Hydrogen-doped natural gas injection combustion test device and test method

Abstract

The invention discloses a hydrogen-doped natural gas injection combustion test device and method. The hydrogen-doped natural gas injection combustion test device comprises a mixing tank, and a mixing module is arranged in the mixing tank; the mixing module is respectively connected with a hydrogen storage tank and a natural gas storage tank; the outlet end of the mixing tank is connected with a temporary storage tank, the outlet end of the temporary storage tank is provided with a jet combustion module, the test device further comprises an observation module and a controller, and the observation module is used for collecting combustion characteristic parameters of jet flames; the controller is electrically connected with the hydrogen flow meter, the natural gas flow meter, the pressurization module and the observation module. Hydrogen-doped natural gas of any mixing proportion can be input according to needs, the diversity of the hydrogen-doped natural gas is improved, meanwhile, the temporary storage area and the mixing area are separated through the arrangement of the temporary storage tank, mixing operation can be synchronously carried out while spraying combustion is carried out, switching between different tank bodies is not needed any more, and the working efficiency is improved. And a large number of tank bodies are not required to be prepared for storing different hydrogen-doped natural gases, so that the convenience of equipment operation is improved.

Description

Technical Field

[0001] This application relates to the technical field of combustion detection equipment, and particularly relates to a hydrogen-doped natural gas injection combustion test device and a test method. Background Art

[0002] Hydrogen-doped natural gas refers to a mixture gas (HCNG) formed by mixing a certain proportion of hydrogen with natural gas, which is one of the important directions for hydrogen energy utilization. The proportion of hydrogen-doped natural gas is usually between 3% and 30%, and it can be transported through natural gas pipelines to end-users for direct use; Due to the differences in the physical and chemical properties of hydrogen and natural gas, the proportion of hydrogen doping needs to be strictly controlled. At the same time, in order to ensure the safe transportation of hydrogen-doped natural gas, it is necessary to study its combustion properties. In the prior art, combustion tests on hydrogen-doped natural gas with different proportions are generally carried out through a spraying test device. However, the above spraying combustion device needs to prepare multiple storage tanks in advance to store hydrogen-doped natural gas with different mixing proportions respectively. When multiple groups of experiments with different mixing proportions are required, it will not only cause the unlimited increase of storage tanks, but also require complex control procedures for the switching between different storage tanks, making the equipment inconvenient to use. Summary of the Invention

[0003] The main purpose of this application is to provide a hydrogen-doped natural gas injection combustion test device and a test method, aiming to solve the defect of inconvenient use in the prior art.

[0004] This application achieves the above object through the following technical solutions: A hydrogen-doped natural gas injection combustion test device, comprising: A mixing tank, in which a mixing module is arranged; the inlet ends of the mixing module are respectively connected to a hydrogen storage tank and a natural gas storage tank; a hydrogen flowmeter is further arranged between the mixing module and the hydrogen storage tank, and a natural gas flowmeter is arranged between the mixing module and the natural gas storage tank; A temporary storage tank, which is connected to the outlet end of the mixing tank through a pressurization module; A spraying combustion module, which is connected to the temporary storage tank; An observation module, which is used to collect infrared temperature images of the spraying flame; A controller, which is electrically connected to the hydrogen flowmeter, the natural gas flowmeter, the pressurization module and the observation module respectively.

[0005] Optionally, the mixing module includes a spray disc and a spray ring. The spray disc is coaxially arranged with the spray ring. A first intake pipe for connecting a hydrogen storage tank is arranged on the spray disc, and a second intake pipe for connecting a natural gas storage tank is arranged on the spray ring. A number of spray heads are arranged on the spray disc and the spray disc.

[0006] Optionally, an internal circulation pipe is further arranged on the temporary storage tank. The inlet end of the internal circulation pipe communicates with the bottom of the temporary storage tank, and its outlet end communicates with the top of the temporary storage tank. Along the gas flow direction, a circulation pump and a mixing module are sequentially arranged on the internal circulation pipe.

[0007] Optionally, the mixing module includes a mixing pipe. A spiral guide vane coaxial with the mixing pipe is arranged inside the mixing pipe. A number of mixing pins are arranged on the surface of the spiral guide vane, and the cross section of each mixing pin is arranged in a triangular structure.

[0008] Optionally, the injection combustion module includes an injection main pipe, a distribution plate and a number of combustion pipes. The outlet end of the injection main pipe communicates with the distribution plate. The inlet ends of the combustion pipes communicate with the distribution plate respectively, and nozzles of the same or different types are arranged at the outlet ends of the combustion pipes.

