Spark plug calorific value measuring system and method for controllable activation thermal atmosphere combustor

Abstract

The invention relates to a spark plug calorific value measuring system and method for a controllable activation thermal atmosphere combustor, and the system comprises a combustion assembly which comprises a controllable thermal atmosphere combustor; the testing section comprises a high-temperature-resistant testing pipeline which is vertically mounted above the combustion assembly; the sparking plug clamping and adjusting assembly is used for installing and fixing the sparking plug and can adjust the insertion depth and the radial position of the sparking plug in the high-temperature-resistant test pipeline; the temperature measuring assembly comprises an infrared thermal imager arranged over against the high-temperature-resistant window and a thermocouple used for monitoring the temperature; the cold air rapid cooling assembly is used for instantaneously spraying cooling air into the test cavity after the heating stage is finished; and the data acquisition and control assembly is used for synchronously controlling the combustor power and the cooling airflow triggering time sequence. Compared with the prior art, the method has the advantages of high simulation authenticity and high measurement accuracy; the test efficiency is high and the cost is low; and the flexibility and the adaptability are high.

Description

Technical Field

[0001] This invention relates to the field of internal combustion engine component testing technology, and in particular to a spark plug calorific value measurement system and method for a controllable activated hot atmosphere burner. Background Technology

[0002] As a key component of the ignition system in spark-ignition engines, the calorific value of spark plugs directly affects ignition performance, combustion stability, and service life. The calorific value of a spark plug is a crucial performance indicator for measuring its heat dissipation capacity, directly impacting engine performance, fuel consumption, and emissions. Excessively high or low calorific values ​​can lead to problems such as pre-ignition, knocking, or carbon buildup. Therefore, accurately assessing the calorific value of spark plugs is of great significance for engine development, matching, and fault diagnosis.

[0003] Currently, mainstream spark plug heat value testing methods (such as ISO 11565, SAE J549, GB T38184-2019, etc.) all require testing on a dedicated standard engine test bench. These methods have limitations such as long testing cycles, high costs, numerous interfering factors, and difficulty in separating the influence of specific variables. Furthermore, these tests consume fuel and generate emissions, failing to meet the requirements for convenient, low-cost, environmentally friendly, accurate, and repeatable spark plug testing.

[0004] Therefore, there is an urgent need in this field for an independent testing platform system for measuring the calorific value of spark plugs that can simulate real engine thermal conditions, has a wide temperature range, broad fuel compatibility, accurate measurement, fast response, and is environmentally friendly, as well as corresponding proprietary testing methods and evaluation indicators.

[0005] Existing methods for simulating spark plug heat value based on independent testing platforms other than engine benches, such as the electric heating method, have fundamental limitations in simulating the real in-cylinder environment of an engine. These methods typically use heating elements such as resistance wires to statically or gradually heat the spark plug, and their heat source is fundamentally different from the dynamic high-temperature gas flow generated by the high-speed, high-pressure combustion of the gas mixture during engine operation. The electric heating method mainly relies on heat conduction and natural convection, and cannot reproduce the intense forced convection heat transfer, severe transient thermal shock, and periodic high-frequency thermal cycling processes within the cylinder. Specifically, its shortcomings are as follows: First, it cannot simulate the direct scouring effect of combustion flames on the spark plug insulator skirt and electrodes, resulting in significant deviations between the thermal boundary conditions and heat transfer coefficients of key spark plug components and actual conditions. Second, it lacks the chemical thermal atmosphere under engine operating conditions, meaning the chemical effects (such as catalytic reactions and corrosion) of active free radicals and intermediate products in high-temperature combustion gases on the spark plug surface are completely ignored. Third, it is difficult to apply the high-frequency, alternating thermomechanical loads specific to the engine, which are key factors affecting spark plug thermal fatigue and sealing performance. Therefore, due to the lack of these core physical and chemical processes, the spark plug calorific value parameters or temperature field data obtained based on such methods (such as the electric heating method) often have poor correlation with the results measured on a real engine test bench, and their accuracy is insufficient. These data can only serve as preliminary references and cannot effectively benchmark the performance prediction of real engine spark plugs. Developing higher-fidelity simulation technologies is therefore urgently needed. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art by providing a spark plug calorific value measurement system for a controllable activated hot atmosphere burner, which has strong simulation realism, high measurement accuracy, high testing efficiency, low cost, and strong flexibility and adaptability.

