Combustion Flame Adjustment Method Based on Gas Valve Matching Control and Gas Valve

Abstract

The present application provides a combustion flame adjustment method and a gas valve based on gas valve matching control, belonging to the field of gas control and combustion optimization. The method includes: determining a first opening degree of the gas valve; determining a first gas flow rate at the combustion outlet based on the first opening degree; calculating an ideal combustion temperature based on the first gas flow rate; outputting a mixed gas corresponding to the first gas flow rate, and burning to generate an initial flame; detecting the inner flame temperature and the outer flame temperature of the initial flame, and determining the inner and outer flame boundaries of the initial flame; determining the proportion of the inner and outer flames in the initial flame based on the inner and outer flame boundaries; calculating the comprehensive real-time temperature of the initial flame based on the proportion and the inner flame temperature and the outer flame temperature; calculating a second opening degree of the proportional solenoid valve based on the difference between the comprehensive real-time temperature and the ideal combustion temperature, and controlling the proportional solenoid valve according to the second opening degree to complete gas output. The present application can solve the problems of complex structure, high cost, and adjustment lag of existing gas valves.

Description

Technical Field

[0001] The present application relates to the technical field of gas control and combustion optimization, and particularly to a combustion flame adjustment method and a gas valve based on gas valve matching control. Background Art

[0002] In the field of modern energy utilization, gas combustion equipment (such as gas stoves, gas boilers, etc.) is widely used in scenarios such as household cooking and industrial heating. The efficient and stable combustion of gas is crucial for energy utilization efficiency, environmental protection, and the safe operation of equipment.

[0003] Currently, in terms of gas combustion control, the existing technologies mainly adjust the gas flow rate and air supply through traditional mechanical control and simple electronic control methods. For example, common gas stoves mostly use manual valves to control the gas flow rate and adjust the air intake through dampers. In some more advanced devices, a simple proportional control method is also adopted, and the gas and air supply amounts are adjusted in a fixed proportion according to the set temperature or firepower level.

[0004] However, there are many problems in the existing technologies. First, the control of the gas and air mixing ratio is not precise enough. Due to the differences in gas components of different gas sources and the changes in the combustion environment (such as air pressure, temperature, etc.), the traditional fixed proportion control method is difficult to adapt to these changes, resulting in the inability of gas and air to always maintain an ideal mixing ratio, thereby affecting the combustion efficiency, causing energy waste, and at the same time, more pollutants (such as carbon monoxide, etc.) may be emitted.

[0005] Secondly, the existing technologies lack real-time and precise monitoring of the flame state. Only relying on simple temperature detection or manual observation of the flame color and other methods, it is impossible to accurately obtain key information such as the inner flame temperature, outer flame temperature, and the boundary between the inner and outer flames of the flame, making it difficult to deeply analyze and optimize the combustion process. For example, it is impossible to adjust the gas and air supply in a timely manner according to the changes in the flame state to achieve the best combustion effect.

[0006] In addition, the existing control technologies have a low level of intelligence and cannot perform adaptive adjustment according to the real-time data during the combustion process. When the gas flow rate, air supply amount, or combustion environment changes, they cannot respond in a timely and accurate manner, making it difficult to meet the modern combustion requirements of high efficiency, energy conservation, and environmental protection. Summary of the Invention

[0007] In view of this, the present application provides a combustion flame adjustment method and a gas valve based on gas valve matching control to solve the problems of complex structure, high cost, and adjustment lag of the existing electromagnetic proportional valves.

[0008] Specifically, the present application is implemented through the following technical solutions:

[0009] The first aspect of the present application provides a combustion flame adjustment method based on gas valve matching control, and the method includes:

[0010] Determine the first opening degree of the gas valve, where the gas valve is jointly controlled by a gas manual valve and a proportional solenoid valve;

[0011] Based on the first opening degree, determine the first gas flow rate at the combustion outlet;

[0012] Calculate the ideal combustion temperature based on the first gas flow rate;

[0013] Output the mixed gas corresponding to the first gas flow rate to generate an initial flame by combustion;

[0014] Detect the inner flame temperature and the outer flame temperature of the initial flame. Taking the detection position corresponding to the inner flame temperature as the starting point and the detection position corresponding to the outer flame temperature as the end point, predict the temperature change path between the starting point and the end point at a preset step length, and determine the inner and outer flame boundaries of the initial flame based on the temperature change path;

[0015] Based on the inner and outer flame boundaries, determine the proportion of the inner and outer flames in the initial flame;

[0016] Calculate the comprehensive real-time temperature of the initial flame based on the proportion, the inner flame temperature, and the outer flame temperature;

[0017] Calculate the second opening degree of the proportional solenoid valve based on the difference between the comprehensive real-time temperature and the ideal combustion temperature, and control the proportional solenoid valve according to the second opening degree to complete gas output.

[0018] The second aspect of the present application provides a gas valve, and the gas valve is applied to the method described in the first aspect.

[0019] The gas valve at least includes a valve body, a gas manual valve, and a proportional solenoid valve; the gas manual valve and the proportional solenoid valve are connected to the same valve port and jointly control the flux of the same valve port;

[0020] The gas manual valve is located below the valve body. The lower block is fixedly connected to the valve body by a thread. An adjusting nut, an adjusting strut, and a seal are sequentially arranged on the lower block. Among them, the seal is fixed on the adjusting strut, the adjusting strut is connected to the adjusting nut by a pin, and the adjusting strut is movably connected to the lower block by a thread;

[0021] The proportional solenoid valve is located above the valve body. The magnetic isolation tube is fixedly connected to the valve body and nested in the coil assembly. The movable iron core, the adjusting spring, and the adjusting screw are stacked in the magnetic isolation tube from top to bottom in sequence; among them, a seal is fixed on the movable iron core, and the seal contacts the gas circulation port above the valve body.

[0022] The combustion flame adjustment method and gas valve provided by this application can, generally speaking, achieve both manual and automatic control of gas combustion by adopting two control means for one valve (including manual control mode and electromagnetic control mode). Automatic control is the main means for daily regulation, while the manual valve is used as a supplement in special cases (no electricity, special application scenarios require the flame to be maintained all the time). Based on these two control modes, by accurately considering the temperature difference between the inner flame and the outer flame of the flame, the accurate real-time combustion temperature of the flame can be determined through the temperature values on an entire path. Then, based on the accurate real-time temperature of the flame, according to the difference between the ideal temperature and the actual temperature of combustion, the opening of the proportional electromagnetic valve is adjusted in coordination, and the manual valve is used to ensure the gas supply in special scenarios. Based on the precise control of the valve in the automatic control mode, the flame of gas combustion is increased, and at the same time, the temperature of the flame is increased, so that the actual combustion temperature can reach the ideal temperature, realizing the optimal combustion control of gas.