[0009] Correspondingly, the present application also discloses a test method based on the above test device, including the following steps: Set the mixing ratio, injection pressure and nozzle type of the hydrogen-enriched natural gas as required; Obtain an infrared image set of the injection flame; Set a number of temperature recognition thresholds, and extract a number of temperature distribution curve atlases from the infrared image set according to the temperature recognition thresholds; Obtain a number of injection flame morphology diagrams according to each temperature distribution curve atlas; Obtain injection flame morphology parameters according to the injection flame morphology diagrams.

[0010] Optionally, setting a number of temperature recognition thresholds and extracting a number of temperature distribution curve atlases from the infrared image set according to the temperature recognition thresholds includes the following steps: Set a number of temperature recognition thresholds according to the actual working conditions; Retrieve the infrared image set, perform gray processing on it, and obtain a gray image set of the injection flame; Perform gray value calibration according to each temperature recognition threshold to generate a gray-temperature conversion function; Calculate the recognition gray set according to the temperature recognition threshold and the gray-temperature conversion function; Extract the temperature distribution curve atlas from the gray image set according to the recognition gray set.

[0011] Optionally, perform gray value calibration according to each temperature recognition threshold to generate a gray-temperature conversion function, including the following steps: Obtain each temperature recognition threshold, and determine the fitting temperature range according to each of the temperature recognition thresholds; Randomly select a number of test temperatures within the fitting temperature range; Control the temperature of the adjustable blackbody furnace to any one of the test temperatures, and capture an infrared temperature image at this test temperature; Calculate the test gray value corresponding to this test temperature according to the infrared temperature image; Repeat the step of controlling the temperature of the adjustable blackbody furnace to any one of the test temperatures to obtain all test gray values; Fit and generate a gray-temperature conversion function according to each of the test temperatures and each of the test gray values.

[0012] Optionally, extract a temperature distribution curve atlas from the gray image set according to the recognition gray value set, including the following steps: Obtain any gray image from the gray image set; Divide the gray image into several standard cells, and mark the actual gray value of each standard cell; Extract any recognition gray value from the recognition gray value set; Extract all standard cells whose actual gray value is equal to the recognition gray value; Connect the extracted standard cells in series by a curve in a clockwise or counterclockwise direction to obtain a recognition temperature distribution curve, and collect it into the corresponding temperature distribution curve atlas; Repeat the step of extracting any recognition gray value from the recognition gray value set; Repeat the step of obtaining any gray image from the gray image set to obtain several temperature distribution curve atlases.

[0013] Optionally, obtain several jet flame morphology diagrams according to each of the temperature distribution curve atlases, including the following steps: Obtain any one of the temperature distribution curve atlases; Set reference points for each temperature distribution curve in the temperature distribution curve atlas respectively; Overlap each temperature distribution curve in the temperature distribution curve atlas according to the reference points to obtain a temperature distribution diagram; Construct a minimum bounding box for the temperature distribution diagram, and take the center line of the minimum bounding box as the jet flame morphology diagram; Repeat the step of obtaining any one of the temperature distribution curve atlases to obtain several jet flame morphology diagrams.

[0014] Compared with the prior art, the present application has the following beneficial effects: This application includes a mixing tank, and a mixing module is arranged inside the mixing tank; the inlet ends of the mixing module are respectively connected to a hydrogen storage tank and a natural gas storage tank; a hydrogen flowmeter is further arranged between the mixing module and the hydrogen storage tank, and a natural gas flowmeter is arranged between the mixing module and the natural gas storage tank; the outlet end of the mixing tank is connected to a temporary storage tank, and an injection combustion module is arranged at the outlet end of the temporary storage tank. The test device further includes an observation module and a controller, wherein the observation module is used to collect the combustion characteristic parameters of the injection flame; the controller is electrically connected to the hydrogen flowmeter, the natural gas flowmeter, the pressurization module and the observation module respectively; During use, first calculate the hydrogen and natural gas that need to be input according to the hydrogen blending ratio respectively, then input hydrogen and natural gas into the mixing tank, and realize the mixing of hydrogen and natural gas through the mixing module. At the same time, calculate the gas delivery volume through the hydrogen flowmeter and the natural gas flowmeter to facilitate the control of the blending ratio; the mixed gas is transported to the temporary storage tank for storage, and then is injected and burned through the injection combustion module. During the injection process, directly collect the infrared temperature image of the injection flame through the observation module, and analyze the relevant parameters of the injection flame based on the infrared temperature image; Compared with the prior art, this application can input hydrogen-enriched natural gas with any blending ratio according to needs. On the one hand, it improves the diversity of the test hydrogen-enriched natural gas and is conducive to improving the accuracy of the test; on the other hand, due to the existence of the temporary storage tank, the temporary storage area and the blending area can be separated from each other, that is, the blending operation can be carried out synchronously while the injection combustion is in progress, without the need to switch between different tanks, nor the need to prepare a large number of different tanks for storing hydrogen-enriched natural gas with different blending ratios, which improves the convenience of equipment operation and the response speed of the equipment is faster; at the same time, the structure of the equipment is also simplified, and the reliability and stability of the whole system are improved.