[0007] The objective of this invention can be achieved through the following technical solutions: The core of this invention lies in employing a controllable activated thermal atmosphere burner. By precisely controlling the flow and pressure of fuel and air, a high-temperature airflow is stably and repeatedly generated in a laboratory environment. This activated thermal atmosphere can realistically reproduce the transient thermal shocks, forced convection heat transfer, and complex chemical environments experienced by spark plugs in actual operation. The system integrates a high-precision temperature sensing system (embedded miniature thermocouples and a high-speed infrared thermal imager) to monitor and record the temperature field of key parts of the spark plug, such as the insulator skirt, center electrode, and side electrodes, in real time and online, thereby accurately obtaining key calorific value parameters such as heat distribution, temperature rise, and cooling rate. The method provided by this invention, through the above system, achieves independent, controllable reproduction and quantitative analysis of the spark plug's working thermal load, ultimately providing an efficient, reliable, and highly data-correlated advanced testing method for spark plug design selection, calorific value calibration, performance optimization, and durability assessment suitable for traditional fuel engines.

[0008] This invention provides a spark plug calorific value measurement system for a controllable activated hot atmosphere burner, comprising: The combustion assembly includes a controllable thermal atmosphere burner for introducing and igniting fuel and combustion-supporting gas to generate a stable and uniform high-temperature gas flow, forming a high-temperature activated thermal atmosphere that simulates the in-cylinder thermal environment of an engine. The high-temperature gas, under the action of a fan, forms a uniform upward hot stream that flows through the spark plug. A circular flange viewing window is welded to the spark plug measurement area. The viewing window glass is preferably high-temperature resistant quartz glass / sapphire, sealed with a metal sealing gasket. During cold / hot tests, its own deformation compensates for the expansion difference between the metal flange and the viewing window. The test section includes a high-temperature resistant test pipe installed vertically above the combustion assembly. The high-temperature resistant test pipe is provided with a high-temperature resistant viewing window to form a core test chamber, allowing high-temperature gas to flow through the spark plug. The spark plug clamping and adjusting assembly is used to install and fix the spark plug, and can adjust the insertion depth and radial position of the spark plug in the high temperature test pipeline to ensure that the insulator skirt, center electrode and side electrode of the spark plug are all in the heat flow in the central area of ​​the high temperature test pipeline. The temperature measurement component includes an infrared thermal imager positioned opposite the high-temperature resistant window and a thermocouple for monitoring temperature. It is used for non-contact measurement of temperature changes of the spark plug during heating and cooling processes; it is used to collect and record two-dimensional temperature distribution data of the spark plug insulator skirt surface and electrodes in real time; the thermocouple can be arranged at key locations as needed to monitor the rise and fall of temperature at specific points on the airflow or spark plug, providing auxiliary data for calculation. The rapid cooling component is used to instantly inject precisely controlled cooling air into the test chamber after the heating phase, simulating the spark plug heat dissipation process during the engine intake stroke. Specifically, a constant temperature air source stabilizes the cooling air temperature at a set value (e.g., 25℃±1℃) through a heat exchanger; a mass flow controller is used to precisely set and maintain the mass flow rate to ensure consistent cooling driving force; and a flow field rectification structure ensures uniform and stable airflow, avoiding local eddies. The data acquisition and control component is used to synchronously control burner power and cooling airflow trigger timing, and to collect and record thermal runoff temperature, spark plug surface temperature, clamping fixture temperature, and cold airflow flow rate and temperature. It integrates a multi-channel data acquisition unit to synchronously receive temperature signals from an infrared thermal imager and thermocouples, and uniformly control burner power and cooling airflow trigger timing, automatically recording temperature-time curves to calculate the spark plug's calorific value parameters and thermal response characteristics.

[0009] Furthermore, the combustion assembly is supplied with a hydrogen-air mixture as fuel, and the heat source temperature can be adjusted by precisely controlling the flow rate and ratio of the fuel and the combustion-supporting gas. Furthermore, the combustion assembly is connected to a cooling water tank via a cooling pipe.

[0010] Furthermore, the spark plug clamping and adjusting assembly adopts a partial fixing method that only clamps the bottom of the spark plug to minimize the impact on the external thermal field, and has axial depth adjustment, radial centering adjustment and rotation around the axis functions. To comprehensively acquire temperature data of spark plugs in different positions, a movable and rotatable multi-stage variable clamp is designed to enable flexible positioning of spark plugs in three-dimensional space and circumferential angles, supporting multi-dimensional thermal state detection.

