A burner and method for testing the characteristics of a slot effect of an ammonia-hydrogen laminar flow flame

Abstract

The present application relates to the technical field of combustor, disclose a kind of ammonia hydrogen laminar flow flame slit effect characteristic test combustor and test method, including slit nozzle, a pair of slit size adjusting device, a pair of slit size adjusting device support frame and ammonia hydrogen combustion gas mixing chamber;A pair of slit size adjusting device is symmetrically arranged on the corresponding outer side wall of slit nozzle, and a pair of slit size adjusting device can be radially extruded with slit nozzle Touch, adjust the size of slit in slit nozzle;A pair of slit size adjusting device support frame is fixed on the outer side wall of slit nozzle corresponding to a pair of slit size adjusting device, and the corresponding slit size adjusting device is fixed by sleeve joint;Ammonia hydrogen combustion gas mixing chamber is fixedly connected with slit nozzle by bolt;The present application can study ammonia hydrogen laminar flow flame slit effect, solve the engineering problem whether ammonia hydrogen fuel can be stably combusted in narrow space, and provide basis for equipment design by quantifying key characteristic parameters.

Description

Technical Field

[0001] This invention relates to the field of burner technology, and in particular to a burner and test method for testing the slit effect characteristics of ammonia-hydrogen laminar flame. Background Technology

[0002] The proposed goals of "carbon peaking and carbon neutrality" have further raised the requirements for clean and low-carbon combustion. Ammonia (NH3) is a potential "zero-carbon fuel" under the background of carbon neutrality, but pure ammonia combustion has problems such as slow flame propagation speed and difficulty in ignition. Hydrogen (H2) is a highly reactive fuel that can improve the combustion performance of ammonia. Therefore, "ammonia-hydrogen mixture" is often used in practical applications. Ammonia-hydrogen as a zero-carbon fuel has been valued by society and scientific research fields, and its promotion and application is expected to become an important technical approach for the transportation industry to achieve the "dual carbon" goal.

[0003] The widespread application of ammonia-hydrogen fuel cannot be separated from the clarification of its basic combustion characteristics. Flames are classified into "laminar" and "turbulent" types: laminar flames have stable flow, a clear flame front (the interface between the combustion zone and the unburned zone), and stable combustion parameters (such as flame propagation speed), making them the "standard state" for studying the basic combustion characteristics of fuels (turbulent flames are greatly affected by disturbances and are not suitable for testing basic characteristics). A "slit channel" refers to a narrow space whose width is much smaller than its length (e.g., 0.1-5 mm wide and tens of millimeters long). When a flame burns in such a channel, it is subject to the dual effects of geometric constraints and increased heat loss, resulting in the "slit effect." For example, the flame propagation speed decreases, the flame front deforms, and the flame may even extinguish due to excessive heat loss. This effect simulates the scenario of a "narrow combustion space" in actual equipment (such as the combustion chamber of a micro gas turbine, the auxiliary burner of a fuel cell, the gap between the engine piston and the cylinder). In practical applications, the slit effect of laminar flame formation in the early stage of ammonia-hydrogen fuel combustion plays a crucial role in improving the combustion efficiency and emission cleanliness of power plants. Therefore, designing and developing a burner to explore the combustion characteristics of the ammonia-hydrogen slit effect can provide an effective research device for the study of the slit effect of ammonia-hydrogen combustion. Summary of the Invention

[0004] To address the aforementioned issues, this invention provides a burner for testing the slit effect characteristics of ammonia-hydrogen laminar flames. This burner can study the slit effect of ammonia-hydrogen laminar flames, solve the engineering problem of whether ammonia-hydrogen fuel can burn stably in a narrow space, and provide a basis for equipment design by quantifying key characteristic parameters.

[0005] This invention proposes a burner for testing the slit effect characteristics of an ammonia-hydrogen laminar flame, comprising a slit nozzle, a pair of slit size adjustment devices, a pair of slit size adjustment device support frames, and an ammonia-hydrogen combustion gas mixing chamber;

[0006] A pair of slit size adjustment devices are symmetrically arranged on the corresponding outer wall of the slit nozzle, and the pair of slit size adjustment devices can radially press against the slit nozzle to adjust the size of the slit in the slit nozzle. By precisely adjusting the size of the slit nozzle through the slit size adjustment devices, the parameters of the ammonia-hydrogen laminar flow flame passing through slits of different sizes can be obtained.