[0015] At the same time, this application produces hydrogen-enriched natural gas by on-site blending, which can effectively avoid the excess of hydrogen-enriched natural gas with a certain blending ratio and improve the gas utilization rate. Description of the Drawings

[0016] Figure 1 It is a schematic structural diagram of a hydrogen-enriched natural gas injection combustion test device provided by Embodiment 1 of this application; Figure 2 It is an exploded view of a hydrogen-enriched natural gas injection combustion test device provided by Embodiment 1 of this application; Figure 3 It is a schematic structural diagram of the mixing module; Figure 4 It is an exploded view of the mixing material module; Figure 5 For Figure 4 The enlarged view of part A in Figure 6 Explosion diagram of the jet combustion module; Figure 7 Flow chart of the test method provided in Embodiment 2 of the present application; Figure 8 Principle diagram for generating the jet flame morphology diagram; Reference numerals: 1 - mixing tank, 2 - hydrogen storage tank, 3 - natural gas storage tank, 4 - hydrogen flow meter, 5 - natural gas flow meter, 6 - temporary storage tank, 7 - jet combustion module, 8 - observation module, 9 - controller, 10 - injection plate, 11 - injection ring, 12 - first intake pipe, 13 - second intake pipe, 14 - injection head, 15 - internal circulation pipe, 16 - circulation pump, 17 - mixing pipe, 18 - spiral guide vane, 19 - mixing pin, 701 - injection main pipe, 702 - distribution plate, 703 - combustion pipe, 704 - nozzle.

[0017] The realization of the purpose, functional features and advantages of the present application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Embodiment

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0019] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0020] In the present invention, unless otherwise clearly defined and limited, terms such as "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral body; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0021] In addition, if the embodiments of the present invention involve descriptions such as "first" and "second", the descriptions of "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and / or" appearing throughout the text includes three parallel scenarios. Taking "A and / or B" as an example, it includes scenario A, or scenario B, or the scenario where both A and B are satisfied simultaneously. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions results in contradictions or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0022] Embodiment 1

[0023] Referring to Figures 1 to 6 , as an optional embodiment of the present application, this embodiment discloses a hydrogen-doped natural gas injection combustion test device, including a mixing tank 1, a hydrogen storage tank 2, and a natural gas storage tank 3. A mixing module is further provided in the mixing pipe. The mixing module includes a spray disc 10 and a spray ring 11. The spray disc 10 has a cylindrical structure, and the spray ring 11 has an annular structure. The spray disc 10 is disposed inside the spray ring 11 and is coaxially arranged with the spray ring 11. A first intake pipe 12 is further provided on the top surface of the spray disc 10, and a second intake pipe 13 is connected to the spray ring 11. The inlet end of the first intake pipe 12 is connected to the hydrogen storage tank 2, and the inlet end of the second intake pipe 13 is connected to the natural gas storage tank 3. Around the axis of the spray disc 10, a plurality of spray heads 14 are provided on the outer peripheral surface of the spray disc 10. At the same time, a plurality of spray heads 14 are also provided on the inner side surface of the spray ring 11. Each of the spray heads 14 on the spray disc 10 corresponds to each of the spray heads 14 on the spray ring 11 one by one, and along the radial direction of the spray disc 10, the two corresponding spray heads 14 are arranged facing each other. At the same time, a hydrogen storage tank 2 is provided on the first intake pipe 12, and a natural gas flowmeter 5 is provided on the second intake pipe 13. During use, the hydrogen flowmeter 4 and the natural gas flowmeter 5 are used to measure the delivery amounts of hydrogen and natural gas respectively, so as to achieve precise hydrogen blending. At the same time, since the injection nozzles 14 on the injection disk 10 are directly opposite to the injection nozzles 14 on the injection ring 11, the hydrogen and natural gas ejected in a high-pressure jet state will collide violently. While the collided air flow realizes its own uniform mixing, the dispersed air flow will also stir the gas in the mixing tank 1, thereby realizing the mixing of the gas in the tank into a mixed gas; Furthermore, the injection directions of the respective injection nozzles 14 can be adjusted to enhance the stirring and mixing effect on the gas in the mixing tank 1.

