter realize accurate control of the equivalence ratio; the fuel / air mixture is fully mixed in the fuel premixing tank, and the premixed gas fuel is delivered to the burner nozzle in the combustion channel of the burner body, and the high-frequency ignition unit ignites the fuel premixed gas at the same time;

[0046] S4: Open the second electromagnetic valve and observe whether the pressure in the combustion chamber fluctuates, wait for the state to be stable and reach the experimental standard, then record the flame development process by high-speed photography, capture the two-dimensional distribution of free radicals by the planar laser-induced fluorescence system, and record the process temperature by the distributed temperature monitoring system;

[0047] S5: After the optical experimental data collection is completed, the flue gas collection moving module is started to move to the center of the adjustable gap T-shaped flat plate slit, the T-shaped ceramic flue gas collection pipe is stretched into the combustion cavity to collect the combustion product gas, and the combustion product analysis is carried out by the external online flue gas analyzer, and finally discharged to the outdoor;

[0048] S6: Data processing, the multi-channel data acquisition module acquires original data, transmits to the PC end computer to generate data packets, and carries out data visualization processing.

[0049] Compared with the related art, the experimental system and method for liquid fuel high-pressure combustion flame and wall interaction provided by the present application has the following beneficial effects:

[0050] The application provides an experimental system and method for liquid fuel high-pressure combustion flame-wall interaction, which simulates different working conditions in an engine through a controllable combustion reaction cavity adjusted in a high-pressure range, and simulates the collision process of the flame in the engine cylinder and the wall through a flat plate slot burner, and simultaneously controls variable conditions in the combustion experiment through an electrical control device, so that the physical and chemical reaction process of the flame-wall is comprehensively and carefully researched; an air compressor and a compressed air storage tank can maintain the experimental condition pressure, a mass flow meter controls the equivalence ratio, a T-shaped alloy flat plate is inserted into a carbon-silicon electric heating rod to control the wall temperature, and a moving platform controlled by a stepping servo motor controls the flat plate spacing and then controls the contact distance of the flame and the wall; and the optical diagnosis system and the distributed temperature monitoring system can more intuitively reflect the small variables and change rules in the flame-wall interaction process from the image and data aspects. Therefore, the experimental system can simulate the stability of the high-efficiency combustion process in the engine in a very short time, the flame structure and the in-depth research on pollutant emission, and the experimental device adopts the Internet of Things technology, is easy to operate, visual experimental data are obtained, the physical and chemical action mechanism between the gas-phase flame and the solid-phase wall is revealed, and corresponding reference is provided for improvement and structure optimization of the high-efficiency clean combustion technology of the engine.

[0051] The application provides an experimental system and method for liquid fuel high-pressure combustion flame-wall interaction, which can obtain the change of the wall instantaneous temperature and the heat flux of the wall by uniformly arranging K-type thermocouple probes of a distributed temperature monitoring system in the inside of the flat plate.

[0052] The application provides an experimental system and method for liquid fuel high-pressure combustion flame-wall interaction, which can accurately adjust the position of a flue gas collection port by arranging a flue gas collection telescopic spring pipe and a T-shaped ceramic flue gas collection pipe controlled by a moving module in the combustion cavity, and collects flue gas for analysis.

[0053] The application provides an experimental system and method for liquid fuel high-pressure combustion flame-wall interaction, which can obtain simulation of different flame-wall collision conditions by arranging an electrical control stepping servo motor to control the movement of the slot flat plate, changing the collision distance of the flame and the wall during combustion.

[0054] The application provides an experimental system and method for liquid fuel high-pressure combustion flame-wall interaction, which can non-invasively measure the flame-wall interaction process by arranging a laser fluorescence induction device and exciting free radical luminescence generated in the combustion flame with specific laser.

[0055] The present invention provides an experimental system and method for the interaction between a liquid fuel high-pressure combustion flame and a wall surface. By designing a thin steel sheet with countersunk nuts on all four sides on the flame contact surface of a flat plate, after tightening the nuts, the thin steel sheet fits tightly to the flat plate. The wall surfaces of different roughness and materials can be removed and replaced, or the wall surface can be coated. This broadens the application range of the experimental system and simulates the influence of the physical and chemical properties of the wall material on the combustion process under high-pressure conditions.

[0056] The present invention provides an experimental system and method for the interaction between a liquid fuel high-pressure combustion flame and a wall surface. By using a data integration and interaction system, sensor data is processed and visualized while synchronously controlling the experimental equipment, and the raw data is stored in an open source database, greatly simplifying the operation of the entire experimental system. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 This is an overall schematic diagram provided for this embodiment.

[0058] Figure 2 for Figure 1 The diagram shows the appearance structure of the pressure-controlled combustion reaction chamber.

[0059] Figure 3 for Figure 1 The structure cross-sectional view of the T-shaped flat plate slot burner in the pressure-controlled combustion reaction chamber is shown.

[0060] Figure 4 This is a structural diagram of the T-shaped flat plate slot burner provided in this embodiment.

[0061] Figure 5 This is a working principle diagram of the data integration and interaction system provided in this embodiment.