[0007] A pair of slit size adjustment device support frames are fixed on the outer wall of the slit nozzle for a pair of slit size adjustment devices, and the corresponding slit size adjustment devices are sleeved and fixed.

[0008] The ammonia-hydrogen combustion gas mixing chamber is fixedly connected to the slit nozzle by bolts. The ammonia-hydrogen combustion gas mixing chamber can provide the slit nozzle with the laminar flame for initial combustion. The slit nozzle is made of flexible metal assembly and is used to simulate the slit and gap between the piston and cylinder liner when ammonia-hydrogen fuel is used in actual engines, in order to explore the slit effect of ammonia-hydrogen fuel.

[0009] The slit nozzle is made of a high-temperature resistant, non-memory metal. It can deform under external force and return to its original shape when the force is removed. The slit nozzle includes a metal tubular outer cavity, several flexible metal rings, and a flexible metal core. The flexible metal rings are concentrically connected and suspended in the upper part of the metal tubular outer cavity, and the flexible metal core is concentrically suspended and fixed within the innermost flexible metal ring. The flexible metal core, each flexible metal ring, and the inner wall of the metal tubular outer cavity are all adjacent to each other, forming an annular slit between each pair. The flexible metal core and the flexible metal rings are divided into two halves along the same diameter of the metal tubular outer cavity. The two halves of the flexible metal core and each flexible metal ring can elastically deform outwards under the pressure of the slit size adjustment device at the two side joints, changing the size of the slit space. Two symmetrical slot size adjustment device insertion holes are provided on the side wall of the tubular outer cavity corresponding to the joints of the two halves of the flexible metal ring. The front cones of the pair of slot size adjustment devices are respectively housed in the corresponding slot size adjustment device insertion holes. The front cones of the pair of slot size adjustment devices can respectively press and contact the joints on both sides of the flexible metal ring composed of two halves and the joints on both sides of the flexible metal core composed of two halves. An outer cavity wall expansion slot is provided on the upper edge of the side wall of the tubular outer cavity corresponding to the joints of the two halves of the flexible metal ring from the two slot size adjustment device insertion holes to the joints of the two halves of the flexible metal ring. This is to adjust the size of the slots between the two halves of the flexible metal core, between the outer wall of the flexible metal core and the inner wall of the flexible metal ring, between the side walls of the two flexible metal rings, and between the outer wall of the flexible metal ring and the inner wall of the tubular outer cavity, so as to test the characteristics of different slit effects of laminar flames.

[0010] The slit size adjustment device is a micrometer. The micrometer screw at the front end of the micrometer is a cone with an acute triangular cross-section. The cone at the micrometer screw end can be retracted and accommodated in the insertion hole of the slit size adjustment device. By adjusting the micrometer, the slit size can be flexibly and precisely adjusted. To achieve precise adjustment, the slit device needs a tapered set screw structure at the front for fine adjustment of the distance of the metal sheet, thus achieving precise fine adjustment of the slit size. Two micrometer structures are designed and installed at 180° opposite each other at both ends of the slit nozzle to achieve uniform adjustment of the overall size of the slit structure and prevent offset during the adjustment process.

[0011] The slit size adjustment device support frame includes an L-shaped bracket. The horizontal arm of the L-shaped bracket is vertically fixed to the lower part of the outer wall of the metal tubular outer cavity. The upper end of the vertical arm of the L-shaped bracket is provided with a horizontal sleeve. The micrometer screw at the front of the micrometer is slidably sleeved in the horizontal sleeve.

[0012] Several flexible metal rings have their lower ends located in the middle of the inner wall of a metal tubular outer cavity. A horizontal beam perpendicular to the radial line of the joint between the two halves of the flexible metal rings is fixedly connected to the lower end face of each flexible metal ring consisting of two halves. Both ends of the horizontal beam are embedded and fixed to the side wall of the metal tubular outer cavity. The flexible metal rings consisting of two halves are suspended above the interior of the metal tubular outer cavity by this horizontal beam. Since the bottom ends of the arcs of the two halves of each flexible metal ring are fixedly connected to the horizontal beam, the arcs of the two halves of each flexible metal ring are subject to a slit size adjustment device. The front conical part is squeezed, and the two ends of the semi-circular arc will deform and open, changing the size of the slit space. The lower part of the joint between the two halves of each flexible metal ring and the lower part of the joint between the two halves of the flexible metal core are respectively provided with arc surfaces at the forward stroke position of the conical part at the end of the micrometer screw of the two micrometers. The arc surfaces formed by the arc surfaces on one side of several flexible metal rings, the arc surfaces on one side of flexible metal core, and the slit size adjustment device insertion hole on one side of the metal tubular outer cavity can be squeezed and contacted in a way that matches the shape of the upper side wall of the conical part at the end of the micrometer screw of the corresponding position.