[0024] Furthermore, a gas pipeline is provided at the bottom of the mixing tank 1, and a pressurization module is provided on the gas pipeline. The outlet end of the pressurization module is communicated with the temporary storage tank 6; the pressurization module includes a pressurization pump; Furthermore, an internal circulation pipe 15 is provided on the temporary storage tank 6. The inlet end of the internal circulation pipe 15 is communicated with the bottom of the temporary storage tank 6, and its outlet end is communicated with the top of the temporary storage tank 6; along the gas flow direction, a circulation pump 16 and a mixing module are sequentially arranged on the internal circulation pipe 15. The mixing module includes a mixing pipe 17. Along the axis of the mixing pipe 17, both ends of the mixing pipe 17 are communicated with the internal circulation pipe 15 and the outlet end of the circulation pump 16 respectively; a spiral guide vane 18 coaxial with it is arranged in the mixing pipe 17, and a number of mixing pins 19 arranged in a staggered manner are arranged on the surface of the spiral guide vane 18; The cross-section of the mixing pin 19 is arranged in a triangular structure, and any edge thereof is facing the air flow direction; Furthermore, to improve the drainage effect, the two surfaces intersecting with the edge facing the air flow direction are arranged in an arc structure; During use, the circulation pump 16 is used to forcibly extract the air flow in the temporary storage tank 6 into the internal circulation pipe 15, and through the mixing pipe 17, the setting of the spiral guide vane 18 can not only guide the air flow direction, but also prolong the residence time of the air flow in the mixing pipe 17, which is beneficial to improving the mixing uniformity; Secondly, the mixing pins 19 with a triangular cross-section can cut the air flow, and the two split air flows will be diverted in two different directions. At the same time, since the respective mixing pins 19 are arranged in a staggered manner, air flow collisions will occur in the blank area between the two mixing pins 19, further improving the mixing uniformity; 7]]The setting of the internal circulation pipe 15 effectively strengthens the circulation of the hydrogen-enriched natural gas in the temporary storage tank 6, avoids the decrease in the uniformity of the hydrogen-enriched natural gas during storage, thereby ensuring the output of the hydrogen-enriched fuel gas at a relatively stable hydrogen blending concentration and ensuring the accuracy of the combustion test.

[0025] Further, the outlet end of the temporary storage tank 6 is also connected to an injection combustion module, which includes an injection main pipe 701, a flow distribution plate 702, and a number of combustion pipes 703. The inlet end of the injection main pipe 701 is communicated with the outlet end of the temporary storage tank 6, and its outlet end is communicated with the flow distribution plate 702. The inlet ends of the combustion pipes 703 are respectively communicated with the flow distribution plate 702, and the outlet ends of the combustion pipes 703 are provided with nozzles 704 that are the same or different; An electromagnetic valve for adjusting the on-off state is provided on each of the combustion pipes 703; During use, the staff selects the nozzle 704 according to needs to meet the test requirements. Compared with the prior art, when it is necessary to switch different nozzles 704, it can be achieved through the adjustment of the electromagnetic valve, and there is no need to manually replace the nozzle 704. It is not only more convenient to adjust, which is beneficial to improving the test efficiency, but also can effectively reduce the workload of the staff.

[0026] Further, combustion pipes 703 for burning excess hydrogen-doped natural gas are provided on both the temporary storage tank 6 and the mixing tank. At the same time, a purge pipe is provided on the top of the temporary storage tank 6, and the inlet end of the purge pipe is connected to an external purge nitrogen source; When the combustion test of hydrogen-doped natural gas with a certain mixing ratio ends, if the hydrogen-doped natural gas in the temporary storage tank 6 is not completely consumed, the excess hydrogen-doped natural gas is led out through the combustion pipe 703 and directly burned. Finally, nitrogen is introduced through the purge pipe to clean the residual hydrogen-doped natural gas in the temporary storage tank 6, so as to ensure that the hydrogen-doped natural gas is output with a more accurate mixing ratio; At the same time, corresponding sensors can be added at the outlet ends of the temporary storage tank 6 and the mixing tank to detect the mixing ratio of hydrogen; such as adding a palladium alloy nanofilmm hydrogen sensor.

[0027] It should be noted that equipment such as a pressure control device also needs to be set in the device of the present application. The above-mentioned equipment are all conventional equipment in the prior art and are widely used in technical fields such as natural gas transportation. Therefore, the above-mentioned equipment will not be described in the present application.