[0062] In the figure, the reference signs are as follows: 1, pressure-controllable combustion reaction cavity; 2, online flue gas analyzer; 301, first electromagnetic valve; 302, second electromagnetic valve; 303, third electromagnetic valve; 4, pressure reducing valve; 5, ICCD camera; 6, sheet light shaping assembly; 7, air storage tank; 8, dye laser; 9, Nd:YAG laser generator; 10, air compressor; 11, electrically controlled fuel gasification electric heater; 12, constant flow pump; 131, fuel pressure gauge; 132, air pressure gauge; 14, fuel booster pump; 15, liquid fuel storage tank; 16, air high-pressure storage tank; 17, air booster pump; 181, first mass flow controller; 182, second mass flow controller; 19, fuel premixing tank; 20, one-way valve; 21, multi-channel data acquisition module; 22, temperature controller; 23, PC terminal computer; 24, multi-channel temperature acquisition instrument; 25, T-shaped flat plate slit burner assembly; 26, top observation window; 27, reaction cavity pressure gauge; 28, cylinder; 29, reaction cavity pressure supply pipeline; 30, front observation window; 31, premixed fuel gas delivery pipeline; 32, penetration part; 33, exhaust pipeline; 34, flue gas collection and delivery pipe; 35, back observation window; 36, explosion-proof safety valve; 37, high-reflectivity optical lens group; 38, flue gas collection module; 39, flue gas collection mobile module; 40, guide rail; 41, slit burner base; 42, burner body; 43, T-shaped flat plate slit assembly; 44, servo-driven flat plate displacement mechanism; 45, carbon-silicon electric heating rod; 46, high-transmittance quartz plate; 47, T-shaped alloy flat plate; 48, high-frequency ignition unit; 49, high-temperature refractory ceramic plate; 50, burner K-type thermocouple; 51, burner heat preservation body; 52, pipeline heat preservation heating belt; 53, burner nozzle; 54, power supply and signal control circuit; 55, burner spout; 56, flat plate linear slide rail; 57, high-frequency response piezoelectric sensor; 58, flat plate K-type thermocouple; 59, stepping servo motor; 60, displacement sensor; 61, mobile platform; 62, flue gas collection telescopic spring pipe; 63, T-shaped ceramic flue gas collection pipe. DETAILED DESCRIPTION

[0063] In the experimental system and method for liquid fuel high-pressure combustion flame and wall interaction provided by the embodiment of the application, the pressure-controllable combustion reaction cavity is used to simulate the internal working condition of an engine under high pressure, the servo-driven flat plate displacement mechanism is used to change the collision distance of the flame and the plate, the mass flow controller is used to control the equivalence ratio, the electric heating device is used to control the temperature, the wall fixed material can be replaced, the flue gas analyzer is used to analyze the combustion products, the micro variables and change rules in the interaction process of the flame and the wall are simulated, and the research on the physical and chemical mechanism of the flame-wall combustion process is realized.

[0064] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0065] Example 1

[0066] This embodiment provides an experimental system for the interaction between a liquid fuel high-pressure combustion flame and a wall surface. Figures 1 to 4 As shown, it includes a pressurization module, a fuel atomization and gasification module, a pressure-controlled combustion reaction chamber 1, a T-shaped flat plate slot burner assembly 25, a distributed temperature monitoring system, an optical diagnostic system, a pressure balance emission module, a flue gas real-time analysis module and a data integration and interaction system; the pressurization module is respectively connected to the pressure-controlled combustion reaction chamber 1 and the fuel atomization and gasification module, and the fuel atomization and gasification module is connected to the pressure-controlled combustion reaction chamber 1; the T-shaped flat plate slot burner assembly 25 is arranged in the pressure-controlled combustion reaction chamber 1 to simulate the collision process between the flame inside the engine and the wall; the distributed temperature monitoring system collects the wall temperature of the T-shaped flat plate slot burner assembly 25 and the preheating temperature of the fuel delivery pipeline in real time The optical diagnostic system collects image information of the interaction process between the flame and the wall of the T-shaped flat-plate slit burner assembly 25 during high-temperature combustion, and transmits the processed data signal to the pressure balance emission module of the data integration and interaction system to ensure pressure stability during the experiment. The flue gas real-time analysis module collects and analyzes the combustion products of the pressure-controlled combustion reaction chamber 1, and transmits the processed data signal to the data integration and interaction system. The data integration and interaction system processes and interacts with data from sensors and equipment of the pressurization module, fuel atomization and gasification module, distributed temperature monitoring system, optical diagnostic system and flue gas real-time analysis module.

[0067] In this embodiment, under the control of the data integration and interaction system, liquid fuel and air are converted into gaseous fuel required for the experiment through the pressurization module and the fuel atomization and gasification module, and transported to the T-shaped flat-plate slit burner assembly 25 to ignite and simulate the collision process between the flame inside the engine and the wall; the pressure-controllable combustion reaction chamber 1, the pressurization module, the pressure balance exhaust module, and the distributed temperature monitoring system are used to ensure the controllability of the experimental conditions; the optical diagnostic system is used to collect image information of the interaction process between the flame and the wall during high-temperature combustion; the flue gas real-time analysis module collects and analyzes the combustion products; this system provides experimental personnel with visual experimental data, reveals the physical and chemical interaction mechanism between the gas phase flame and the solid phase wall, and provides corresponding reference for the improvement of the engine's efficient and clean combustion technology and structural optimization.

[0068] Example 2

[0069] On the basis of the embodiment one, the T-shaped flat slit burner assembly 25 of the present embodiment comprises a slit burner base 41, a burner body 42, a T-shaped flat slit assembly 43, and a servo-driven flat displacement mechanism 44. The slit burner base 41 comprises a steel platform frame structure, and a high-temperature refractory ceramic plate 49 is arranged on the top of the slit burner base 41 to prevent air entrainment at the bottom from causing interference. The burner body 42 is installed below the slit burner base 41, the T-shaped flat slit assembly 43 is installed on the flat linear slide rail 56 of the slit burner base 41, and the servo-driven flat displacement mechanism 44 is installed on the steel frame platform at the rear of the slit burner base 41.

[0070] The burner body 42 comprises a burner insulation body 51, a high-frequency ignition unit 48, and a burner nozzle 53. The burner insulation body 51 is composed of an insulation material, an electric heating wire, and a burner K-type thermocouple 50, and the burner is connected with a premixed fuel gas delivery pipeline 31. The burner K-type thermocouple 50 is arranged on both sides of the burner insulation body 51. The burner nozzle 53 is arranged above the burner insulation body 51, the burner nozzle 55 has a rectangular structure with a length of 15 mm and a width of 1 mm, the top surface of the burner nozzle 55 is flush with the surface of the high-temperature refractory ceramic plate 49, and the high-frequency ignition unit 48 is arranged on the side of the burner nozzle 55. The bottom line penetrates the cabin piece 32 to be connected with the external multi-channel data acquisition module 21, and the PC computer 23 is used to control the high-frequency ignition unit 48 to generate an electric spark ignition. The fuel gas after heating, gasification, and premixing enters the burner insulation body 51 through the premixed fuel gas delivery pipeline 31, and is finally sprayed out of the burner nozzle 55 at the top of the burner nozzle 53 and ignited by the high-frequency ignition unit 48 to generate a flame parallel to the T-shaped alloy flat plate 47.