[0023] Specifically, by determining the first opening of the gas valve, the first gas flow rate is determined based on the first opening, and then the ideal combustion temperature is calculated according to this flow rate. Using this method to estimate the ideal temperature of the gas provides a precise reference for subsequent combustion control, makes the combustion more complete, improves the combustion efficiency, and reduces the waste of energy. Detect the inner flame temperature and outer flame temperature of the initial flame, determine the inner and outer flame boundaries and proportions, and then calculate the comprehensive real-time temperature. Predict the temperature change path between the starting point and the ending point with a preset step length, and based on this, determine the inner and outer flame boundaries of the initial flame. This method can analyze the structure and characteristics of the flame more accurately, provide a more precise basis for subsequent control, further improve the accuracy of control. This detailed analysis of the flame characteristics helps to more precisely grasp the combustion state and adjust the gas supply according to the actual combustion situation, further improving the combustion efficiency.

[0024] In addition, by accurately calculating the ideal combustion temperature, the comprehensive real-time temperature, and the second opening of the proportional electromagnetic valve, the precise control of the combustion process is achieved. It can quickly and accurately adjust the valve opening according to the actual situation, making the combustion state always close to the ideal state, and improving the accuracy and stability of temperature control. Brief Description of the Drawings

[0025] Figure 1 It is a flowchart of Embodiment 1 of the combustion flame adjustment method based on gas valve matching control provided by this application;

[0026] Figure 2 It is a schematic structural diagram of the gas manual valve of the gas valve provided by this application;

[0027] Figure 3Schematic structural diagram of the proportional solenoid valve of the gas valve provided by this application;

[0028] Description of reference numerals:

[0029] 1 - valve body; 2 - adjusting strut; 3 - seal; 4 - adjusting nut; 5 - lower stop; 6 - first thread and 7 - second thread; 8 - moving iron core; 9 - coil assembly; 10 - adjusting screw; 11 - adjusting spring; 12 - magnetic isolation tube. Detailed implementation manners

[0030] Here, the exemplary embodiments will be described in detail, and the examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementation manners described in the following exemplary embodiments do not represent all the implementation manners consistent with this application.

[0031] The terms used in this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The singular forms "a", "the", and "said" used in this application are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0032] It should be understood that although the terms first, second, third, etc. may be used in this application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "when" or "while" or "in response to determining".

[0033] The following specific embodiments are given to introduce the technical solutions of this application in detail.

[0034] Embodiment 1:

[0035] Figure 1 Flowchart of Embodiment 1 of the combustion flame adjustment method based on gas valve matching control provided by this application. Please refer to Figure 1 , the method provided in this embodiment may include:

[0036] S101. Determine the first opening degree of the gas valve, where the gas valve is jointly controlled by a gas manual valve and a proportional solenoid valve.

[0037] It should be noted that in the gas combustion control system involved in this application, determining the first opening degree of the gas valve is the starting key step of the entire control process. The gas valve consists of a gas manual valve and a proportional solenoid valve to form a control system. The two work together to determine the initial gas supply state, and the accurate determination of the first opening degree is of great significance for the precise control of the subsequent combustion process.

[0038] Among them, the gas manual valve, as a basic control component, has a manual adjustment function and plays a role in providing the basic gas flow in the system. And when there is a power failure or the electronic control module fails, it can serve as an emergency channel to maintain gas supply. The proportional solenoid valve is an electronic control component that can automatically and precisely adjust the opening degree according to signals such as temperature and gas concentration feedback from the system, realizing the dynamic adjustment of gas flow.

[0039] It should be noted that there are various situations for determining the first opening degree of the gas valve:

[0040] ① The gas manual valve is not opened: When the gas manual valve is in the closed state, the first opening degree of the gas valve is completely determined by the proportional solenoid valve. At this time, the proportional solenoid valve determines its own opening degree according to the preset parameters of the system or the control instructions input externally, and then determines the initial gas flow.

[0041] ② The gas manual valve is opened: If the gas manual valve is opened, the first opening degree is the sum of the opening degree of the gas manual valve and the opening degree of the proportional solenoid valve. In this case, the user manually adjusts the gas manual valve to provide a basic opening degree, and at the same time the proportional solenoid valve further adjusts the opening degree according to the system feedback. The two are superimposed to form the final first opening degree. For example, if the user adjusts the gas manual valve to 30% opening degree, and the system controls the proportional solenoid valve to open 15% according to the real-time monitored flame temperature and other information, then the first opening degree of the gas valve at this time is 30% + 15% = 45%.

[0042] ③ The proportional solenoid valve is closed: When the proportional solenoid valve is closed, the first opening degree of the gas valve is solely determined by the gas manual valve. This plays a role in special situations such as power failure or proportional solenoid valve failure to ensure that gas can still be supplied to maintain basic combustion requirements. For example, during a power outage, the user can manually adjust the gas manual valve to open a certain angle (assumed to be 10% opening degree) to ensure that gas can be continuously output to meet emergency use needs.

[0043] In specific implementation, in order to accurately determine the first opening degree, various sensors can be used for real-time monitoring. For example, sensors such as potentiometers or Hall elements are used to detect the physical opening degree of the gas manual valve, and this opening degree value can be accurately characterized in the form of a percentage (such as "30% opening") or an absolute value (such as "rotation angle θ = 45°"). For a proportional electromagnetic valve, its opening degree state can be determined by detecting relevant parameters of its control signal (such as the correspondence between the current magnitude and the opening degree).

[0044] In this way, the opening degree information of the two valves can be obtained quickly and accurately, and then the first opening degree of the gas valve can be determined, providing a reliable data basis for subsequent accurate calculation of the gas flow rate and optimization of the combustion process.

[0045] S102. Determine the first gas flow rate at the combustion outlet based on the first opening degree.

[0046] Determining the first gas flow rate at the combustion outlet based on the first opening degree is a key link in achieving precise combustion control, and its result will directly affect the subsequent calculation of the combustion temperature and the quality of the combustion effect. The adequacy of the mixture of the gas output at the combustion outlet and the oxygen in the air can be used to judge whether the combustion is sufficient. Therefore, the first gas flow rate refers to the gas after the gas output at the combustion outlet is mixed with the air at the combustion outlet and can be directly used for combustion. Specifically, determining the first gas flow rate at the combustion outlet based on the first opening degree includes:

[0047] (1) Calculate the gas flow rate entering the gas valve based on the first opening degree, where the first opening degree is the sum of the opening degree of the gas manual valve and the opening degree of the proportional electromagnetic valve.

[0048] Combined with the above description, the first opening degree is jointly determined by the gas manual valve and the proportional electromagnetic valve, and there are various situations. When the gas manual valve is not opened, the first opening degree completely depends on the opening degree of the proportional electromagnetic valve; if the gas manual valve is opened, the first opening degree is the sum of the two opening degrees; if the proportional electromagnetic valve is closed, the first opening degree is solely determined by the gas manual valve. Preferably, calculating the gas flow rate entering based on the first opening degree includes:

[0049] (i) Determine the shape information of the gas valve.

[0050] The shape of the valve core of the gas valve has an important impact on the relationship between the opening degree and the flow area. Taking the common sector-shaped valve core as an example, the opening degree can be represented by the central angle of the sector notch. For example, 0° represents closed and 90° represents fully open, and its flow area will change linearly with the increase of the central angle. Of course, if the valve core shape is other types, such as circular, square, etc., the relationship between the opening degree and the flow area can be determined by specific calculation methods, such as measuring the opening degree by the ratio of the open area to the total area when the valve is fully open.