[0028] Further, the test device further includes an observation module 8 and a controller 9. The observation module 8 includes an infrared thermal imager; the controller 9 includes an industrial control computer and a PLC. The industrial control computer is connected to the PLC through a data bus, and the PLC is respectively electrically connected to equipment such as a hydrogen flowmeter 4, a natural gas flowmeter 5, a pressure pump, and an infrared thermal imager to realize data collection and automatic control.

[0029] Embodiment 2

[0030] Refer to Figure 7, as another alternative embodiment of the present application, it discloses a method for testing the injection combustion of hydrogen-doped natural gas, including the following steps: S1. Set the mixing ratio, injection pressure, and nozzle type of the hydrogen-doped natural gas as required; First, set the mixing ratio of the hydrogen-doped natural gas according to the specific arrangement of the hydrogen doping test. At the same time, set the injection pressure for the hydrogen-doped natural gas with each mixing ratio and the nozzle type of the burner respectively; At the same time, it is also necessary to set the total amount of the hydrogen-doped natural gas according to parameters such as the combustion duration; S2. Obtain an infrared image set of the injection flame; According to the set mixing ratio, hydrogen and natural gas are respectively transported to the mixing tank. The transportation amounts of hydrogen and natural gas are respectively measured by the hydrogen flowmeter and the natural gas flowmeter, so as to achieve precise hydrogen doping. At the same time, since the injection nozzles on the injection disc are directly opposite to the injection nozzles on the injection ring, the hydrogen and natural gas ejected in a high-pressure injection state will collide violently. While the collided air flow realizes its own uniform mixing, the scattered air flow will also stir the gas in the mixing tank, so as to realize the mixing of the gas in the tank as a mixed gas; After the mixing is completed, the hydrogen-doped natural gas is transported to the temporary storage tank through the pressurizing device and then input into the injection combustion module when the experiment is needed; During combustion, the infrared temperature images of the injection flame are continuously collected according to a certain sampling frequency, and an infrared temperature image set is obtained for each test.

[0031] S3. Set several temperature recognition thresholds, and extract several temperature distribution curve atlases on the infrared image set according to the temperature recognition thresholds; S31. Set several temperature recognition thresholds according to the actual working conditions; The staff set several temperature recognition thresholds according to actual work experience, such as 1000 °C, 1100 °C, 1200 °C, 1300 °C, 1400 °C, and 1500 °C; It should be noted that the above temperatures are only examples, and the specific settings are determined by the staff according to the actual situation. At the same time, after setting the temperatures, in order to ensure the accuracy of later calculations, a certain floating ratio needs to be set for all temperatures. For example, if it is 5%, the highest temperature recognition threshold will float 5% on the basis of the set value, and the lowest temperature recognition threshold will need to be lowered by 5%; S32. Retrieve the infrared image set and perform gray-scale processing on it to obtain a gray-scale image set of the injection flame; S33. Calibrate the gray-scale values according to each temperature recognition threshold to generate a gray-scale - temperature conversion function; S331. Obtain each temperature recognition threshold and determine the fitting temperature range according to each temperature recognition threshold; First, obtain the temperature recognition threshold set in step S31, and then determine the fitting temperature range for each of the temperature recognition thresholds; for example, the set fitting temperature range is 950°C - 1600°C. S332. Randomly select several test temperatures within the fitting temperature range. Randomly select several temperature values from the set fitting temperature range as test temperatures. It should be noted that the test temperatures are preferably selected according to a certain gradient, for example, selected in increments of 5°C. S333. Control the temperature of the adjustable blackbody furnace to any one of the test temperatures, and capture the infrared temperature image at this test temperature. After the test temperature value is determined, select the first test temperature for testing. Subsequently, adjust the temperature of the adjustable blackbody furnace to this test temperature, and at the same time capture the infrared temperature image at this test temperature through an infrared thermal imager. It should be noted that the infrared thermal imager used in this step is the same device as the infrared thermal imager of the observation module, that is, the observation module is directly used in this step. S334. Calculate the test gray value corresponding to this test temperature according to the infrared temperature image. Extract the captured infrared temperature image, perform gray-scale processing on it to obtain the corresponding gray-scale image, calculate the gray value of this amplitude image, and use this gray value as the test gray value corresponding to this test temperature, that is, obtain a corresponding element group (T1, G1); where T1 represents the test temperature, G1 represents the test gray value, and 1 is the serial number.