[0071] The servo-driven flat displacement mechanism 44 is provided with a step servo motor 59 for driving the rotation of the screw rod, and a displacement sensor 60 and a moving platform 61 are arranged on the servo-driven flat displacement mechanism 44, so that the distance data between the plates can be directly read on the PC computer. When the step servo motor 59 drives the rotation of the left and right screw rods, the two moving platforms 61 can simultaneously displace to the center, so as to adjust the slit distance between the plates, and the adjustment accuracy is ±0.01 mm. The extinction distance of the general flame is much larger than this accuracy, which meets the accuracy requirement of the experiment. The T-shaped structure of the T-shaped alloy flat plate 47 increases the heat storage volume of the flat plate, which is beneficial to reduce the fluctuation of the wall temperature and reserve the stroke for the adjustment of the slit distance. In addition, the outer side of the T-shaped alloy flat plate 47 can be covered with insulation cotton to insulate the flat plate and reduce the heat loss in the experiment.

[0072] The T-shaped flat plate slit assembly 43 includes a carbon silicon electric heating rod 45, a high-transmittance quartz plate 46, a T-shaped alloy flat plate 47, a flat plate K-type thermocouple 58 and a flat plate linear slide 56; the carbon silicon electric heating rod 45 is vertically inserted into the T-shaped alloy flat plate 47, and a temperature measuring hole is opened on the side of the T-shaped alloy flat plate 47 to install the flat plate K-type thermocouple 58, which is used to measure the temperature change and heat flux of the wall and the near-wall area during the interaction between the flame and the wall; the two parallel and symmetrically placed T-shaped alloy flat plates 47 are fixed on the servo-driven flat plate by positioning screws. On the two movable platforms 61 of the plate displacement mechanism 44, two high-transmittance quartz plates 46 clamp the T-shaped alloy flat plate 47 to form a slit combustion channel; the flat linear slide 56 is fixedly installed on the slit burner base 41 and docked with the T-shaped alloy flat plate 47. Reducing the weight of the flat plate will increase the resistance to movement; the flat wall of the T-shaped alloy flat plate 47 is a replaceable wall design, and the rectangular thin steel sheet is fixed to the wall by the countersunk nuts at the four corners, so that experiments can be carried out on the interaction process between different wall coatings or different wall materials and flames.

[0073] Example 3

[0074] Based on Example 1, the pressurization module of this embodiment includes an air compressor 10, an air storage tank 7, a liquid fuel storage tank 15, a fuel booster pump 14, an air high-pressure storage tank 16 and an air booster pump 17. The air compressor 10 compresses the air and stores it in the air storage tank 7. The fuel booster pump 14 and the air booster pump 17 respectively pressurize the liquid fuel and air in the liquid fuel storage tank 15 and the air high-pressure storage tank 16 to the pressure required for the experiment.

[0075] Example 4

[0076] On the basis of the third embodiment, the fuel atomization and gasification module of the present embodiment comprises a constant flow pump 12, an electrically controlled fuel gasification electric heater 11, a first mass flow controller 181, a second mass flow controller 182 and a fuel premixing tank 19. Liquid fuel is pressurized to the required experimental pressure, then passes through the delivery pipeline equipped with a fuel pressure gauge 131 through the constant flow pump 12. The output constant flow liquid fuel enters the electrically controlled fuel gasification electric heater 11, is heated and fully gasified in the electric heater. All pipelines thereafter are heat-insulated pipelines wrapped with heat-insulating material and wrapped with pipeline heat-insulating heating belts 52 to prevent the gasified fuel from being cooled and liquefied during delivery, then passes through the first mass flow controller 181. Air is pressurized to the required experimental pressure, then passes through the stainless steel delivery pipeline equipped with an air pressure gauge 132 into the second mass flow controller 182. The output ends of the first mass flow controller 181 and the second mass flow controller 182 are connected to the fuel premixing tank 19. The control signals and data of the mass flow controllers are transmitted to the multi-channel data acquisition module 21. By controlling the mass flow of fuel and air, the equivalence ratio of the experiment is controllable. A one-way valve 20 is installed on the heat-insulated delivery pipeline after the fuel premixing tank 19 and is connected to the input end of the burner.

[0077] Example Five

[0078] On the basis of Example 4, the pressure-controlled combustion reaction chamber 1 of this embodiment includes a cylinder 28, which is used to provide the specific pressure and environment required for the experiment. The combustion reaction chamber body is composed of a special stainless steel cylinder that can withstand high pressure. Since fuel is continuously charged and burned during the experiment, this will inevitably lead to pressure fluctuations in the entire pressure-controlled combustion reaction chamber 1, causing changes in experimental conditions. In order to avoid this problem, on the one hand, the burner flow rate is very small, and on the other hand, a larger combustion chamber size is selected to dilute the pressure fluctuations that may occur during the experiment; the bottom of the combustion chamber is an integrated structure, and a premixed fuel gas delivery pipeline 31 is welded at the bottom. In addition, power supplies and signal control lines 54 such as thermocouples, servo motors, and sensors are connected to external equipment through the through-chamber component 32, and a sealing method is adopted. The front and rear sides and the top of the cylinder 28 are respectively provided with a front observation window 30, a back observation window 35 and a top observation window 26 opened by flanges. The middle of the flange is an observation window made of tempered glass, which is convenient for observing the interaction process between the flame and the T-shaped alloy plate 47 under the high-temperature combustion of the experimental fuel. At the same time, the top observation window 26 is also used for the injection of the pulse laser of the Nd:YAG laser generator 9. The top of the cylinder 28 is installed with a reaction chamber pressure gauge 27 and an explosion-proof safety valve 36; the range of the reaction chamber pressure gauge 27 is -0.1 to 25 MPa. At present, the actual maximum working combustion pressure of diesel engine combustion chambers at home and abroad is usually between 6 MPa and 15 MPa, and the supercharged diesel engine generally reaches more than 13 MPa, which can meet the experimental needs. The reaction chamber pressure gauge 27 allows the experimenter to directly observe the physical environment of the air pressure in the cylinder 28; the explosion-proof safety valve 36 can discharge gas when the pressure in the cylinder 28 is too high, thereby improving the safety of the experiment; the reaction chamber pressure supply pipe 29, the exhaust pipe 33 and the flue gas collection and delivery pipe 34 are welded on the sides of the cylinder 28 respectively. After the air is output from the air storage tank 7, it enters the cylinder 28 through the reaction chamber pressure supply pipe 29 equipped with the third solenoid valve 303. The lower part of the cylinder 28 is provided with a premixed fuel gas delivery pipe 31 and a through-cabin part 32 used as a channel for the power supply and signal control circuit 54; the pipe surface of the premixed fuel gas delivery pipe 31 is wrapped with a pipe insulation heating belt 52.