[0051] (ii) Determine the degree of torsion of the manual gas valve and the control amount of the proportional solenoid valve.

[0052] It should be noted that by means of sensors (such as potentiometers, Hall elements, etc.), the degree of torsion of the manual gas valve can be detected in real time. This degree of torsion can intuitively reflect the opening condition of the manual valve and is presented in the form of an angle or a displacement amount, etc. For the proportional solenoid valve, its control amount is closely related to the magnitude of the current passed. Different current values correspond to different valve openings. By detecting the magnitude of the current, the control amount of the proportional solenoid valve can be determined, and then its opening state can be clarified.

[0053] (iii) Calculate the first opening degree relative to the shape information based on the degree of torsion and the control amount.

[0054] According to the shape information of the gas valve, convert the degree of torsion of the manual gas valve and the control amount of the proportional solenoid valve to obtain the first opening degree relative to this shape. For example, if the valve is a sector-shaped valve core, when it is known that the manual valve is twisted by a certain angle, through the pre-established correspondence between the angle and the sector opening degree, as well as the opening degree change corresponding to the control amount of the proportional solenoid valve, the first opening degree at this time is comprehensively calculated.

[0055] (iiii) Calculate the first linear relationship between the opening degree of the gas valve and the gas flow rate based on the shape information.

[0056] Specifically, calculate the standard opening degree characterization value of the manual gas valve according to the shape information, calculate the area of the opening region of the gas valve according to the opening degree of the gas valve, take the ratio of the area of the opening region to the total valve area calculated from the shape information as the standard opening degree characterization value, form a calibration pair with the standard opening degree characterization value and the corresponding gas flow rate, calibrate the calibration parameters in the first linear relationship, and obtain the first linear relationship. Considering that the ways to measure the opening degree of valves with different shapes are different, in order to adapt to various shapes of valves, calculate the standard characterization value of the valve according to the area ratio, which effectively improves the accuracy of the calculation. The first opening degree refers to the scale at which the valve opens under the control of the manual knob in the manual gas valve and under the current control of the proportional solenoid valve. There is a preset corresponding relationship between how much the control knob in the manual gas valve rotates and how much the valve opens. When the hydrodynamic formula is determined and the pressure difference and gas density are constant, the flow rate is proportional to the flow-through area. At this time, the flow-through area has a linear correlation with the standard opening degree characterization value (α1). The first linear relationship is: Q1 = α1·A + B, where A and B are calibration parameters.

[0057] (iiiii) Calculate the real-time gas flow rate based on the first linear relationship and the first opening degree.

[0058] Combined with the above description, for example, when α1 = 50%, it is calculated that Q1 = 5 L / min.

[0059] It should be noted that gas combustion requires air. When the manual gas valve is opened wider, there must also be enough air at the same time. Otherwise, if there is too much gas and too little air, the combustion will be incomplete and carbon monoxide will be produced.

[0060] (2) Simulate the flow and mixing process of the gas flow and air at the gas outlet, and determine the mixed flow rate at the combustion outlet as the first gas flow rate.

[0061] It should be noted that in terms of nature, the flow rate of the outflowing mixed gas (the first gas flow rate) = gas flow rate + air flow rate. It should also be noted that during actual mixing, the gases will mix, and the flow rate of the mixed gas may be slightly smaller than the simple addition. Specifically, based on the oxygen content detection device to detect the oxygen content in the air at the gas outlet, determine the oxygen distribution information in the combustion space according to the detected oxygen content, and determine the mixed flow rate at the combustion outlet according to the gas mixing mechanism between the oxygen distribution information and the gas flow rate output at the gas outlet. For the sake of simplified calculation, the mixed flow rate can be regarded as the sum of the gas flow rate and the oxygen content in the air. For accurate calculation, the gas flow rate calculated by the mixing mechanism after mixing can be used as the first gas flow rate.

[0062] S103. Calculate the ideal combustion temperature based on the first gas flow rate.

[0063] It should be noted that the ideal combustion temperature refers to the temperature corresponding to the heat released when the gas and air are fully mixed and burned in the theoretical ratio, and the initial temperature of the gas, the mixing ratio, and the heat generated by combustion need to be considered comprehensively.

[0064] Specifically, calculating the ideal combustion temperature based on the first gas flow rate includes:

[0065] (1) Calculate the temperature weights corresponding to the air and gas respectively according to the proportion of the air flow rate and the gas flow rate in the first gas flow rate.

[0066] Based on the first gas flow rate, the air flow rate, and the gas flow rate obtained in the previous steps, the proportion of the air flow rate and the gas flow rate in the first gas flow rate (the ratio of the air flow rate to the first gas flow rate, the ratio of the gas flow rate to the first gas flow rate) can be obtained, and then based on this ratio, the temperature weights corresponding to the air and gas (consistent with the ratio) can be determined. Among them, the temperature weight reflects the proportion of the air and gas in the mixed gas and is used to calculate the weighted average of the initial temperature.

[0067] (2) Determine the initial temperature of the gas and the initial temperature of the air.

[0068] It should be noted that the initial temperature is the temperature before the gas enters the combustion chamber (such as the ambient temperature or the preheating temperature of the pipeline). Specifically, the initial temperature of the fuel gas and the initial temperature of the air can be directly obtained based on relevant equipment.

[0069] (3) Calculate the weighted sum of the initial temperatures of the fuel gas and the air based on the initial temperature and the corresponding temperature weights, and calculate the initial temperature of the first fuel gas flow rate.

[0070] The initial temperature of the first fuel gas flow rate is the weighted average of the temperatures of each gas component according to the proportion. For example, if the ratio of the air flow rate to the first fuel gas flow rate is 0.8, the ratio of the fuel gas flow rate to the first fuel gas flow rate is 0.2, and the obtained initial temperatures of the air and the fuel gas are 298K and 303K respectively, then the initial temperature T 初始 = 0.8×298 + 0.2×303.

[0071] (4) Calculate the ideal combustion temperature based on the sum value of the initial temperature and the heat generated by combustion, where the heat generated by combustion is calculated as the ratio of the product of the enthalpy change of fuel gas combustion and the molar flow rate corresponding to the first fuel gas flow rate and the average constant-pressure specific heat capacity of the mixed gas.

[0072] Specifically, the theoretical combustion temperature can be calculated according to the thermodynamic formula , and the formula is as follows:

[0073] ;

[0074] Among them, (enthalpy change of methane combustion), is the average constant-pressure specific heat capacity of the mixed gas, is the molar flow rate corresponding to the first fuel gas flow rate, T 初始 is the initial temperature of the first fuel gas flow rate.

[0075] It should also be noted that the values of the molar flow rate and the average constant-pressure specific heat capacity will vary with the mixing ratio and mixing degree of the fuel gas and oxygen.

[0076] S104. Output the mixed gas corresponding to the first fuel gas flow rate, and burn to generate an initial flame.

[0077] It should be noted that the mixed gas is output from the combustion outlet, directly enters the combustion area, and then is ignited by the ignition device to burn and form an initial flame. Among them, the initial flame includes an inner flame and an outer flame. The inner flame is close to the combustion outlet, where there is insufficient oxygen and incomplete combustion. The main components are unburned fuel gas and decomposition products (such as H2, CO), and the temperature is relatively low. The outer flame is on the outside of the inner flame, where there is sufficient oxygen and complete combustion, generating CO2 and H2O, and the temperature is the highest, which is the main heat generation area.