[0013] Several flexible metal rings are located at the lower end of the inner wall of the outer cavity of the metal tubular body. The inner and outer walls of the arc apex of the two halves of each flexible metal ring are fixedly connected to the inner wall of the adjacent outer cavity of the metal tubular body, the arc surfaces of the two halves of the flexible metal ring, and the outer wall of the flexible metal core composed of the two halves through metal welding blocks. Several flexible metal rings composed of two halves are suspended above the inner cavity of the metal tubular body through several metal welding blocks. The lower part of the joint between the two halves of each flexible metal ring and the lower part of the joint between the two halves of the flexible metal core are respectively provided with arc surfaces corresponding to the forward stroke position of the conical end of the micrometer screw of the two micrometers. The arc surfaces formed by the arc surfaces on one side of the several flexible metal rings, the arc surfaces on one side of the flexible metal core, and the slit size adjustment device insertion hole on one side of the metal tubular body can be pressed and contacted with the upper side wall of the conical end of the micrometer screw of the corresponding position.

[0014] The lower ends of several flexible metal rings are flush with the lower end face of the metal tubular outer cavity. A horizontal beam perpendicular to the radial line of the joint between the two halves of the flexible metal rings is fixedly connected to the lower end face of each flexible metal ring consisting of two halves. The two ends of the horizontal beam are welded and fixed to the lower end of the inner wall of the metal tubular outer cavity. The flexible metal rings consisting of several halves are suspended inside the metal tubular outer cavity through the horizontal beam. The middle part of the joint between the two halves of each flexible metal ring and the middle part of the joint between the two halves of the flexible metal core are respectively provided with arc surfaces at the forward stroke positions of the conical ends of the micrometer screws of the two micrometers. The conical cavity formed by the arc surfaces on one side of the several flexible metal rings, the arc surfaces on one side of the flexible metal core, and the slit size adjustment device insertion holes on one side of the metal tubular outer cavity can be squeezed and contacted in a way that matches the shape of the conical sidewall of the micrometer screw end at the corresponding position.

[0015] The ammonia-hydrogen combustion gas mixing chamber includes a cylindrical body with an open top, an ammonia-hydrogen fuel mixer inlet, and an oxidant inlet. The upper edge of the cylindrical body with the open top is bolted to the lower end face of a metal tubular outer cavity. The ammonia-hydrogen fuel mixer inlet is fixed to the middle of the lower bottom surface of the cylindrical body with the open top, and the oxidant inlet is fixed to the lower part of the side wall of the cylindrical body with the open top. The ammonia-hydrogen combustion gas mixing chamber is used to quantitatively and continuously introduce ammonia-hydrogen fuel and oxidant, precisely controlled by a matching optical path and mass flow meter, into the combustion chamber to ensure a continuous and stable supply of fuel and oxidant required by the combustion chamber. To achieve laminar flame combustion, an air inlet mixing chamber is provided at the bottom of the slit nozzle to achieve uniform mixing of ammonia fuel and hydrogen fuel and combustion at the slit.

[0016] A test method, applied to the aforementioned ammonia-hydrogen laminar flame slit effect characteristic test burner, comprises the following steps:

[0017] S1. When using the ammonia-hydrogen laminar flame slit effect characteristic test burner, it is necessary to install a complete set of slit nozzles, a pair of slit size adjustment devices, a pair of slit size adjustment device support frames, and ammonia-hydrogen combustion gas mixing chambers. After installation, the airtightness of the entire system must be checked first to ensure that the burner does not overflow from any position other than the head of the slit nozzle during combustion.

[0018] S2. After installation and airtightness check, the structural position and slit size of the slit size adjustment device need to be calibrated. After tightening the position of the slit size adjustment device, the distance between the adjustment size of the slit size adjustment device and the slit size needs to be calibrated to clarify the functional correspondence between the advance amount of the slit size adjustment device and the slit size.