[0011] Furthermore, the adjusting part and the clamping part of the spark plug clamping and adjusting assembly are connected by a rod-shaped connection, and a high-efficiency heat insulation layer is provided at the connection point to block heat conduction outward along the adjusting rod. This ensures that all the heat from the spark plug is dissipated only through the cooling airflow during the cooling process, ensuring the purity of the heat transfer path and the accuracy of the experimental data.

[0012] Furthermore, the thermocouples in the temperature measurement assembly are arranged at multiple positions within the test chamber to measure the temperature of the thermal flow, the temperature of the cold air, the surface temperature of the spark plug, and the temperature of the clamping fixture. Their purpose is limited to monitoring the airflow temperature and assisting in the calibration and verification of infrared thermal imaging. Furthermore, the rapid cooling assembly for cold air includes a blower, a constant temperature air source, an airflow temperature detector, a mass flow controller, a solenoid valve, and a flow field rectification nozzle. The present invention also provides a method for measuring the calorific value of a spark plug in a controllable activated hot atmosphere burner, comprising the following steps: S1: Installation and Position Calibration: Install the spark plug into the spark plug clamping and adjusting assembly, and adjust its position so that the insulator skirt, center electrode, and side electrode of the spark plug are placed in the center area of ​​the test pipe. It is recommended that the spark plug be installed at a 45-degree angle to the horizontal plane, pointing towards the center of the combustion pipe, and confirm with an infrared thermal imager that the surfaces of the insulator skirt, center electrode, and side electrode of the spark plug are within the glass observation window; S2: Heating stage: Start the controllable hot atmosphere burner and introduce a set flow rate of mixed gas to keep the spark plug continuously heated. At the same time, the data acquisition system records its temperature rise curve. S3: Cooling Stage: When the spark plug temperature reaches the preset simulated peak temperature T max At this time, the fuel and air supply to the burner is cut off, and the rapid cooling component is triggered to inject cooling air into the test pipe. Simultaneously, the decrease in spark plug temperature is continuously recorded until the simulated low temperature boundary T is reached. min The simulated peak temperature T max Based on the spark plug temperature calibration at the engine pre-ignition critical point, the simulated low-temperature boundary T min Based on spark plug temperature calibration during engine intake stroke; S4: Data processing: Analyze the collected temperature-time curves and calculate the heating and cooling times of the spark plugs; S5: Parameter Definition: The standard characteristic cooling time t of the spark plug. s Defined as its temperature from T under standard cooling conditions. max Descending to T min The required duration is used as the calorific value parameter.

[0013] Furthermore, following S5, a calorific value assessment step is included: the measured standard characteristic cooling time t s Substituting into the pre-calibrated conversion model IMEP = f(t) s The predicted IMEP value is calculated, and the heat value characteristics of the spark plug are determined based on the correlation between IMEP and heat value. Furthermore, the cooling air temperature during the cooling stage is stabilized at 25℃±1℃, and the flow rate is controlled at 5~40m / s (± 2%). Compared with the prior art, the present invention has the following advantages: (1) High simulation realism and high measurement accuracy. It can simulate the working environment of spark plugs in real engine cylinders with high fidelity. Traditional methods (such as electric heating) cannot reproduce the dynamic high-temperature gas flow generated by high-speed, high-pressure gas combustion and the resulting transient thermal shock, forced convection heat transfer and complex chemical environment (i.e., "activated thermal atmosphere") during engine combustion. This invention uses a controllable activated thermal atmosphere burner as a heat source, and generates a stable and uniform high-temperature gas flow by precisely controlling the flow rate and ratio of fuel and air. This heat source is the same as the heat source in the real engine cylinder, and can realistically reproduce the direct scouring effect of the combustion flame on the spark plug insulator skirt and electrodes, thereby ensuring that the thermal boundary conditions and heat transfer coefficient of key parts of the spark plug are highly consistent with the actual situation, solving the problem of poor correlation between the measurement data of traditional methods and engine bench data, and significantly improving the accuracy and reliability of the measurement results.

[0014] (2) High testing efficiency and low cost. This invention constructs an independent laboratory testing platform, eliminating the reliance on dedicated standard engine benches. Compared with standard testing methods (such as ISO11565, SAE J549, etc.) that require large engine benches, this system has a shorter testing cycle, while traditional methods are time-consuming. Furthermore, it does not require the operation of large engines, consumes less energy, and does not consume large amounts of fuel, thus producing no pollutant emissions and meeting environmental protection requirements. It has significant advantages in equipment cost, operating cost, and time cost, making high-frequency and rapid testing of spark plug heat values ​​possible.