[0078] S105. Detect the inner flame temperature and outer flame temperature of the initial flame. Starting from the detection position corresponding to the inner flame temperature and ending at the detection position corresponding to the outer flame temperature, predict the temperature change path between the starting point and the ending point with a preset step size, and determine the inner and outer flame boundaries of the initial flame based on the temperature change path.

[0079] It should be noted that detecting the inner flame temperature and outer flame temperature of the initial flame includes:

[0080] (1) Determine the minimum flame size based on the external shape structure of the gas stove.

[0081] Gas stoves with different external shape structures can maintain different minimum flame sizes stably. This is because factors such as the burner design of the gas stove, the size and distribution of the fire holes, and the diameter of the gas supply pipeline will all affect the stability of the flame. For example, a gas stove with smaller and denser fire holes may have a relatively smaller and more stable minimum flame; while a gas stove with larger and sparser fire holes may require a larger minimum flame to maintain stable combustion. Suppose a certain gas stove, through experimental testing and design requirements, the flame height corresponding to its minimum flame size is 2 cm.

[0082] (2) Determine the empirical size intervals of the inner flame and the outer flame based on the minimum flame size and the flame combustion mechanism.

[0083] The flame combustion mechanism shows that the inner flame is the area where the gas is not fully burned and the temperature is relatively low; the outer flame is the area where the gas is fully burned and the temperature is relatively high. According to a large number of experiments and experience summaries, after determining the minimum flame size, the proportion ranges of the inner flame and the outer flame in the entire flame height can be roughly determined, so as to obtain their empirical size intervals. For example, for the above-mentioned gas stove with a minimum flame height of 2 cm, according to experience, the inner flame height usually accounts for 20%-40% of the total flame height, and the outer flame height accounts for 60%-80%. Then the empirical size interval of the inner flame is 0.4-0.8 cm, and the empirical size interval of the outer flame is 1.2-1.6 cm.

[0084] (3) Calculate the inner flame height interval and the outer flame height interval based on the empirical size intervals.

[0085] Using the previously obtained empirical size intervals of the inner flame and the outer flame, combined with the geometric shape and combustion characteristics of the flame, calculate the inner flame height interval and the outer flame height interval. Generally speaking, the flame height is related to factors such as the gas flow rate and the air supply volume. Through the known minimum flame size and the previously obtained empirical ratio, the height intervals of the inner flame and the outer flame in the minimum flame state can be calculated. For example, the height corresponding to the previously calculated empirical size interval of the inner flame is 0.4-0.8 cm, and the outer flame is 1.2-1.6 cm.

[0086] (4) Determine the inner flame detection height and the outer flame detection height from the inner flame height range and the outer flame height range.

[0087] For example, the lowest value, median value, etc. in the range can be selected as the set height of the sensor. Selecting different values may affect the accuracy of temperature detection and need to be weighed according to the actual situation.

[0088] (5) Set a first temperature sensor at the inner flame detection height and a second temperature sensor at the outer flame detection height.

[0089] Accurately install the temperature sensor at the determined detection height position so as to accurately measure the temperatures of the inner flame and the outer flame. For example, install the first temperature sensor at a position 0.4 cm away from the combustion outlet to detect the inner flame temperature, and install the second temperature sensor at a position 1.4 cm away from the combustion outlet to detect the outer flame temperature.

[0090] (6) The first temperature sensor detects the inner flame temperature, and the second temperature sensor detects the outer flame height.

[0091] The temperature sensors start to work and measure the temperatures of the inner flame and the outer flame in real time. Assume that the first temperature sensor measures the inner flame temperature as 800 °C and the second temperature sensor measures the outer flame temperature as 1200 °C.

[0092] It should also be noted that taking the detection position corresponding to the inner flame temperature as the starting point and the detection position corresponding to the outer flame temperature as the end point, predicting the temperature change path between the starting point and the end point with a preset step size includes:

[0093] (1) Calculate the preset step size according to the height difference between the inner flame temperature detection sensor and the outer flame temperature detection sensor.

[0094] It should be noted that the preset step size determines the sampling interval when predicting the temperature change path. The smaller the step size, the more accurate the prediction result, but the calculation amount will also increase accordingly. For example, assume that the inner flame detection height is 0.4 cm, the outer flame detection height is 1.4 cm, and the height difference is 1 cm. If we preset to divide this height difference into 5 intervals for temperature prediction, then the preset step size is 1÷5 = 0.2 cm

[0095] (2) Taking the height where the starting point is located as the initial value and the preset step size as the increment, select each temperature calculation point.

[0096] Combined with the previous description, taking 0.4 cm of the inner flame detection height as the initial value and 0.2 cm as the step size, sequentially select the temperature calculation points. Then the heights of these calculation points are 0.4 cm, 0.6 cm, 0.8 cm, 1.0 cm, 1.2 cm, and 1.4 cm.

[0097] (3) For each temperature calculation point, the real-time molar flow rate of the mixed gas is calculated based on the distance between the current temperature calculation point and the combustion outlet.

[0098] It's important to note that as the gas mixture propagates, its molar flow rate decreases. In other words, the greater the distance, the less gas mixture can burn. This is because some gas has already participated in the combustion reaction during propagation. Furthermore, the real-time molar flow rate of the gas mixture is calculated based on the relationship between propagation loss and propagation distance.

[0099] For example, through experimental and theoretical analysis, the relationship between the propagation loss and propagation distance of the mixed gas is obtained as follows: , where n is the molar flow rate of the mixed gas at a distance d from the combustion outlet, is the molar flow rate of the mixed gas at the combustion outlet, k is the attenuation coefficient (obtained by experimental calibration), and the real-time molar flow rate of the mixed gas can be calculated based on this relationship.

[0100] (4) Calculate the real-time constant-pressure specific heat capacity of the mixed gas flowing to the current temperature calculation point based on the propagation mechanism of air and gas after the mixed gas is output from the combustion outlet.

[0101] As air and gas propagate, the gas and oxygen in the combustion environment come into more complete contact, improving the mixing of the mixed gases and, consequently, combustion. This further alters the constant-pressure specific heat capacity, which is associated with the mixing degree. Therefore, based on the propagation mechanism of the two, the mixing degree of the mixed gases is first calculated. The real-time constant-pressure specific heat capacity is then calculated based on the amount of mixed gas at the current temperature calculation point and the mixing degree. The specific calculation process is described in the related art and will not be further elaborated here.

[0102] (5) Calculate the real-time product of the molar flow rate of the mixed gas corresponding to the current temperature calculation point and the real-time constant-pressure specific heat capacity.

[0103] Specifically, the real-time molar flow rate of the mixed gas corresponding to the current temperature calculation point is multiplied by the real-time constant-pressure specific heat capacity to obtain the real-time product. For example, if the real-time molar flow rate of the mixed gas is 0.0997 mol / s and the real-time constant-pressure specific heat capacity is 29.5 J / (mol·K), then their product is 0.0997×29.5≈2.94 J / (s·K).