[0019] S3 connects the ammonia-hydrogen gas path and the oxidizer pipeline, forming a combustible mixture in the ammonia-hydrogen combustion gas mixing chamber, thereby achieving the combustion of the slit-effect flame, and ultimately testing the slit-effect characteristics of the ammonia-hydrogen flame.

[0020] Changes in temperature and humidity in the test environment mentioned above (S1) may cause thermal expansion and contraction and deformation of the material, affecting the measurement results; therefore, the temperature of the test environment is controlled at 20℃±2℃, and the relative humidity of the test environment is controlled at 40%-60%.

[0021] The above S2 requires the following operations to calibrate the structural position and slit size of the slit size adjustment device: calibrate the micrometer's adjustment scale to zero, check the micrometer's working status to ensure its screw rotates flexibly, the scale is clear, and there is no jamming; perform zero-point calibration on the micrometer to avoid initial errors; when the micrometer is at zero, use a high-precision laser displacement sensor to measure the distance between the slits, measure three times consecutively, and record the slit distance when the micrometer is at zero.

[0022] The functional relationship between the advance amount of the slit size adjustment device and the slit size, as specified in S2 above, requires the following operation: make a micrometer adjustment in increments of 0.01 mm, and after each adjustment, wait 1-2 minutes to allow the slit size to stabilize and eliminate the influence of factors such as elastic deformation generated during the adjustment process;

[0023] The slit size is measured using a high-precision laser displacement sensor. The probe of the laser displacement sensor is accurately aligned with the position of the slit to ensure the accuracy of the measurement. Similarly, the slit size at each adjustment position is measured at least three times and the average value is taken.

[0024] Record each micrometer adjustment reading and the corresponding slit size;

[0025] Repeat the above steps, making multiple adjustments and measurements, generally no less than 10 sets of data; the adjustment range should cover the slit size required for the test;

[0026] Organize the recorded data into a table, listing the micrometer readings and the corresponding slit dimensions;

[0027] Plot a scatter plot with the micrometer advance as the independent variable and the slit size change as the dependent variable.

[0028] The least squares method was used to perform a linear fit on the scatter plot to obtain the linear regression equation;

[0029] Perform a significance test on the fitted function to ensure that the function is statistically significant;

[0030] Finally, a set of data points that were not involved in the fitting were selected, and the slit size was calculated using the fitted function relationship. The result was then compared with the actual measured value. If the error between the calculated value and the measured value was within ±0.005 mm, the function relationship was considered reliable.

[0031] Throughout the calibration process, avoid applying additional external force to the micrometer and slit device to prevent affecting the measurement results; before each measurement, ensure that the measuring surfaces of the measuring tools are clean and free of impurities and oil.

[0032] Beneficial effects

[0033] This invention enables flexible adjustment of the slit size, allowing for the study of the slit effect in ammonia-hydrogen laminar flames, solving the engineering problem of whether ammonia-hydrogen fuel can burn stably in a narrow space, and providing a basis for equipment design by quantifying key characteristic parameters. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0035] Figure 2 This is a side view of the structure of the present invention.

[0036] Figure 3 yes Figure 2 A schematic diagram of the AA-direction cross-sectional structure.

[0037] Figure 4 This is a schematic diagram of the front structure of the present invention.

[0038] Figure 5 yes Figure 4 A schematic diagram of the BB-oriented structure.

[0039] Figure 6 This is a schematic diagram of the three-dimensional structure of the slit nozzle of the present invention.

[0040] Figure 7 This is a three-dimensional structural diagram of the slit nozzle of the present invention viewed from below.

[0041] Figure 8This is a cross-sectional structural diagram of Embodiment 2 of the present invention.

[0042] Figure 9 This is a cross-sectional structural diagram of Embodiment 3 of the present invention.

[0043] In the picture:

[0044] 1. Slit nozzle; 11. Metal tubular outer cavity; 111. Slit size adjustment device insertion hole; 112. Expansion joint in outer cavity wall; 12. Flexible metal ring; 121. Arc surface; 13. Flexible metal core;

[0045] 2. Slit size adjustment device; 21. Micrometer screw;

[0046] 3. Slit size adjustment device support frame; 31. L-shaped bracket; 32. Horizontal sleeve;

[0047] 4. Ammonia-hydrogen combustion gas mixing chamber; 41. Top-opening cylinder; 42. Ammonia-hydrogen fuel mixer inlet; 43. Oxidant inlet.