[0015] (3) High flexibility and adaptability. By adjusting the burner power (temperature) and the flow rate and velocity of the rapid cooling system, the thermal load environment under different engine operating conditions (such as different speeds and loads) can be flexibly simulated, providing convenience for studying the thermal behavior of spark plugs under various boundary conditions. In addition, the spark plug clamping and adjustment mechanism of the system has multi-degree-of-freedom adjustment function, which can be compatible with spark plugs of different fields, different models, various structures and various materials, and has a wide range of applications. Attached Figure Description

[0016] Figure 1 A schematic diagram of a spark plug calorific value measurement system for a controllable activated hot atmosphere burner.

[0017] Reference numerals: 1-Infrared thermal imager, 2-Cooling water tank, 3-Controllable thermal atmosphere burner, 4-Thermocouple, 5-Flame arrester, 6-Solenoid valve, 7-Relay, 8-First pressure sensor, 9-Pressure gauge, 10-Flow meter, 11-Second pressure sensor, 12-Temperature sensor, 13-Pressure reducing valve, 14-Check valve, 15-High temperature resistant window, 16-Spark plug, 17-Data acquisition and control components, 18-Blower. Detailed Implementation

[0018] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Component models, material names, connection structures, control methods, algorithms, and other features not explicitly described in this technical solution are considered common technical features disclosed in the prior art.

[0019] Example 1 (Example 1 and Example 2 have a lot of overlapping content. Please check if there is redundancy and if they need to be merged) This embodiment provides a spark plug calorific value measurement system for a controllable activated hot atmosphere burner, such as... Figure 1 As shown, it includes: The combustion assembly includes a controllable thermal atmosphere burner 3, used to introduce and ignite fuel and combustion-supporting gas to generate a stable and uniform high-temperature gas flow, forming a high-temperature activated thermal atmosphere that simulates the in-cylinder thermal environment of an engine; the high-temperature gas forms a uniform upward hot stream under the action of a fan, flowing through the spark plug 16. A circular flange viewing window is welded to the spark plug measurement area. The viewing window glass is preferably high-temperature resistant quartz glass / sapphire, sealed with a metal sealing gasket, which can compensate for the expansion difference between the metal flange and the lens through its own deformation during cold / hot tests. The test section includes a high-temperature resistant test pipe installed vertically above the combustion assembly. A high-temperature resistant viewing window 15 is provided on the high-temperature resistant test pipe to form a core test chamber, allowing high-temperature gas to flow through the spark plug 16. The spark plug clamping and adjusting assembly is used to install and fix the spark plug 16, and can adjust the insertion depth and radial position of the spark plug 16 in the high temperature test pipe, ensuring that the insulator skirt, center electrode and side electrode of the spark plug 16 are all in the heat flow in the central region of the high temperature test pipe. The temperature measurement component includes an infrared thermal imager 1 positioned facing the high-temperature resistant window 15 and a thermocouple 4 for monitoring temperature. It is used for non-contact measurement of the temperature change of the spark plug during heating and cooling; it is used to collect and record two-dimensional temperature distribution data of the spark plug insulator skirt surface and electrodes in real time; the thermocouple can be arranged at key locations as needed to monitor the rise and fall of the airflow or the temperature of specific points on the spark plug, providing auxiliary data for calculation. The rapid cooling component is used to instantly inject precisely controlled cooling air into the test chamber after the heating phase, simulating the spark plug heat dissipation process during the engine intake stroke. Specifically, a constant temperature air source stabilizes the cooling air temperature at a set value (e.g., 25℃±1℃) through a heat exchanger; a mass flow controller is used to precisely set and maintain the mass flow rate to ensure consistent cooling driving force; and a flow field rectification structure ensures uniform and stable airflow, avoiding local eddies. The data acquisition and control component 17 is used to synchronously control the burner power and cooling airflow triggering sequence, and to collect and record temperature data to calculate the calorific value parameters of the spark plug 16. It integrates a multi-channel data acquisition unit to synchronously receive temperature signals from the infrared thermal imager 1 and the thermocouple 4, and uniformly control the burner power and cooling airflow triggering sequence, automatically recording the temperature-time curve, and then calculating the calorific value parameters and thermal response characteristics of the spark plug 16.