[0104] (6) Calculating the combustion change at the current temperature calculation point based on the ratio of the gas combustion enthalpy change to the real-time product.

[0105] Assume that the combustion enthalpy of the gas is (Methane combustion enthalpy change), according to the formula: ;

[0106] Among them, is the combustion change amount, n is the molar flow rate of the real-time mixed gas, is the real-time specific heat capacity at constant pressure (i.e., the average specific heat capacity at constant pressure of the mixed gas). Then, we can obtain: (This is only the theoretical calculated value. In practice, heat dissipation and other factors need to be considered for correction).

[0107] (7) Take the sum of the combustion change amount at the current temperature calculation point and the real-time temperature value calculated at the previous temperature calculation point as the real-time temperature value at the current temperature calculation point.

[0108] It should be noted that assume the real-time temperature value at the previous calculation point (at 0.4 cm) is 800 °C, and the combustion change amount at the current calculation point (at 0.6 cm) after correction is 100 °C. Then the real-time temperature value at the current calculation point is 800 + 100 = 900 °C. Through such iterative calculations, the real-time temperature values at each calculation point from the inner flame to the outer flame can be obtained, thereby obtaining the temperature change path.

[0109] It should also be noted that determining the inner and outer flame boundaries of the initial flame based on the temperature change path includes:

[0110] (1) Determine the demarcation value of the ideal mixing ratio of fuel gas and oxygen for the inner and outer flames according to the flame combustion mechanism.

[0111] According to the chemical principle of flame combustion, there is relatively more fuel gas and insufficient oxygen in the inner flame, and the combustion is incomplete; the mixing ratio of fuel gas and oxygen in the outer flame is closer to the ideal state, and the combustion is more complete. Through theoretical analysis and experimental research, a demarcation value of the ideal mixing ratio of fuel gas and oxygen can be determined. For example, for the combustion of natural gas (the main component is methane), when the volume ratio of fuel gas to oxygen reaches 1:2, the combustion is the most complete, and this ratio can be used as the demarcation value of the ideal mixing ratio for the inner and outer flames.

[0112] (2) Calculate the ideal mixed gas state corresponding to the demarcation value based on the ideal mixing ratio.

[0113] According to the ideal gas state equation and stoichiometric relationship, combined with the ideal mixing ratio determined above, the state parameters such as the pressure, temperature, and volume of the ideal mixed gas corresponding to the demarcation value can be calculated. For example, under standard atmospheric pressure, according to the ideal mixing ratio of fuel gas and oxygen and the chemical reaction formula, the temperature, density, and other parameters of the mixed gas in the ideal combustion state can be calculated.

[0114] (3) Calculate the ideal temperature demarcation value corresponding to the demarcation value based on the ideal mixed gas state.

[0115] Using the ideal mixture gas state parameters calculated previously, combined with thermodynamic knowledge and the heat effect of the combustion reaction, calculate the ideal temperature boundary value corresponding to the ideal mixing ratio boundary value. Assume that after calculation, the ideal temperature boundary value is obtained as 1500 °C.

[0116] (4)Determine the boundary between the inner flame and the outer flame based on the ideal temperature boundary value and the temperature change path.

[0117] Compare the ideal temperature boundary value with the previously predicted temperature change path. Find the point in the temperature change path that is closest to the ideal temperature boundary value, and the height position corresponding to this point is the boundary between the inner flame and the outer flame. For example, in the temperature change path, when the height is 0.8 cm, the temperature is close to 1500 °C, then the height position of 0.8 cm is the boundary between the inner flame and the outer flame.

[0118] (5)Determine the propagation path of the mixed gas from the detection point of the outer flame temperature to the outside.

[0119] Through the principles of fluid mechanics and experimental observations, analyze the direction and manner of the mixed gas propagating outward from the outer flame detection point, and determine its propagation path. For example, the mixed gas may propagate outward in a diffusive manner, and its propagation path can be described by a diffusion model.

[0120] (6)Predict the outer boundary of the outer flame based on the propagation path, use the combustion outlet as the inner boundary of the inner flame, use the boundary as the outer boundary of the inner flame and the inner boundary of the outer flame, and use the outer boundary as the outer boundary of the outer flame to obtain the inner and outer flame boundaries.

[0121] According to the propagation path of the mixed gas and the relevant physical model, predict the outermost position that the outer flame can reach, so as to determine the outer boundary of the outer flame. For example, by simulating the diffusion process of the mixed gas, it is found that when the distance from the combustion outlet is 1.8 cm, the concentration of the mixed gas is already lower than the lower limit that can maintain combustion, then the position of 1.8 cm is the outer boundary of the outer flame.

[0122] Based on the previous calculations and analyses, clarify the specific boundary ranges of the inner flame and the outer flame. For example, the inner boundary of the inner flame is the combustion outlet (0 cm), and the outer boundary is 0.8 cm; the inner boundary of the outer flame is 0.8 cm, and the outer boundary is 1.8 cm. In this way, the inner and outer flame boundaries of the initial flame are completely determined.

[0123] S106. Determine the proportion of the inner and outer flames in the initial flame based on the inner and outer flame boundaries.

[0124] It should be noted that determining the proportion of the inner and outer flames in the initial flame based on the boundary between the inner and outer flames includes: determining the flame shape according to the outer boundary of the outer flame, determining the inner flame shape according to the outer boundary of the inner flame, calculating the proportion of the inner flame shape in the flame shape as the proportion of the inner flame; calculating the proportion of the outer flame shape in the flame shape as the proportion of the outer flame.

[0125] It should be noted that the outer boundary of the outer flame outlines the general contour of the entire flame. By determining the positions of the points on the outer boundary of the outer flame, the shape of the flame can be depicted. In actual situations, the flame shape may be relatively complex, and common ones are approximately conical, ellipsoidal, etc. For example, on a two-dimensional plane, we determined the coordinates of multiple points on the outer boundary of the outer flame through the previous steps, and connecting these points found that the flame shape is approximately a cone.

[0126] The outer boundary of the inner flame defines the range of the inner flame. Similarly, by determining the positions of the points on the outer boundary of the inner flame, the shape of the inner flame can be depicted. The inner flame shape is usually also related to the overall flame shape and may be a smaller similar shape inside the flame. Further, according to the determined inner flame shape and flame shape, calculate their volumes (for three-dimensional shapes) or areas (for two-dimensional shapes), and then divide the volume or area of the inner flame by the volume or area of the flame to obtain the proportion of the inner flame.

[0127] It should also be noted that the proportion of the outer flame can be calculated in two ways. One is to first determine the shape of the outer flame, then calculate its volume or area, and then divide it by the volume or area of the flame; the other method is to subtract the proportion of the inner flame from 1 to obtain the proportion of the outer flame.

[0128] Through the above steps, the proportions of the inner and outer flames in the entire flame can be accurately calculated based on the boundaries between the inner and outer flames of the initial flame. This proportion information can help further analyze the combustion state of the flame. For example, if the proportion of the inner flame is too large, it may indicate incomplete combustion, and parameters such as the mixing ratio of gas and air need to be adjusted; if the proportion of the outer flame is too large, it may be necessary to check whether there is excessive air, etc., so as to optimize and control the combustion process.