[0079] Example 6

[0080] On the basis of example five, the high-frequency response piezoelectric sensor 57 is also installed on the column of the servo-driven flat plate displacement mechanism 44 of the present embodiment; the high-frequency response piezoelectric sensor 57 is connected through the multi-channel data acquisition module 21 and the data integration and interaction system, and real-time monitoring of the pressure in the pressure controllable combustion reaction cavity 1 is performed; when the compressed air in the air storage tank 7 is introduced into the pressure controllable combustion reaction cavity 1 until the experimental required pressure value is reached, simultaneously, the heating devices in each part are started, and after reaching the preset temperature, the liquid fuel-air is introduced, the premixed gas after gasification is sprayed from the burner nozzle 53 between the slits, and at the same time, the high-frequency ignition unit 48 is used to ignite the fuel premixed gas. The experimental system has two sets of detection equipment, which need to be separated for experiment when working. The optical diagnosis system for flame shape and wall interaction process: open the pressure balance discharge module, the PID electromagnetic valve continuously bleeds, and the reaction cavity pressure gauge 27 or the high-frequency response piezoelectric sensor 57 pressure signal on the top of the pressure controllable combustion reaction cavity 1 is observed again, the cavity pressure is adjusted by adjusting the power of the air compressor 10 and the electromagnetic valve, and after waiting for the state to be stable, the optical diagnosis system and the distributed temperature monitoring system are used to record the interaction of the flame and the wall. The flue gas analysis system for combustion products: close the pressure balance discharge module, use the flue gas collection mobile module 39 to extend the specially designed T-shaped ceramic flue gas collection pipe 63 into the slits at different positions to collect flue gas, and introduce the external online flue gas analyzer 2 to analyze the combustion products.

[0081] Example seven

[0082] On the basis of example six, the optical diagnosis system of the present embodiment includes an ICCD camera 5 and an OH-PLIF planar laser-induced fluorescence system; the OH-PLIF planar laser-induced fluorescence system includes a Nd:YAG laser generator 9, a dye laser 8, a sheet light shaping assembly 6, and a high reflectivity optical lens group 37; the Nd:YAG laser generator 9 can excite pulsed laser of set wavelength, introduce the pulsed laser into the dye laser 8 to generate dye laser of specific wavelength required by the experiment, and convert the dye laser into about 1.5 mm thick sheet light after passing through the sheet light shaping assembly 6. The sheet light shaping assembly 6 is used to adjust the irradiation width and focal length (divergence and convergence) of the laser, and then the high reflectivity optical lens group 37 is used to vertically cut the sheet light to the slits; by using the horizontally placed ICCD camera 5 with an intensifier, the back observation window 35 on the back of the pressure controllable combustion reaction cavity 1 is observed, the combustion flame process shape of the flame and wall interaction is photographed, the free radical fluorescence signal can also be captured, the fluorescence signal intensity distribution in the flame is recorded, and the concentration of the gas phase OH free radical is characterized. The lens of the used ICCD camera 5 is a UV lens with a bandwidth filter, which can filter the flame self-luminous light, scattered / reflected light of the same frequency of the laser, and other factors such as stray light sources in the experimental environment, and at the same time, in order to obtain larger magnification, a skin cavity is installed in front of the lens.

[0083] Example Eight

[0084] On the basis of example six, the flue gas real-time analysis module of the present embodiment includes online flue gas analyzer 2, flue gas collection and delivery pipe 34, flue gas collection module 38, flue gas collection mobile module 39, guide rail 40, flue gas collection telescopic spring pipe 62 and T-shaped ceramic flue gas collection pipe 63, the T-shaped ceramic flue gas collection pipe 63 is fixed on the flue gas collection module 38, the flue gas collection telescopic spring pipe 62 is connected with the T-shaped ceramic flue gas collection pipe 63 through the flue gas collection module 38; the slide rail of the flue gas collection module 38 is installed on the flue gas collection mobile module 39 at both ends, the guide rail 40 is fixedly installed on the pressure controllable combustion reaction chamber 1 at both ends; the flue gas collection telescopic spring pipe 62 is connected with the flue gas collection and delivery pipe 34, the flue gas collection and delivery pipe 34 is connected with the online flue gas analyzer 2 after passing through the first electromagnetic valve 301. The module also includes an alarm that detects the concentration of combustible gas in the air and alarms when it exceeds the limit to prevent deflagration accidents. The range of the online flue gas analyzer 2 is 0-2000 ppm, the combustion product information is analyzed, and the data signal is transmitted to the data integration and interaction system computer to generate temperature-product concentration, slit spacing-product concentration, etc. two-dimensional coordinate system images.