[0032] S335. Repeat the step of controlling the temperature of the adjustable blackbody furnace to any one of the test temperatures to obtain all the test gray values. Repeat steps S333 and S334 to obtain a series of test gray values, and at the same time obtain a series of corresponding element groups (T1, G1), (T2, G3),..., (T n , G n ); where n is the parameter serial number. S336. Fit and generate a gray-scale - temperature conversion function according to each of the test temperatures and each of the test gray values.

[0033] First, construct a two-dimensional coordinate system, where the X-axis represents the test temperature and the Y-axis represents the test gray value. According to the element groups (T1, G1), (T2, G3),..., (T n , G n ) in step S335, take points in the two-dimensional coordinate system, and then obtain a fitting curve through computer fitting, and calculate the equation of this fitting curve. This equation is the gray-scale - temperature conversion function. S34, calculating and identifying a grayscale set according to the temperature recognition threshold and the grayscale-temperature conversion function; Obtain all temperature recognition thresholds, and substitute each temperature recognition threshold into the grayscale-temperature conversion function to calculate the recognition grayscale set {G1', G2', G3', ..., G i '}, where i represents the number identifying the grayscale value.

[0034] In the above steps, the blackbody test can be used to calibrate the equipment used in the observation module, thereby eliminating the detection errors of different equipment as much as possible and improving the accuracy of recognition.

[0035] S35. Extracting a temperature distribution curve atlas from the grayscale image set according to the identified grayscale set.

[0036] S351, obtaining any grayscale image from the grayscale image set; S352, dividing the grayscale image into a number of standard cells, and marking the actual grayscale value of each standard cell; Segmenting the grayscale image by longitude and latitude to generate a number of standard cells, where the area of each standard cell is determined based on calculation accuracy requirements, etc., wherein the minimum size of a standard cell is one pixel unit, and the number of standard cells is not less than 10,000; When the division is completed, number each standard cell respectively; At the same time, the grayscale value of each standard cell is obtained, the above grayscale value is used as the actual grayscale value of the standard cell, and the actual grayscale value set {G 11 , G 12 , G 13 ,...,G ab}, where a represents the column number of the standard cell, and b represents the row number of the standard cell; S353, extracting any recognition grayscale value from the recognition grayscale set; S354, extracting all standard cells whose actual grayscale values are equal to the identified grayscale value; Comparing the identified grayscale value with each actual grayscale value, if the actual grayscale value is equal to the identified grayscale value, retaining the corresponding standard cell on the divided grayscale image, otherwise removing the standard cell; After comparing all elements in the actual gray value set, a series of standard cells with a certain distribution pattern will be obtained; S355, connecting the extracted standard cells in series along a clockwise or counterclockwise direction through a curve to obtain an identification temperature distribution curve, and grouping the identified temperature distribution curve into a corresponding temperature distribution curve atlas; First, generate the center point for each standard unit; Then, the center points of each standard cell are connected in series through the curve in a clockwise or counterclockwise direction to obtain the identification temperature distribution curve; The temperature distribution curve is aggregated into a corresponding temperature distribution curve image set according to the temperature value corresponding to the identified gray value; S356, repeating the step of extracting any one identification grayscale value from the identification grayscale set; Repeat steps S351 to S355 to obtain all temperature distribution curves corresponding to the temperature recognition threshold. Based on the principle that one temperature recognition threshold corresponds to one set, a temperature distribution curve can be filled in for each set. S357 , repeat the step of acquiring any grayscale image from the grayscale image set to acquire several temperature distribution curve atlases.

[0037] Repeat steps S351 to S356 to generate a plurality of temperature distribution curve graphs according to each grayscale image in the grayscale image set; Since the jet flame has a certain degree of instability during combustion, that is, the flame will jump, the above method can be used to standardize a series of images of the jet flame during stable combustion, thereby obtaining more comprehensive image information of the flame, avoiding the influence of occasional unexpected factors on data analysis, and thus improving the accuracy and reliability of data analysis.