[0020] This embodiment also provides a method for measuring the calorific value of a spark plug in a controllable activated hot atmosphere burner, including the following steps: S1: Installation and position calibration: Install spark plug 16 on spark plug clamping and adjusting assembly, adjust the position so that the ignition end of spark plug 16 is in the center area of ​​test pipeline, and use infrared thermal imager 1 to confirm that the surface of the insulator skirt of spark plug 16 and the electrode are in the glass observation window. S2: Heating stage: Start the controllable thermal atmosphere burner 3, introduce the mixed gas at a set flow rate, so that the spark plug 16 is continuously heated, and the data acquisition system records its temperature rise curve at the same time. S3: Cooling Stage: When the temperature of spark plug 16 reaches the preset simulated peak temperature T max At this time, the fuel and air supply is cut off and the cold air rapid cooling component is triggered to inject cooling air into the test pipe, while the temperature drop of spark plug 16 is continuously recorded until it reaches the simulated low temperature boundary T. min The simulated peak temperature T max Based on the spark plug temperature calibration at the engine pre-ignition critical point, the simulated low-temperature boundary T min Based on spark plug temperature calibration during engine intake stroke; S4: Data processing: Analyze the collected temperature-time curves and calculate the heating and cooling time of spark plug 16; S5: Parameter Definition: Sets the standard characteristic cooling time t of spark plug 16. s Defined as its temperature from T under standard cooling conditions. max Descending to T min The required duration is used as the calorific value parameter.

[0021] Example 2 This embodiment provides a spark plug calorific value measurement system for a controllable activated hot atmosphere burner, such as... Figure 1 As shown, it includes: The combustion assembly includes a controllable thermal atmosphere burner 3, used to introduce and ignite fuel and combustion-supporting gas to generate a stable and uniform high-temperature gas flow, forming a high-temperature activated thermal atmosphere that simulates the in-cylinder thermal environment of an engine; the high-temperature gas forms a uniform upward hot stream under the action of a fan, flowing through the spark plug 16. A circular flange viewing window is welded to the spark plug measurement area. The viewing window glass is preferably high-temperature resistant quartz glass / sapphire, sealed with a metal sealing gasket, which can compensate for the expansion difference between the metal flange and the lens through its own deformation during cold / hot tests. The test section includes a high-temperature resistant test pipe installed vertically above the combustion assembly. A high-temperature resistant viewing window 15 is provided on the high-temperature resistant test pipe to form a core test chamber, allowing high-temperature gas to flow through the spark plug 16. The spark plug clamping and adjusting assembly is used to install and fix the spark plug 16, and can adjust the insertion depth and radial position of the spark plug 16 in the high temperature test pipe, ensuring that the insulator skirt, center electrode and side electrode of the spark plug 16 are all in the heat flow in the central region of the high temperature test pipe. The temperature measurement component includes an infrared thermal imager 1 positioned facing the high-temperature resistant window 15 and a thermocouple 4 for monitoring temperature. It is used for non-contact measurement of the temperature change of the spark plug during heating and cooling; it is used to collect and record two-dimensional temperature distribution data of the spark plug insulator skirt surface and electrodes in real time; the thermocouple can be arranged at key locations as needed to monitor the rise and fall of the airflow or the temperature of specific points on the spark plug, providing auxiliary data for calculation. The rapid cooling component is used to instantly inject precisely controlled cooling air into the test chamber after the heating phase, simulating the spark plug heat dissipation process during the engine intake stroke. Specifically, a constant temperature air source stabilizes the cooling air temperature at a set value (e.g., 25℃±1℃) through a heat exchanger; a mass flow controller is used to precisely set and maintain the mass flow rate to ensure consistent cooling driving force; and a flow field rectification structure ensures uniform and stable airflow, avoiding local eddies. The data acquisition and control component 17 is used to synchronously control the burner power and cooling airflow triggering sequence, and to collect and record temperature data to calculate the calorific value parameters of the spark plug 16. It integrates a multi-channel data acquisition unit to synchronously receive temperature signals from the infrared thermal imager 1 and the thermocouple 4, and uniformly control the burner power and cooling airflow triggering sequence, automatically recording the temperature-time curve, and then calculating the calorific value parameters and thermal response characteristics of the spark plug 16.

[0022] In a specific embodiment, the combustion component is supplied with a hydrogen-air mixture as fuel, and the heat source temperature can be adjusted by precisely controlling the flow rate and ratio of the fuel and the combustion-supporting gas. In a specific embodiment, the combustion assembly is connected to a cooling water tank 2 via a cooling pipe.

[0023] In a specific embodiment, the spark plug clamping and adjusting assembly is made of the same material as the spark plug 16, and adopts a partial fixing method that only clamps the bottom of the spark plug to minimize the impact on the external heat field. It has axial depth adjustment, radial centering adjustment and rotation around the axis functions. To comprehensively acquire temperature data of spark plugs in different positions, a movable and rotatable multi-stage variable clamp is designed to enable flexible positioning of spark plugs in three-dimensional space and circumferential angles, supporting multi-dimensional thermal state detection.