[0085] Example Nine

[0086] On the basis of example five, the pressure balance exhaust module of the present embodiment is additionally provided with a second electromagnetic valve 302 and a pressure reducing valve 4 on the exhaust pipe 33; under normal working conditions, the flue gas will be automatically discharged under pressurized experimental conditions. The exhaust and flue gas analysis pipes are independently designed and do not interfere with each other.

[0087] Example Ten

[0088] On the basis of embodiment two, the distributed temperature monitoring system of the present embodiment comprises a temperature controller 22 and a multi-channel temperature acquisition instrument 24; the temperature controller 22 is electrically connected with the carbon-silicon electric heating rod 45; the multi-channel temperature acquisition instrument 24 is electrically connected with the flat plate K-type thermocouple 58 and the burner K-type thermocouple 50. The T-type alloy flat plate 47 is provided with a hole for inserting the carbon-silicon electric heating rod 45, which is used for heating the wall surface; the outer side of the T-type alloy flat plate 47 is uniformly provided with a temperature measuring hole for inserting the burner K-type thermocouple 50, the depth of the temperature measuring hole is 2mm to the combustion surface, the multi-channel temperature acquisition instrument 24 collects the temperature signal of the flat plate K-type thermocouple 58, and then transmits the temperature data signal to the multi-channel data acquisition module 21, and transmits the processed signal to the PC terminal computer 23 for storage and visualization; after the experimental personnel obtain the temperature data, they send control commands to the temperature controller 22 according to the experimental conditions, adjust the electric heating power of the carbon-silicon electric heating rod 45, realize the controllable wall surface temperature, and realize the controllable wall surface temperature; the burner K-type thermocouple 50 is also arranged on the burner heat preservation body 51 to monitor the fuel temperature, judge whether the gasified fuel is liquefied, and control the heating power of the fuel atomization and gasification module by the data integration and interaction system.

[0089] In the experiment, the multi-channel temperature acquisition instrument 24 collects the temperature data of the flat plate K-type thermocouple 58, and then transmits to the multi-channel data acquisition module 21 and the PC terminal computer 23, generates available data and generates a two-dimensional coordinate system about the wall surface temperature image, and then uses the PC terminal computer 23 to send control commands to the temperature controller 22 for timely adjustment of the power of the carbon-silicon electric heating rod 45 to realize the monitoring and control of the wall surface temperature; the purpose of heating and temperature control of the wall surface is that on the one hand, the high-temperature wall surface has a flame stabilizing effect on the flame, and by changing the premixed gas flow rate, equivalence ratio, pressure, initial temperature and the like, the flame is finally stabilized at different positions of the channel; on the other hand, the initial state temperature field and the thermal boundary field are fixed, which is convenient for controlling the experimental variables. In addition, in order to realize more stable control of the wall temperature, the outer side of the flat plate is clamped with heat preservation cotton to reduce the loss of heat. The lines of the carbon-silicon electric heating rod 45 and the flat plate K-type thermocouple 58 are connected with external equipment and systems through the bottom of the combustion chamber. Because the liquid fuel used in the experiment is liquefied again in the conveying way after being heated and gasified on the wall surface, the whole pipeline is wrapped with heat preservation material and electric heating wire, and K-type thermocouples for monitoring the temperature in the pipe are arranged every 30cm.

[0090] Embodiment eleven

[0091] Based on the embodiments one to ten, the data integration and interaction system of the present embodiment comprises a multi-channel data acquisition module 21 based on FPGA, a PC terminal computer 23, various sensors, hardware devices, connecting lines and software parts. The multi-channel data acquisition module 21 is connected with a high-frequency response piezoelectric sensor 57, a first mass flow controller 181, a second mass flow controller 182, a displacement sensor 60, a stepping servo motor 59, a high-frequency ignition unit 48, an electromagnetic valve, a temperature controller 22, a multi-channel temperature acquisition instrument 24, an online flue gas analyzer 2, an electrically controlled fuel gasification electric heater 11 and a flue gas collection mobile module 39 through an RS485 to TTL module. The PC terminal computer 23 is connected with the multi-channel data acquisition module 21 through a USB to TTL module, used for collecting and processing experimental data and real-time controlling the working states of various components to achieve the purpose of controlling variables, realizing the collision process between the flame and the wall surface in the single variable simulation engine. Through the PC terminal computer 23, multiple experimental variables can be conveniently and simply controlled, and the interaction process between the flame and the wall surface can be comprehensively and meticulously studied. At the same time, the data visualization processing is used, so that the data collected by the optical diagnosis system, the distributed temperature monitoring system, the high-frequency response piezoelectric sensor 57 and the mass flow controller 182 can be directly generated into a two-dimensional coordinate system image on the PC terminal computer 23, the microscopic variables and the change law in the interaction process between the flame and the wall surface can be directly and intuitively reflected from the data, and the measured data can provide corresponding reference for the improvement and structure optimization of the engine efficient and clean combustion technology.

[0092] As Figure 5As shown, the working principle of the data integration and interaction system includes: the multi-channel data acquisition module 21 communicates with the sensors and control devices using the RS485 to TTL module for bidirectional communication, and communicates with the PC computer 23 using the USB to TTL module for bidirectional communication; the multi-channel data acquisition module 21 continuously sends reading instructions to the sensors and devices through the communication protocol to obtain raw data and perform function conversion processing, etc., to generate twin data that can be directly read by the PC end, and upload the twin data to the EMQX server through WIFI communication technology. EMQX is an open source distributed Internet of Things message server; a MySQL database is established, and a program development tool PyCharm is used to continuously obtain a large amount of sensor data and control parameters in the server by subscribing to the EMQX server, and further uses the ORM programming technology to store the data in the MySQL database, which is convenient for subsequent searching by experimenters. The experiment data received on the PC computer 23 uses Echart to create interactive data visualization charts in the webpage, converts the data into line charts, column charts and numbers for dynamic display, and can intuitively master the running state of the entire experimental system. The experimenters refer to the visual data images on the PC computer 23, manually decide to send control commands to the multi-channel data acquisition module 21 according to specific experimental requirements, and then synchronously control each device.