[0038] S4. Obtaining a plurality of jet flame morphology diagrams according to each of the temperature distribution curve atlases; S41, obtaining any one of the temperature distribution curve atlases; Since each temperature distribution curve in the same temperature distribution curve atlas corresponds to the same temperature recognition threshold, all temperature distribution curves under the temperature recognition threshold can be obtained by extracting the temperature distribution curve atlas; S42, setting a reference point for each temperature distribution curve in the temperature distribution curve atlas; Setting a reference point at the same point on each of the temperature distribution curves, preferably, the reference point is a flame injection port; S43, overlapping the temperature distribution curves according to the reference point to obtain a temperature distribution map; Overlapping the temperature distribution curves according to the reference point, that is, overlapping the projections of the temperature distribution curves in the same direction into the same graph, thereby obtaining a temperature distribution graph; S44, constructing a minimum bounding box about the temperature distribution map, and taking the center line of the minimum bounding box as the jet flame morphology map; Reference Figure 8, generating a minimum bounding box for the temperature distribution map, then randomly generating a number of radial segmentation lines within the minimum bounding box, taking the midpoints of the radial segmentation lines, and connecting the midpoints with a smooth curve; outputting the smooth curve as a jet flame morphology map; The area between the two dotted lines in the figure represents the minimum bounding box, and the dotted line in the middle represents the jet flame morphology diagram; the solid lines in the figure represent the temperature distribution curve; Due to the jumping of the flame, the temperature distribution of the jet flame is in a dynamic change process. However, in the absence of external wind influence, the jumping amplitude of the jet flame is limited, that is, the change of the temperature distribution curve is concentrated in a certain range, which is the minimum bounding box. The temperature distribution range can be accurately delineated by the minimum bounding box, and combined with the center line, the jet flame morphology can be quickly determined while minimizing the detection error and the influence of the jump, thereby improving the accuracy of the jet flame morphology extraction. It should be noted that although the change in the temperature distribution curve caused by flame jumping is a random event, when the external factors are relatively stable, the temperature distribution must satisfy the normal distribution law, that is, a large number of temperature distribution curves will be concentrated in the central area of the minimum bounding box, and the two sides will gradually decrease; based on the above principle, in order to further improve the accuracy of the results, in this step, the temperature distribution curves that obviously deviate from the central area can also be eliminated by manual elimination, thereby reducing the minimum bounding box and improving the accuracy of the jet flame morphology diagram.

[0039] S45. Repeat the acquisition of any one of the temperature distribution curve atlases to obtain a plurality of jet flame morphology diagrams.

[0040] S5. Obtaining jet flame morphology parameters according to the jet flame morphology diagram.

[0041] The jet flame morphology parameters are obtained according to the jet flame morphology diagram, wherein the jet flame morphology parameters include flame length, aspect ratio, etc.

[0042] Compared with the prior art, the present application can input hydrogen-blended natural gas with any blending ratio as needed, which, on the one hand, increases the diversity of the tested hydrogen-blended natural gas and is conducive to improving the accuracy of the test; on the other hand, due to the presence of the temporary storage tank, the temporary storage area and the blending area can be separated from each other, that is, the blending operation can be carried out simultaneously with the injection combustion, and there is no need to switch between different tanks, nor is there a need to prepare a large number of different tanks for storing hydrogen-blended natural gas with different blending ratios, which improves the convenience of equipment operation and makes the equipment respond faster; at the same time, it also reduces the structure of the equipment and improves the reliability and stability of the entire system.

[0043] Meanwhile, the present application produces hydrogen-doped natural gas through on-site blending, which can effectively avoid the excessive production of hydrogen-doped natural gas with a certain blending ratio and improve the utilization rate of the gas.

[0044] The above are only the preferred embodiments of the present application, and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present application, or directly or indirectly applied in other related technical fields, shall be similarly included in the patent protection scope of the present application.

Claims

1. A hydrogen-doped natural gas injection combustion test device, characterized in that, Including: A mixing tank (1) with a mixing module arranged therein; the inlet ends of the mixing module are respectively connected to a hydrogen storage tank (2) and a natural gas storage tank (3); a hydrogen flow meter (4) is further arranged between the mixing module and the hydrogen storage tank (2), and a natural gas flow meter (5) is arranged between the mixing module and the natural gas storage tank (3); A temporary storage tank (6), which is connected to the outlet end of the mixing tank (1) through a pressurizing module; An injection combustion module, which is connected to the temporary storage tank (6); An observation module (8) for collecting infrared temperature images of the injection flame; A controller (9), which is electrically connected to the hydrogen flow meter (4), the natural gas flow meter (5), the pressurizing module and the observation module (8) respectively.

2. The hydrogen-doped natural gas injection combustion test device according to claim 1, wherein The mixing module includes an injection disc (10) and an injection ring (11), the injection disc (10) and the injection ring (11) are coaxially arranged, a first inlet pipe (12) for connecting the hydrogen storage tank (2) is arranged on the injection disc (10), and a second inlet pipe (13) for connecting the natural gas storage tank (3) is arranged on the injection ring (11); a plurality of injection nozzles (14) are arranged on the injection disc (10).