[0024] In a specific embodiment, the adjusting part and the clamping part of the spark plug clamping and adjusting assembly are connected by a rod-shaped connection, and a high-efficiency heat insulation layer is provided at the connection to block heat conduction outward along the adjusting rod. This ensures that all the heat from the spark plug is dissipated only through the cooling airflow during the cooling process, ensuring the purity of the heat transfer path and the accuracy of the experimental data.

[0025] In a specific embodiment, the thermocouples 4 in the temperature measurement assembly are arranged at multiple positions in the test chamber to measure the temperature of the thermal flow, the temperature of the cold air, the surface temperature of the spark plug, and the temperature of the clamping fixture. Their purpose is limited to monitoring the airflow temperature and assisting in the calibration and verification of infrared thermal imaging. In a specific embodiment, the rapid cooling cold air assembly includes a constant temperature air source, a mass flow controller, a solenoid valve 6, and a flow field rectification nozzle. In a specific implementation, a flame arrester 5 is also included, which is located after the solenoid valve 6 for safety protection. When an accidental backfire occurs and the flame propagates in the reverse direction from the burner to the fuel source, the flame arrester 5 can effectively extinguish the flame, prevent the accident from spreading to the upstream fuel supply system, and ensure the safety of equipment and personnel.

[0026] It also includes relay 7, which is used for electrical isolation and power amplification.

[0027] It also includes a first pressure sensor 8 and a second pressure sensor 11. The first pressure sensor 8 is installed on the fuel supply line to monitor the fuel pressure supplied to the burner, and the second pressure sensor 11 is installed on the combustion air or cooling air line to monitor the pressure of the corresponding airflow.

[0028] It also includes pressure gauge 9 and flow meter 10, which measure pressure and gas medium flow rate, respectively.

[0029] It also includes a temperature sensor 12 for measuring the temperature at different key points.

[0030] It also includes a pressure reducing valve 13 and a check valve 14.

[0031] It also includes a blower 18, which provides combustion air to the burner and guides the high-temperature gas to form an upward uniform heat flow.

[0032] This embodiment also provides a method for measuring the calorific value of a spark plug in a controllable activated hot atmosphere burner, including the following steps: S1: Installation and Position Calibration: Install spark plug 16 onto the spark plug clamping and adjusting assembly, adjust the position so that the surface of the insulator skirt and the electrode of spark plug 16 are in the center area of ​​the test pipeline, and confirm that it is located within the glass observation window using infrared thermal imager 1.

[0033] S2: Heating stage: Start the controllable thermal atmosphere burner 3 and introduce hydrogen-air mixture with a set flow rate and ratio to form a stable and uniform high-temperature gas flow, so that the spark plug 16 is continuously heated. At the same time, the data acquisition system records data from the infrared thermal imager and auxiliary thermocouples, fully capturing the dynamic curve of the spark plug temperature rising over time, and monitoring its fluctuations near the target temperature. S3: Cooling Stage: When the temperature of spark plug 16 reaches the preset simulated peak temperature T max At this time, the fuel and air supply is cut off and the cold air rapid cooling component is triggered to inject cooling air into the test pipe, while the temperature drop of spark plug 16 is continuously recorded until it reaches the simulated low temperature boundary T. min The simulated peak temperature T max Based on the spark plug temperature calibration at the engine pre-ignition critical point, the simulated low-temperature boundary T min Calibration is based on spark plug temperature during the engine intake stroke; cooling air temperature is stabilized at 25℃±1℃, and flow rate is controlled at 5~40 m / s (± 2%); specifically, the simulated peak temperature T max = 900℃ (based on spark plug temperature calibration at engine pre-ignition critical point); Simulated low temperature boundary T min = 500℃ (based on spark plug temperature calibration during engine intake stroke).

[0034] S4: Data Processing: Analyze the collected temperature-time curves and calculate the heating and cooling times of spark plug 16; analyze and process the collected temperature-time history curves: calculate the heating time of the spark plug from a certain low temperature characteristic point (e.g., 500℃) to a certain high temperature characteristic point (e.g., 800℃) to characterize its heating rate; calculate the cooling time from a certain high temperature characteristic point (e.g., 900℃) to a certain low temperature characteristic point (e.g., 500℃) to characterize its heat dissipation rate; S5: Parameter Definition: Sets the standard characteristic cooling time t of spark plug 16. s Defined as its temperature from T under standard cooling conditions. max Descending to Tmin The required duration is used as the calorific value parameter.