[0129] S107. Calculate the comprehensive real-time temperature of the initial flame based on the proportion, the inner flame temperature, and the outer flame temperature.

[0130] It should be noted that calculating the comprehensive real-time temperature of the initial flame based on the proportion, the inner flame temperature, and the outer flame temperature includes: calculating the weighted temperature of the inner flame by multiplying the inner flame temperature by the proportion of the inner flame, calculating the weighted temperature of the outer flame by multiplying the outer flame temperature by the proportion of the outer flame, and taking the sum of the weighted temperatures of the inner and outer flames as the comprehensive real-time temperature of the initial flame.

[0131] It should be noted that the weighted temperature of the inner flame is obtained by multiplying the inner flame temperature by the proportion of the inner flame. This is because the proportion of the inner flame reflects the relative size of the inner flame in the whole flame. Multiplying the inner flame temperature by its proportion can obtain the contribution degree of the inner flame to the comprehensive real-time temperature. For example, through the previous steps, the proportion of the inner flame is calculated to be 0.3 (i.e., 30%), and the inner flame temperature is 800 °C, then the weighted temperature of the inner flame is 800×0.3 = 240 °C.

[0132] Similarly, similar to the calculation of the weighted temperature of the inner flame, the weighted temperature of the outer flame is the product of the outer flame temperature and the proportion of the outer flame. The proportion of the outer flame represents the relative size of the outer flame in the whole flame. Multiplying it by the temperature can obtain the contribution of the outer flame to the comprehensive real-time temperature. If the proportion of the outer flame is 0.7 (i.e., 70%) and the outer flame temperature is 1200 °C, then the weighted temperature of the outer flame is 1200×0.7 = 840 °C.

[0133] Furthermore, adding the weighted temperatures of the inner flame and the outer flame gives the comprehensive real-time temperature of the initial flame. This temperature comprehensively considers the temperatures of the inner flame and the outer flame and their proportions in the flame, and can more accurately represent the overall temperature situation of the flame. According to the previous calculations, the weighted temperature of the inner flame is 240 °C, and the weighted temperature of the outer flame is 840 °C, then the comprehensive real-time temperature of the initial flame is 240 + 840 = 1080 °C.

[0134] S108. Calculate the second opening degree of the proportional electromagnetic valve based on the difference between the comprehensive real-time temperature and the ideal combustion temperature, and control the proportional electromagnetic valve according to the second opening degree to complete the gas output.

[0135] Combined with the previous content, assuming the comprehensive real-time temperature is 1080 °C and the ideal combustion temperature is 1100 °C, then the temperature difference is -20 °C.

[0136] The calculating the second opening degree of the proportional electromagnetic valve based on the difference between the comprehensive real-time temperature and the ideal combustion temperature includes: taking the difference as the independent variable, taking the second opening degree of the proportional electromagnetic valve as the dependent variable, constructing a feedback control algorithm calculation model; calibrating the calculation coefficient of the feedback control algorithm calculation model according to the parameter information of the gas valve; determining the temperature error cumulative calculation time according to the opening and closing time of the gas manual valve; taking the cumulative error within the temperature error cumulative calculation time as the integral term in the feedback control algorithm calculation model, and calculating the second opening degree of the proportional electromagnetic valve according to the difference.

[0137] Specifically, the second opening value under the calculated difference can be obtained according to the PID control method. PID control consists of three parts: proportional (P), integral (I), and derivative (D). Its basic principle is to adjust the control quantity (i.e., the opening of the proportional solenoid valve) according to the error of the system (i.e., the temperature difference ΔT) so that the system output is as close as possible to the ideal value.

[0138] Among them, the role of the proportional part is to adjust the control quantity proportionally according to the magnitude of the error. The proportional coefficient determines the strength of the proportional action. The calculation formula is . For example, assuming = 0.5, then the output P of the proportional part = 0.5 × (-20) = -10. The integral part is used to eliminate the steady-state error of the system. It integrates the error. As time accumulates, the integral term will gradually increase, so that the control quantity is continuously adjusted until the error is zero. The integral coefficient , determines the strength of the integral action. The output calculation formula of the integral part is . Assuming = 0.1, and within a period of time t, the error ΔT remains unchanged (for simplicity of calculation), then the output I of the integral part = 0.1 × (-20) × t = -2t. The derivative part adjusts the control quantity according to the rate of change of the error. It can predict the change trend of the error and make adjustments in advance, thus improving the dynamic performance of the system. The derivative coefficient determines the strength of the derivative action. The output calculation formula of the derivative part is . Assuming = 0.05, if the rate of change of the error ΔT per unit time is -5℃ / s (i.e., the temperature is decreasing), then the output D of the derivative part = 0.05 × (-5) = -0.25.

[0139] It should be noted that the total output U of the PID control is the sum of the outputs of the proportional, integral, and derivative parts, that is, U = P + I + D. Substituting the calculated values of P, I, and D into the formula, we can get U = -10 - 2t - 0.25.

[0140] Furthermore, the second opening α2 of the proportional solenoid valve is calculated according to the total output U of the PID control. For example, assuming there is a mapping relationship such that α2 = U + α1 (where α1 is the initial opening, assumed to be 0 here), then, α2 = -10 - 2t - 0.25. However, in actual applications, the opening value needs to be limited within a certain range, such as between 0 and 100%. If the calculated α2 exceeds this range, corresponding processing is required, such as limiting it to 0 or 100%.

[0141] It should be noted that according to the difference between the comprehensive real-time temperature and the ideal combustion temperature, the second opening degree of the proportional electromagnetic valve can be calculated. This opening degree value will be used to adjust the gas flow rate, so as to make the combustion process closer to the ideal state, improve the combustion efficiency, reduce energy waste and pollutant emissions. At the same time, the parameters of the PID control method can be adjusted and optimized according to the actual situation to obtain better control effects. For example, if the system responds slowly to errors, the proportional coefficient value can be appropriately increased; if there is a large steady-state error in the system, the integral coefficient value can be increased; if the dynamic performance of the system is poor, the derivative coefficient value can be adjusted to improve it. In practical applications, it is also necessary to consider requirements such as the complexity of the system, interference factors, and control accuracy to further optimize and improve the PID control method.

[0142] It should also be noted that after controlling the proportional electromagnetic valve according to the second opening degree and completing the gas output, it further includes:

[0143] (1) Detect the CO concentration in the combustion space in real time.

[0144] It should be noted that after the proportional electromagnetic valve is opened according to the second opening degree, the amount of gas will increase and the size of the flame will further increase. However, when the oxygen content in the air remains unchanged, the concentration of CO in the air will increase significantly. At this time, in order to ensure that the flame temperature increases while the flame size increases, that is, the combustion is sufficient, blindly increasing the gas volume will cause incomplete combustion of the gas, wasting gas and easily causing too high a CO concentration in the air. At this time, for safety reasons, the opening degree of the proportional electromagnetic valve should be appropriately adjusted so that while meeting the requirement of increasing the opening degree, the gas and oxygen can still be fully mixed and the gas can be fully utilized for combustion.

[0145] (2) Calculate the gas adjustment amount under the ideal mixing ratio based on the first opening degree, the second opening degree, and the CO concentration.