3. The hydrogen-doped natural gas injection combustion test device according to claim 1, characterized in that, An internal circulation pipe (15) is further arranged on the temporary storage tank (6), the inlet end of the internal circulation pipe (15) communicates with the bottom of the temporary storage tank (6), and its outlet end communicates with the top of the temporary storage tank (6); along the gas flow direction, a circulation pump (16) and a mixing module are successively arranged on the internal circulation pipe (15).

4. The hydrogen-doped natural gas injection combustion test device according to claim 3, characterized in that, The mixing module includes a mixing pipe (17), a spiral guide vane (18) coaxial with the mixing pipe (17) is arranged in the mixing pipe (17), a plurality of mixing pins (19) are arranged on the surface of the spiral guide vane (18) in a staggered manner, and the cross section of each mixing pin (19) is arranged in a triangular structure.

5. The hydrogen-doped natural gas injection combustion test device according to claim 1, characterized in that, The injection combustion module includes an injection main pipe (701), a flow distribution disc (702) and a plurality of combustion pipes (703), the outlet end of the injection main pipe (701) communicates with the flow distribution disc (702); the inlet ends of the combustion pipes (703) are respectively communicated with the flow distribution disc (702), and nozzles (704) of the same or different types are arranged at the outlet ends of the combustion pipes (703).

6. The test method of a hydrogen-doped natural gas injection combustion test device according to any one of claims 1-5, characterized in that Including the following steps: Set the mixing ratio, injection pressure and nozzle type of the hydrogen-enriched natural gas as required; Obtain an infrared image set of the injection flame; Set a plurality of temperature recognition thresholds, and extract a plurality of temperature distribution curve atlases on the infrared image set according to the temperature recognition thresholds; Obtain a plurality of injection flame morphology diagrams according to each of the temperature distribution curve atlases; Obtain injection flame morphology parameters according to the injection flame morphology diagrams.

7. The test method according to claim 6, characterized in that, The step of setting a plurality of temperature recognition thresholds and extracting a plurality of temperature distribution curve atlases on the infrared image set according to the temperature recognition thresholds includes the following steps: Set a plurality of temperature recognition thresholds according to the actual working conditions; Retrieving an infrared image set and grayscale processing the image set to obtain a grayscale image set of the jet flame; Grayscale value calibration is performed according to each of the temperature recognition thresholds to generate a grayscale-temperature conversion function; Calculate and identify a grayscale set based on the temperature recognition threshold and the grayscale-temperature conversion function; A temperature distribution curve atlas is extracted from the grayscale image set according to the identified grayscale set.

8. The test method according to claim 7, characterized in that, The grayscale value calibration is performed according to each temperature recognition threshold to generate a grayscale-temperature conversion function, including the following steps: Obtaining each temperature recognition threshold, and determining a fitting temperature range according to each temperature recognition threshold; Randomly select several test temperatures within the fitting temperature range; Control the temperature of the adjustable blackbody furnace to any test temperature and take an infrared temperature image at the test temperature; Calculating a test grayscale value corresponding to the test temperature according to the infrared temperature image; Repeat the steps of controlling the temperature of the adjustable blackbody furnace to any test temperature to obtain all test grayscale values; A grayscale-temperature conversion function is generated by fitting according to each of the test temperatures and each of the test grayscale values.

9. The test method according to claim 7, wherein The step of extracting a temperature distribution curve atlas from the grayscale image set according to the identified grayscale set comprises the following steps: Acquire any grayscale image from the grayscale image set; Dividing the grayscale image into a number of standard cells and marking the actual grayscale value of each standard cell; Extract any recognition grayscale value from the recognition grayscale set; Extracting all standard cells whose actual grayscale values are equal to the identified grayscale values; Connecting the extracted standard cells in series along a clockwise or counterclockwise direction through a curve to obtain an identification temperature distribution curve, and grouping the identified temperature distribution curve into a corresponding temperature distribution curve atlas; Repeat the step of extracting any one identification grayscale value from the identification grayscale set; Repeat the step of acquiring any grayscale image from the grayscale image set to acquire several temperature distribution curve atlases.

10. The test method according to claim 6, wherein The step of obtaining a plurality of jet flame morphology diagrams according to each of the temperature distribution curve atlases comprises the following steps: Obtain any of the temperature distribution curve atlases; Setting a reference point for each temperature distribution curve in the temperature distribution curve atlas; Overlapping the temperature distribution curves according to the reference point to obtain a temperature distribution graph; Constructing a minimum bounding box about the temperature distribution map, and taking the center line of the minimum bounding box as the jet flame morphology map; Repeatedly obtain any of the temperature distribution curve atlases to obtain a plurality of jet flame morphology diagrams.

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