[0035] In a specific implementation, after S5, a calorific value evaluation step is also included: the measured standard characteristic cooling time t is used to determine the calorific value. s Substituting into the pre-calibrated conversion model IMEP = f(t) s The predicted IMEP value is calculated, and the heat value characteristics of spark plug 16 are determined based on the correlation between IMEP and heat value. The heat value of spark plugs defined in international standards is essentially a comprehensive evaluation of their thermal behavior under continuous engine operation. This standard gradually increases the load on a dedicated engine test bench, bringing the spark plug towards its thermal critical state, and uses the IMEP value measured after 3 minutes of continuous stable operation as the basis for heat value evaluation. The core of this invention lies in moving beyond the traditional steady-state testing framework and instead simulating the transient thermal shock process experienced by the spark plug during a single engine operating cycle. This method defines the temperature boundaries of the test, including a temperature rise peak and a cooling endpoint. The temperature rise peak is set to match the peak temperature reached by the spark plug under critical pre-ignition conditions in actual engine testing; the cooling endpoint is set to match the low temperature boundary reached by the spark plug after the intake stroke in actual engine testing.

[0036] By accurately reproducing the aforementioned temperature boundaries and combining them with precisely controllable cooling medium parameters (such as flow rate, velocity, and temperature), this method can achieve accurate measurement of the single-cycle thermal dynamic behavior of spark plugs and establish new thermal characteristic evaluation indicators accordingly.

[0037] Final definition of calorific value parameter Under the standardized boundary conditions and cooling conditions described above, we define the heat value parameters of the spark plug as follows: Spark plug standard characteristic cooling time (t) s ) is defined as the temperature rise of the spark plug center electrode from the peak temperature (T) under standard cooling conditions. max The temperature naturally decreases to the temperature drop point (T). min The required duration, in seconds (s).

[0038] Physical meaning: ts directly quantifies the absolute heat dissipation rate of the spark plug under simulated engine thermal boundary conditions.

[0039] The smaller the ts value, the stronger the spark plug's heat dissipation capacity and the "cooler" its thermal characteristics.

[0040] The higher the ts value, the weaker the spark plug's heat dissipation capacity and the "hotter" its thermal characteristics.

[0041] A correlation model and benchmarking system can be established between the calorific value of this patent and the calorific value in international standards. 1. Basic data benchmarking: Select a set of standard spark plugs covering cold to hot types as a benchmark.

[0042] 2. Dual-platform testing: On an engine test bench, the rated IMEP value of each standard sample was measured strictly according to SAE J549 standard. On the offline calorimetry measurement system of this patent, the standard characteristic cooling time t of each standard sample was measured under the same cooling conditions. s (The calorific value as defined in this patent). Database formation: Obtaining a set of one-to-one corresponding data pairs: (t) s1 , IMEP1), (t s2 , IMEP2)..., (t sn IMEP n ).

[0043] 3. Data Analysis: Plot the above data on a scatter plot (X-axis is t). s (Y-axis is IMEP). Based on the distribution trend of the data points, t s It is expected that there will be a clear negative correlation with IMEP (i.e., t). s The smaller the value, the faster the heat dissipation; the higher the IMEP value, the "cooler" the spark plug. Determine the optimal fitting curve through linear or nonlinear regression analysis; once a reliable conversion function IMEP = f(t) is obtained... s That is, for any unknown spark plug, you only need to measure its t on your new test bench. s This can be substituted into the model to predict its equivalent engine IMEP value (i.e., the heat value under the engine test platform).

[0044] Components not described in detail in this embodiment are all existing components that can be purchased through public channels.

[0045] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A spark plug calorific value measurement system for a controllable activated hot atmosphere burner, characterized in that, include: Combustion components, including a controllable thermal atmosphere burner (3), are used to introduce fuel and combustion-supporting gas and ignite them to generate a high-temperature gas flow and form a high-temperature activated thermal atmosphere that simulates the in-cylinder thermal environment of an engine. The test section includes a high-temperature test pipe installed vertically above the combustion assembly. A high-temperature test window (15) is provided on the high-temperature test pipe to form a core test chamber, allowing high-temperature gas to flow through the spark plug (16). The spark plug clamping and adjusting assembly is used to install and fix the spark plug (16) and can adjust the insertion depth and radial position of the spark plug (16) in the high temperature test pipe to ensure that the ignition end of the spark plug (16) is in the heat flow in the central area of ​​the high temperature test pipe. The temperature measurement assembly includes an infrared thermal imager (1) arranged facing the high-temperature resistant window (15) and a thermocouple (4) for monitoring temperature, for non-contact measurement of the temperature change of the spark plug during heating and cooling. The rapid cooling component is used to spray cooling air with controlled temperature, flow rate and flow pattern into the test chamber instantaneously after the heating phase ends, in order to simulate the spark plug heat dissipation process during the engine intake stroke. The data acquisition and control component (17) is used to synchronously control the burner power and cooling airflow triggering sequence, and to collect and record temperature data to calculate the calorific value parameters of the spark plug (16).