[0093] The application provides an experimental method for interaction between high-pressure combustion flame of liquid fuel and wall surface, and specifically comprises the following steps:

[0094] S1: adjust the distance between the plates of the T-shaped alloy flat plate 47, control the movement of the moving platform 61 through the stepping servo motor 59, monitor the plate distance through the displacement sensor 60, heat the flat plate through the carbon-silicon electric heating rod 45 after adjusting the plate distance, connect the power supply of the pipeline heat preservation heating belt 52 to preheat the whole pipeline, at the same time, start the air compressor 10 to continuously compress air and store it in the compressed air storage tank 7, and open the third electromagnetic valve 303 to charge the pressure-controllable combustion reaction cavity 1 after sufficient amount of air is compressed.

[0095] S2: the compressed air in the air storage tank 7 is introduced into the pressure-controllable combustion reaction cavity 1 until the required pressure value of the experiment is reached, and the monitoring device pressure is monitored.

[0096] S3: the high-frequency response piezoelectric sensor 57, the flat plate K-type thermocouple 58 and the burner K-type thermocouple 50 are used to monitor the combustion chamber pressure and wall surface temperature, and the fuel delivery pipeline preheating condition in real time until the preset experimental conditions are reached.

[0097] S4: The fuel booster pump 14 and the air booster pump 17 pressurize the liquid fuel in the liquid fuel storage tank 15 and the air in the air high-pressure storage tank 16 to the required pressure for the experiment, respectively; after the liquid fuel is pressurized to the required pressure for the experiment, the liquid fuel is output to the electrically controlled fuel gasification electric heater 11 through a delivery pipeline with a fuel pressure gauge 131 by controlling the volumetric flow rate of the constant flow pump 12, and the constant-flow liquid fuel is heated and fully gasified; after the liquid fuel is gasified, the liquid fuel is delivered to the first mass flow controller 181 through an insulated stainless steel delivery pipeline; after the air is pressurized to the required pressure for the experiment, the air is delivered to the second mass flow controller 182 through a stainless steel delivery pipeline with an air pressure gauge 132; after the fuel and the air are controlled by the first mass flow controller 181 and the second mass flow controller 182 to control the mass flow equivalent ratio, the fuel and the air enter the fuel premixing tank 19, and the gasified premixed gas is delivered to the burner body 42; the premixed gas is sprayed from the burner nozzle 53 in the combustion channel, and the high-frequency ignition unit 48 is used to ignite the premixed gas fuel.

[0098] S5: The fuel gas generation device supplies gas to the burner body 42, the high-frequency ignition unit 48 is used to ignite the premixed gas fuel, the second electromagnetic valve 302 is opened, and whether the pressure in the combustion chamber fluctuates is observed to determine the valve opening degree; after the state is stable and reaches the experimental standard, the flame and the wall surface interaction process are recorded by the optical diagnosis system and the distributed temperature monitoring system;

[0099] S6: After the optical experimental data collection is completed, the flue gas collection and movement module 39 is started to move to the center of the T-shaped flat plate slit assembly 43, the T-shaped ceramic flue gas collection pipe 63 is inserted into the combustion cavity to collect the combustion product gas, and the combustion product gas is delivered to the external online flue gas analyzer 2 for combustion product analysis, and finally discharged to the outside.

[0100] In summary, the experimental system and method for liquid fuel high-pressure combustion flame-wall interaction provided by the application simulate the in-cylinder flame-wall interaction process under high-pressure working conditions in the engine, directly reflect the change law of the micro-variable in the flame-wall interaction process, and realize in-depth research on the flame-wall combustion process.

Claims

1. Experimental system for interaction between liquid fuel high-pressure combustion flame and wall surface, characterized by: It includes a pressurizing module, a fuel atomization and gasification module, a pressure-controlled combustion reaction chamber (1), a T-shaped flat plate slot burner assembly (25), a distributed temperature monitoring system, an optical diagnostic system, a pressure balance emission module, a flue gas real-time analysis module, and a data integration and interaction system; The pressurizing module comprises: A pressure supply unit connected to the pressure-controllable combustion reaction chamber (1) via a high-pressure pipeline; The fuel boosting unit and the air boosting unit are both connected to the fuel atomization and gasification module through high-pressure pipelines; The fuel atomization and gasification module is connected to the pressure-controllable combustion reaction chamber (1) via a heat-insulating delivery pipe; The T-shaped flat plate slot burner assembly (25) is arranged in a pressure-controllable combustion reaction chamber (1) and is used to simulate the dynamic interaction process between the flame and the wall under the working condition of the internal combustion engine. The T-shaped flat plate slot burner assembly (25) includes a slot burner base (41), a burner body (42), a T-shaped flat plate slot assembly (43) and a servo-driven flat plate displacement mechanism (44). The burner body (42) is arranged below the slot burner base (41). The burner body (42) is connected to the fuel atomization and gasification module. The T-shaped flat plate slot assembly (43) is arranged above the slot burner base (41). The servo-driven flat plate displacement mechanism (44) is arranged on a steel frame behind the slot burner base (41). A high-frequency response piezoelectric sensor (57) is also arranged on the steel frame column of the servo-driven flat plate displacement mechanism (44). The distributed temperature monitoring system collects the wall temperature of the T-shaped flat plate slot burner assembly (25) and the thermal state parameters of the fuel delivery pipeline in real time, and transmits them to the data integration and interaction system for processing; The optical diagnostic system collects transient images and free radical distribution information of the flame-wall interaction process of the T-shaped flat plate slit assembly (43) during high-temperature combustion, and transmits the images to the data integration and interaction system for processing; The pressure balance discharge module is arranged on the pressure-controllable combustion reaction chamber (1) to maintain the dynamic pressure balance of the pressure-controllable combustion reaction chamber (1); The flue gas real-time analysis module collects and analyzes the combustion products of the pressure-controlled combustion reaction chamber (1), and transmits the processed data signals to the data integration and interaction system; The data integration and interaction system processes and interacts with data from sensors and devices of the pressurization module, fuel atomization and gasification module, distributed temperature monitoring system, optical diagnostic system and flue gas real-time analysis module.