[0146] Specifically, the total amount of gas entering the burner is calculated based on the first and second openings. A CO concentration is predicted based on the quantitative relationship between the initial oxygen content and the total amount of gas, according to the initial oxygen content in the air detected by the oxygen content detection device. A correction coefficient is determined based on the ratio of the predicted CO concentration to the measured CO concentration. A correction value for the total amount of gas is calculated based on the correction coefficient. An ideal mixing ratio for ideal combustion is determined based on the correction value of the total amount of gas and the combustion mechanism. A maximum amount of gas is calculated based on the mixing ratio and the initial oxygen content in the air. A gas adjustment amount is calculated based on the difference between the total amount of gas and the maximum amount of gas. In actual mixing, the mixing of gas and oxygen may not reach the ideal mixing ratio depending on the mixing environment. Therefore, considering the difference between the actual mixing and the ideal mixing as a correction coefficient, the gas level that can achieve the ideal mixing is calculated. Specifically, the error mixture of the total amount of gas is calculated to be equivalent to the ideal mixing level. Based on this, the oxygen state in the air can be accurately calculated to be able to ideally blend with the gas level, thereby obtaining the maximum amount of gas that can achieve the maximum mixing.

[0147] (3) Adjusting the second opening based on the shape of the proportional electromagnetic valve and the gas adjustment amount.

[0148] After gas output is complete, further optimization of the combustion process is required to achieve more precise combustion control. At this point, it is essential to measure the actual oxygen content in the air within the combustion space. High-precision oxygen content sensors can be used to accurately and in real time obtain oxygen content data within the combustion space.

[0149] When the current combustion environment is relatively oxygen-deficient, the gas cannot burn fully, potentially leading to reduced combustion efficiency and the generation of pollutants. To improve this situation, the second opening of the proportional solenoid valve needs to be adjusted based on the difference between the maximum gas volume that can ideally mix with oxygen in the current air and the current actual gas volume.

[0150] Specifically, after the second opening degree has been self-regulated for a period of time, the method further includes statistically analyzing the opening degree of the proportional solenoid valve before adjustment and the opening degree after adjustment, as well as the calculated gas adjustment amount, and fitting a mathematical model with the gas adjustment amount as the independent variable and the opening degree adjustment value of the proportional solenoid valve as the dependent variable (this model is obtained based on a large amount of experimental data and theoretical analysis, reflecting the relationship between the gas adjustment amount and the opening degree adjustment of the proportional solenoid valve, and does not require repeated conversion according to shape information), and calculating the opening degree value that the proportional solenoid valve needs to decrease to achieve a more ideal combustion state. For example, if the gas adjustment amount is negative, it means that the oxygen required for combustion is seriously insufficient. At this time, according to the model calculation, it may be necessary to decrease the opening degree of the proportional solenoid valve by a certain proportion to reduce the gas flow rate, so that the gas and the oxygen in the air can be better matched and promote the full progress of the combustion reaction. On the contrary, when the gas adjustment amount is positive, it indicates that the oxygen in the current combustion environment is relatively sufficient, and the opening degree of the proportional solenoid valve can be appropriately increased to avoid the increase of incomplete combustion products. Similarly, based on the above mathematical model, the opening degree value that should be increased is calculated, so as to achieve precise adjustment of the second opening degree of the proportional solenoid valve.

[0151] In specific implementation, considering the stability and safety of the gas combustion system, the adjustment of the opening degree is carried out in a step-by-step fine-tuning manner. After each adjustment, relevant parameters (such as CO concentration, flame temperature, etc.) in the combustion space need to be re-detected to evaluate the adjustment effect, and adjustments are made again according to the new data until the combustion state reaches the best. The method provided by the present invention can optimize the gas combustion process to the greatest extent, improve the combustion efficiency, reduce pollutant emissions, and ensure that the combustion process is always in a safe, stable and efficient state when the air volume is fixed.

[0152] Specifically, the content of CO after combustion is detected in real time, that is, the concentration in the air concentration is detected, and a threshold value is set. When it exceeds the standard, the gas flow rate is gradually and repeatedly reduced according to the following formula until:

[0153] .

[0154] In terms of combustion efficiency, the double-valve structure and multi-parameter calculation in the method provided in this embodiment enable precise control of the gas-air mixing ratio. In terms of safety performance, the independent mechanical structure of the gas manual valve ensures gas supply during power failure, and the status monitoring of the gas manual valve avoids gas leakage caused by misoperation.

[0155] Embodiment 2:

[0156] Figure 2 is a schematic structural diagram of the gas manual valve of the gas valve provided by this application. Figure 3Schematic diagram of the proportional solenoid valve structure of the gas valve provided by this application. Please also refer to Figure 2 and Figure 3 , the gas valve at least includes a valve body, a gas manual valve, and a proportional solenoid valve; the gas manual valve and the proportional solenoid valve are connected to the same valve port and jointly control the flux of the same valve port.

[0157] The gas manual valve is located below the valve body 1. The lower block 5 is fixedly connected to the valve body through the second thread 7, and the second thread plays a fixing role. An adjusting nut 4, an adjusting pillar 2, and a seal 3 are sequentially arranged on the lower block 5. Among them, the seal 3 is fixed on the adjusting pillar 2, the adjusting pillar 2 is connected to the adjusting nut 4 through a pin, and the adjusting pillar 2 is movably connected to the lower block 5 through the first thread 6, and the first thread plays an adjusting role;

[0158] The proportional solenoid valve is located above the valve body 1. The magnetic isolation tube 12 is fixedly connected to the valve body and nested in the coil assembly 9. The moving iron core 8, the adjusting spring 11, and the adjusting screw 10 are stacked in the magnetic isolation tube 12 from top to bottom in sequence; among them, a seal 3 is fixed on the moving iron core 8, and the seal 3 is in contact with the gas flow port above the valve body.

[0159] It should be noted that the adjusting nut 4 of the gas manual valve is threadedly connected to the adjusting pillar 2. By rotating the adjusting nut 4, the opening degree of the seal 3 and the gas flow port of the valve body can be controlled.

[0160] It also needs to be noted that the adjusting screw 10 of the proportional solenoid valve can be rotated to adjust the compression amount and elastic force of the adjusting spring 11, and then adjust the initial position of the moving iron core 8. The seal 3 fixed to the moving iron core 8 is in contact with the gas flow port above the valve body. When the moving iron core 8 moves up and down under the combined action of electromagnetic force and spring force, the seal 3 will move accordingly, thereby changing the relative position of the seal 3 and the gas flow port above the valve body, and realizing the adjustment of the opening degree of the gas flow port of the valve body. In addition, the proportional solenoid valve also includes a feedback adjustment device and a gas component detection device. The feedback adjustment device is used to adjust the gas flow according to the temperature at the rear end, and the gas component detection device is used to detect the gas components in the air.

[0161] The above are only the preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included within the scope of protection of this application.