2. The spark plug calorific value measurement system for a controllable activated thermal atmosphere burner according to claim 1, characterized in that, The combustion assembly is supplied with a hydrogen-air mixture as fuel, and the heat source temperature can be adjusted by controlling the flow rate and ratio of the fuel and the combustion-supporting gas.

3. The spark plug calorific value measurement system for a controllable activated thermal atmosphere burner according to claim 1, characterized in that, The combustion assembly is connected to a cooling water tank (2) via a cooling pipe.

4. The spark plug calorific value measurement system for a controllable activated thermal atmosphere burner according to claim 1, characterized in that, The spark plug clamping and adjusting assembly adopts a partial fixing method that only clamps the bottom of the spark plug, and has axial depth adjustment, radial centering adjustment and rotation around the axis functions.

5. The spark plug calorific value measurement system for a controllable activated thermal atmosphere burner according to claim 1, characterized in that, The spark plug clamping and adjusting assembly is connected to the adjusting part and the clamping part by a rod-shaped connection, and a high-efficiency heat insulation layer is provided at the connection to block heat from being conducted outward along the adjusting rod.

6. The spark plug calorific value measurement system for a controllable activated thermal atmosphere burner according to claim 1, characterized in that, The thermocouples (4) in the temperature measurement assembly are arranged in multiple positions in the test chamber to measure the temperature of the thermal flow, the temperature of the cold air, the surface temperature of the spark plug and the temperature of the clamping fixture. Their purpose is limited to monitoring the airflow temperature and assisting in the calibration and verification of infrared thermal imaging.

7. The spark plug calorific value measurement system for a controllable activated thermal atmosphere burner according to claim 1, characterized in that, The rapid cooling assembly for cold air includes a blower, a constant temperature air source, a mass flow controller, a solenoid valve (6), and a flow field rectification nozzle.

8. A method for measuring the calorific value of a spark plug in a controllable activated thermal atmosphere burner as described in any one of claims 1-7, characterized in that, Includes the following steps: S1: Installation and position calibration: Install the spark plug (16) on the spark plug clamping and adjusting assembly, adjust the position so that the ignition end of the spark plug (16) is in the center area of ​​the test pipeline, and confirm that the surface of the insulator skirt and the electrode of the spark plug (16) are in the glass observation window by using an infrared thermal imager (1). S2: Heating stage: Start the controllable thermal atmosphere burner (3), introduce the mixed gas at a set flow rate, so that the spark plug (16) is continuously heated, and the data acquisition system records its temperature rise curve at the same time. S3: Cooling stage: When the temperature of the spark plug (16) reaches the preset simulated peak temperature Tmax, the fuel and air supply is cut off, and the cold air rapid cooling component is triggered to spray cooling air into the test pipe. At the same time, the process of the spark plug (16) temperature decreasing is continuously recorded until the simulated low temperature boundary Tmin is reached. S4: Data processing: Analyze the collected temperature-time curves and calculate the heating and cooling times of the spark plug (16); S5: Parameter definition: The standard characteristic cooling time ts of the spark plug (16) is defined as the duration required for the temperature to drop from Tmax to Tmin under standard cooling conditions, and is used as the heat value parameter.

9. The method for measuring the calorific value of a spark plug in a controllable activated thermal atmosphere burner according to claim 8, characterized in that, After S5, the heat value evaluation step is also included: the measured standard characteristic cooling time ts is substituted into the pre-calibrated conversion model IMEP = f(ts) to calculate the predicted IMEP value, and the heat value characteristics of the spark plug (16) are determined according to the comparison relationship between IMEP and heat value.

10. The method for measuring the calorific value of a spark plug in a controllable activated thermal atmosphere burner according to claim 8, characterized in that, During the cooling stage, the temperature of the cooling air is kept stable at 25℃±1℃, and the flow rate is controlled at 5~40 m / s (± 2%).

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