2. The experimental system for interaction between liquid fuel high-pressure combustion flame and wall according to claim 1, characterized in that: The slot burner base (41) is a frame structure, and a high-temperature refractory ceramic plate (49) is provided on the top of the slot burner base (41); The burner body (42) includes a burner insulation body (51), a high-frequency ignition unit (48) and a burner nozzle (53), the burner insulation body (51) is fixedly installed below the slit burner base (41), the burner insulation body (51) includes insulation material, an electric heating wire and a burner K-type thermocouple (50), the burner insulation body (51) is connected to the air inlet end of the premixed fuel gas delivery pipeline (31), the burner K-type thermocouple (50) is inserted on both sides of the burner insulation body (51), the burner nozzle (53) is arranged above the burner insulation body (51), the top of the burner nozzle (53) is a burner nozzle (55), the top surface of the burner nozzle (55) is flush with the surface of the high-temperature refractory ceramic plate (49), and the high-frequency ignition unit (48) is arranged on the side of the burner nozzle; A stepping servo motor (59) for driving the left and right screw rods of the servo-driven flat plate displacement mechanism (44) is provided on one side of the servo-driven flat plate displacement mechanism (44); a movable platform (61) is movably mounted on the servo-driven flat plate displacement mechanism (44); and a displacement sensor (60) is mounted on the servo-driven flat plate displacement mechanism (44); The T-shaped flat plate slit assembly (43) comprises a carbon silicon electric heating rod (45), a high-transmittance quartz plate (46), two parallel T-shaped alloy flat plates (47) with nitrided surfaces, a flat linear slide rail (56) and a flat plate K-type thermocouple (58); the carbon silicon electric heating rod (45) is vertically inserted into the T-shaped alloy flat plate (47), a temperature measuring hole is provided on the outer side of the T-shaped alloy flat plate (47), the flat plate K-type thermocouple (58) is arranged in the temperature measuring hole, and the two T-shaped alloy flat plates (47) are fixed respectively. On the two movable platforms (61) of the servo-driven flat plate displacement mechanism (44), the two T-shaped alloy flat plates (47) are placed in parallel and symmetrically, the high-transmittance quartz plate (46) is fixed above the slit burner base (41), the two T-shaped alloy flat plates (47) and the two high-transmittance quartz plates (46) constitute a combustion channel, the flat plate linear slide (56) is fixedly installed on the top of the slit burner base (41), and the T-shaped alloy flat plate (47) is movably installed on the flat plate linear slide (56).

3. The experimental system for interaction between liquid fuel high-pressure combustion flame and wall according to claim 2, characterized in that: The pressure supply unit of the pressurizing module includes an air compressor (10) and an air storage tank (7); the fuel boosting unit of the pressurizing module includes a liquid fuel storage tank (15) and a fuel boosting pump (14); the air boosting unit of the pressurizing module includes an air high-pressure storage tank (16) and an air boosting pump (17); The output end of the air compressor (10) is connected to the input end of the air storage tank (7) via a pipeline, the output end of the air storage tank (7) is connected to the pressure-controlled combustion reaction chamber (1) via a pipeline, the output end of the liquid fuel storage tank (15) is connected to the input end of the fuel boosting pump (14) via a pipeline, and the output end of the air high-pressure storage tank (16) is connected to the input end of the air boosting pump (17) via a pipeline; The fuel atomization and gasification module includes: A fuel pretreatment unit, comprising a PID electronically controlled fuel gasification electric heater (11) and a constant flow pump (12); An equivalence ratio precise control unit comprising a first mass flow controller (181), a second mass flow controller (182) and a fuel premixing tank (19); The output end of the fuel boost pump (14) is connected to the constant flow pump (12), the PID electronically controlled fuel gasification electric heater (11), and the first mass flow controller (181) in sequence through a pipeline. The output end of the air boost pump (17) is connected to the input end of the second mass flow controller (182) through a pipeline. The output ends of the first mass flow controller (181) and the second mass flow controller (182) are both connected to the input end of the fuel premixing tank (19) through a pipeline. The output end of the fuel premixing tank (19) is connected to the pressure-controllable combustion reaction chamber (1) through a pipeline after passing through a one-way valve (20).

4. The experimental system for interaction between liquid fuel high-pressure combustion flame and wall according to claim 3, characterized in that: The pressure-controlled combustion reaction chamber (1) comprises a cylinder (28) made of high-strength pressure-resistant steel. The cylinder (28) is designed with three-way orthogonal observation windows, which include a front observation window (30), a back observation window (35) and a top observation window (26). The front observation window (30), the back observation window (35) and the top observation window (26) are respectively arranged on the front and rear sides and the top of the cylinder (28). The top of the cylinder (28) is provided with a reaction chamber pressure gauge (27) and an explosion-proof safety valve (36). The side of the cylinder (28) is provided with a pressure gauge (27) and an explosion-proof safety valve (36). A reaction chamber pressure supply pipe (29), an exhaust pipe (33) and a flue gas collection and delivery pipe (34) are separately provided. The reaction chamber pressure supply pipe (29) is connected to the third solenoid valve (303) and then connected to the output end of the air storage tank (7). The lower part of the cylinder (28) is provided with a premixed fuel gas delivery pipe (31) and a through-chamber component (32) for the passage of a power supply and a signal control circuit (54). The premixed fuel gas delivery pipe (31) is connected to the fuel premixing tank (19). The pipeline surface of the premixed fuel gas delivery pipe (31) is wrapped with a pipeline heat preservation heating belt (52).