Claims

1. A combustion flame adjustment method based on gas valve matching control, characterized in that, The method includes: Determine the first opening degree of the gas valve, where the gas valve is jointly controlled by a gas manual valve and a proportional solenoid valve; Determine the first gas flow rate at the combustion outlet based on the first opening degree; Calculate the ideal combustion temperature based on the first gas flow rate; Output the mixed gas corresponding to the first gas flow rate, and burn to generate an initial flame; Detect the inner flame temperature and outer flame temperature of the initial flame. Taking the detection position corresponding to the inner flame temperature as the starting point and the detection position corresponding to the outer flame temperature as the end point, predict the temperature change path between the starting point and the end point with a preset step size, and determine the inner and outer flame boundaries of the initial flame based on the temperature change path; Determine the proportion of the inner and outer flames in the initial flame based on the inner and outer flame boundaries; Calculate the comprehensive real-time temperature of the initial flame based on the proportion, the inner flame temperature, and the outer flame temperature; Calculate the second opening degree of the proportional solenoid valve based on the difference between the comprehensive real-time temperature and the ideal combustion temperature, and control the proportional solenoid valve according to the second opening degree to complete the gas output.

2. The method according to claim 1, wherein After controlling the proportional solenoid valve according to the second opening degree to complete the gas output, the method further includes: Real-time detect the CO concentration in the combustion space; Calculate the gas adjustment amount under the ideal mixing ratio based on the first opening degree, the second opening degree, and the CO concentration; Adjust the second opening degree based on the shape of the proportional solenoid valve and the gas adjustment amount.

3. The method according to claim 1, wherein The calculating the second opening degree of the proportional solenoid valve based on the difference between the comprehensive real-time temperature and the ideal combustion temperature includes: Taking the difference as the independent variable and the second opening degree of the proportional solenoid valve as the dependent variable, construct a feedback control algorithm calculation model; Calibrate the calculation coefficients of the feedback control algorithm calculation model according to the parameter information of the gas valve; Determine the temperature error cumulative calculation time according to the switching time of the gas manual valve; In the feedback control algorithm calculation model, take the cumulative error within the temperature error cumulative calculation time as the integral term, and calculate the second opening degree of the proportional solenoid valve according to the difference.

4. The method according to claim 1, characterized in that The determining the first gas flow rate at the combustion outlet based on the first opening degree includes: Calculate the gas flow rate based on the first opening degree, where the first opening degree is the sum of the opening degree of the gas manual valve and the opening degree of the proportional solenoid valve; Simulate the flow and mixing process of the gas flow rate and air at the gas outlet, and determine the mixed flow rate at the combustion outlet as the first gas flow rate.

5. The method according to claim 4, characterized in that The calculating the gas flow rate entering based on the first opening degree includes: Determine the shape information of the gas valve; Determine the torsion degree of the gas manual valve and the control amount of the proportional solenoid valve; Calculate the first opening degree relative to the shape information based on the torsion degree and the control amount; Calculate the first linear relationship between the opening degree of the gas valve and the gas flow rate based on the shape information; Calculate the real-time gas flow rate based on the first linear relationship and the first opening degree.

6. The method according to claim 1, wherein The calculating the ideal combustion temperature based on the first gas flow rate includes: Calculate the temperature weights corresponding to air and gas respectively according to the proportion of air flow and gas flow in the first gas flow; Determine the initial temperature of the gas and the initial temperature of the air; Calculate the weighted sum of the initial temperatures of the gas and the air with the initial temperature and the corresponding temperature weights, and calculate the initial temperature of the first gas flow; Calculate the ideal combustion temperature based on the sum value of the initial temperature and the heat generated by combustion, where the heat generated by combustion is calculated by the ratio of the product of the enthalpy change of gas combustion and the molar flow rate corresponding to the first gas flow and the average constant pressure specific heat capacity of the mixed gas.

7. The method according to claim 1, wherein The detecting the inner flame temperature and the outer flame temperature of the initial flame includes: Determine the minimum flame size based on the external shape structure of the gas stove; Determine the empirical size ranges of the inner flame and the outer flame based on the minimum flame size and the flame combustion mechanism; Calculate the inner flame height range and the outer flame height range with the empirical size ranges; Determine the inner flame detection height and the outer flame detection height from the inner flame height range and the outer flame height range; Set a first temperature sensor at the inner flame detection height and a second temperature sensor at the outer flame detection height; The first temperature sensor detects the inner flame temperature, and the second temperature sensor detects the outer flame height.

8. The method according to claim 1, wherein The predicting the temperature change path between the starting point and the ending point with the preset step length with the detection position corresponding to the inner flame temperature as the starting point and the detection position corresponding to the outer flame temperature as the ending point includes: Calculate the preset step length according to the height difference between the inner flame temperature detection sensor and the outer flame temperature detection sensor; Take the height where the starting point is located as the initial value, and take the preset step length as the increment to select each temperature calculation point; For each temperature calculation point, calculate the real-time molar flow rate of the mixed gas according to the distance of the current temperature calculation point from the combustion outlet; Calculate the real-time constant pressure specific heat capacity of the mixed gas flowing to the current temperature calculation point with the propagation mechanism of air and gas after the mixed gas exits the combustion outlet; Calculate the real-time product of the real-time molar flow rate of the mixed gas corresponding to the current temperature calculation point and the real-time constant pressure specific heat capacity; Calculate the combustion change amount at the current temperature calculation point based on the ratio of the enthalpy change of gas combustion and the real-time product; Take the sum value of the combustion change amount at the current temperature calculation point and the real-time temperature value calculated at the previous temperature calculation point as the real-time temperature value of the current temperature calculation point.

9. The method according to claim 1, characterized in that, The determining the inner and outer flame boundaries of the initial flame based on the temperature change path includes: Determine the demarcation value of the ideal mixing ratio of gas and oxygen for the inner and outer flames of the flame according to the flame combustion mechanism; Calculate the ideal mixed gas state corresponding to the demarcation value based on the ideal mixing ratio; Calculate the ideal temperature demarcation value corresponding to the demarcation value based on the ideal mixed gas state; Determine the demarcation boundary between the inner flame and the outer flame based on the ideal temperature demarcation value and the temperature change path; Determine the propagation path of the mixed gas from the detection point of the outer flame temperature to the outside; Predict the outer boundary of the outer flame according to the propagation path, take the combustion outlet as the inner boundary of the inner flame, take the demarcation boundary as the outer boundary of the inner flame and the inner boundary of the outer flame, and take the outer boundary as the outer boundary of the outer flame to obtain the inner and outer flame boundaries.

10. A gas valve, characterized in that, The gas valve is applied to the method described in any one of claims 1-9. The gas valve at least includes a valve body, a gas manual valve, and a proportional solenoid valve; the gas manual valve and the proportional solenoid valve are connected to the same valve port and jointly control the flux of the same valve port. The gas manual valve is located below the valve body. The lower block is fixedly connected to the valve body by threads. An adjusting nut, an adjusting strut, and a seal are sequentially arranged on the lower block. Among them, the seal is fixed on the adjusting strut, the adjusting strut is connected to the adjusting nut by a pin, and the adjusting strut is movably connected to the lower block by threads. The proportional solenoid valve is located above the valve body. The magnetic isolation tube is fixedly connected to the valve body and nested in the coil assembly. The moving iron core, the adjusting spring, and the adjusting screw are sequentially stacked in the magnetic isolation tube from top to bottom; among them, a seal is fixed on the moving iron core, and the seal contacts the gas flow port above the valve body.

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