5. The experimental system for interaction between liquid fuel high-pressure combustion flame and wall according to claim 4, characterized in that: The optical diagnostic system comprises: An ICCD camera (5) is arranged directly behind the rear observation window (35) to achieve nanosecond-level time-resolved imaging; A tunable light source system includes an Nd:YAG laser generator (9) and a dye laser (8), wherein the Nd:YAG laser generator (9) can excite a pulsating laser of a set wavelength, and the pulsating laser is introduced into the dye laser (8) to generate a dye laser of a specific wavelength required for the experiment; A planar laser-induced fluorescence system comprises a sheet light shaping component (6) and a high-reflectivity optical lens group (37). The dye laser passes through the sheet light shaping component (6) and is then refracted into a combustion channel by the high-reflectivity optical lens group (37).

6. The experimental system for interaction between liquid fuel high-pressure combustion flame and wall according to claim 5, characterized in that: The real-time flue gas analysis module comprises an online flue gas analyzer (2), a flue gas collection and delivery pipe (34), a flue gas collection module (38), a flue gas collection mobile module (39), a guide rail (40), a flue gas collection telescopic spring tube (62) and a T-shaped ceramic flue gas collection pipe (63), wherein the T-shaped ceramic flue gas collection pipe (63) is fixed on the flue gas collection module (38), the flue gas collection telescopic spring tube (62) is connected to the flue gas collection module (38), the flue gas collection module (38) is fixed to the flue gas collection mobile modules (39) at both ends through a crossbeam, the two ends of the guide rail (40) are fixedly mounted on the pressure-controllable combustion reaction chamber (1), the flue gas collection mobile module (39) is movably mounted on the guide rail (40), the flue gas collection telescopic spring tube (62) is connected to the flue gas collection and delivery pipe (34), and the flue gas collection and delivery pipe (34) is connected to the online flue gas analyzer (2) after being connected to the first solenoid valve (301).

7. The experimental system for interaction between liquid fuel high-pressure combustion flame and wall according to claim 6, characterized in that: The pressure-balanced discharge module comprises a pressure reducing valve (4), which is installed at the air outlet of the exhaust pipe (33). A second solenoid valve (302) is also installed on the exhaust pipe (33). When the pressure of the pressure-controlled combustion reaction chamber (1) exceeds a threshold value, the second solenoid valve (302) opens to release the pressure.

8. The experimental system for interaction between liquid fuel high-pressure combustion flame and wall according to claim 7, characterized in that: The distributed temperature monitoring system includes: A temperature controller (22) is electrically connected to the carbon silicon electric heating rod (45) to achieve temperature control of the carbon silicon electric heating rod (45); A multi-channel temperature acquisition instrument (24) is electrically connected to the flat plate K-type thermocouple (58) and the burner K-type thermocouple (50) to achieve synchronous temperature sampling; Infrared thermal imager, assists in verifying the surface temperature field distribution.

9. The experimental system for interaction between liquid fuel high-pressure combustion flame and wall according to claim 8, characterized in that: The data integration and interaction system includes: A multi-channel data acquisition module (21) transmits data with various devices and sensors via an RS485 to TTL module; The PC computer (23) and the control system are connected to the multi-channel data acquisition module (21) via USB to TTL.

10. An experimental system and method for the interaction between a liquid fuel high-pressure combustion flame and a wall surface using the method of claim 9, characterized in that: The specific steps include: S1: Install the target experimental material plate on the T-shaped alloy plate (47); adjust the distance between the plates: control the movement of the mobile platform (61) through the step servo motor (59), and the displacement sensor (60) monitors the distance between the plates. After adjusting the distance between the plates, start the temperature controller (22) to use the carbon silicon electric heating rod (45) to heat the plate, connect the power supply of the pipeline insulation heating belt (52) to preheat the entire pipeline, and at the same time, start the air compressor (10) to continuously compress the air and store it in the air storage tank (7). After a sufficient amount of air is compressed, open the third solenoid valve (303) to pressurize the pressure-controlled combustion reaction chamber (1), and monitor the pressure of the device until the pressure value required for the experiment is reached; S2: Real-time monitoring of the combustion chamber pressure and wall temperature, as well as the preheating of the fuel delivery pipeline, is performed through a high-frequency response piezoelectric sensor (57), a flat plate K-type thermocouple (58) array, and a burner K-type thermocouple (50) until the experimental preset conditions are reached; S3: The fuel booster pump (14) and the air booster pump (17) respectively pressurize the liquid fuel and air in the liquid fuel storage tank (15) and the air high-pressure storage tank (16) to the pressure required for the experiment; after the liquid fuel is pressurized to the pressure required for the experiment, it passes through the delivery pipe with a fuel pressure gauge (131) and controls the volume flow through the constant flow pump (12), and the output constant flow liquid fuel enters the electronically controlled fuel vaporization electric heater (11) for heating and full vaporization. After vaporization, the liquid fuel enters the first mass flow controller (181) through the heat-insulated delivery pipe; after the air is pressurized to the pressure required for the experiment, it enters the second mass flow controller (182) through the delivery pipe with an air pressure gauge (132); the constant flow pump (12) and the mass flow meter realize precise control of the equivalence ratio; the air enters the fuel premixing tank (19) to realize full mixing of fuel / air, and the premixed gas fuel is delivered to the burner body (42) and ejected from the burner nozzle (53) in the combustion channel, and the high-frequency ignition unit (48) ignites the fuel premixed gas at the same time; S4: Open the second solenoid valve (302) and observe whether the pressure in the combustion chamber fluctuates. After the state stabilizes and reaches the experimental standard, high-speed photography is used to synchronously record the flame development process, a planar laser-induced fluorescence system captures the two-dimensional distribution of free radicals, and a distributed temperature monitoring system records the process temperature. S5: After completing the optical experimental data collection, the smoke collection mobile module (39) is started and moved to the center of the adjustable-pitch T-shaped flat plate slit (43), and the T-shaped ceramic smoke collection tube (63) is extended into the combustion chamber to collect the combustion product gas, and the combustion product gas is transported to the external online smoke analyzer (2) for combustion product analysis, and finally discharged to the outside; S6: Data processing, the multi-channel data acquisition module (21) acquires the raw data, transmits it to the PC (23) to generate data packets, and performs data visualization processing.

Images