[0048] 5. Horizontal beam;

[0049] 6. Metal welded blocks. Detailed Implementation

[0050] To make the technical problems solved by the present invention, the technical solutions adopted, and the technical effects achieved clearer, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention. Furthermore, it should be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings, not all of them.

[0051] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0052] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0053] Example 1

[0054] See Figures 1-7 As shown, a burner for testing the slit effect characteristics of an ammonia-hydrogen laminar flame includes a slit nozzle 1, a pair of slit size adjustment devices 2, a pair of slit size adjustment device support frames 3, and an ammonia-hydrogen combustion gas mixing chamber 4.

[0055] A pair of slit size adjustment devices 2 are symmetrically arranged on the corresponding outer side wall of the slit nozzle 1, and the pair of slit size adjustment devices 2 can radially press and contact the slit nozzle 1 to adjust the size of the slit in the slit nozzle 1;

[0056] A pair of slit size adjustment device support frames 3 are fixed on the outer wall of the slit nozzle 1, corresponding to a pair of slit size adjustment devices 2, and the corresponding slit size adjustment devices 2 are sleeved and fixed.

[0057] The ammonia-hydrogen combustion gas mixing chamber 4 is fixedly connected to the slit nozzle 1 by bolts.

[0058] The slit nozzle 1 is made of a high-temperature resistant, non-memory metal. The slit nozzle 1 includes a metal tubular outer cavity 11, four flexible metal rings 12, and a flexible metal core 13. The four flexible metal rings 12 are concentrically connected and suspended and fixed in the upper part of the metal tubular outer cavity 11. The flexible metal core 13 is concentrically suspended and fixed in the innermost flexible metal ring 12. The flexible metal core 13, each flexible metal ring 12, and the inner wall of the metal tubular outer cavity 11 are all adjacent to each other, forming an annular slit between each pair. The flexible metal core 13 and the four flexible metal rings 12 are divided into two halves along the same diameter direction of the metal tubular outer cavity 11. Two symmetrical slit size adjustment device insertion holes 111 are provided on the side wall of the outer cavity 11 corresponding to the joint of the two halves of the flexible metal ring 12. The front cones of a pair of slit size adjustment devices 2 are respectively housed in the corresponding slit size adjustment device insertion holes 111. The front cones of the pair of slit size adjustment devices 2 can respectively press and contact the joints on both sides of the flexible metal ring 12 composed of two halves and the joints on both sides of the flexible metal core 13 composed of two halves. An outer cavity wall expansion slit 112 is provided from the two slit size adjustment device insertion holes 111 to the upper edge of the side wall of the metal tubular outer cavity 11 corresponding to the joint of the two halves of the flexible metal ring 12.

[0059] The slit size adjustment device 2 is a micrometer. The end of the micrometer screw 21 at the front end of the micrometer is a cone with an acute triangular cross section. The cone at the end of the micrometer screw 21 can be extended and accommodated in the insertion hole 111 of the slit size adjustment device.

[0060] The slit size adjustment device support frame 3 includes an L-shaped bracket 31. The horizontal arm of the L-shaped bracket 31 is vertically fixed to the lower part of the outer wall of the metal tubular outer cavity 11. The upper end of the vertical arm of the L-shaped bracket 31 is provided with a horizontal sleeve 32. The micrometer screw 21 at the front of the micrometer is slidably sleeved in the horizontal sleeve 32.

[0061] The lower ends of four flexible metal rings 12 are located in the middle of the inner wall of the metal tubular outer cavity 11. A horizontal beam 5, perpendicular to the radial line of the joint between the two halves of the four flexible metal rings 12, is fixedly connected to the lower end face of each flexible metal ring 12 composed of two halves. The two ends of the horizontal beam 5 are embedded and fixed to the side wall of the metal tubular outer cavity 11. The four flexible metal rings 12 composed of two halves are suspended above the interior of the metal tubular outer cavity through the horizontal beam 5. The lower part of the joint between the two halves of each flexible metal ring 12 is... The lower part of the joint between the two halves of the flexible metal core 13 is provided with an arc surface 121 corresponding to the forward stroke position of the conical end of the micrometer screw 21 of the two micrometers. The arc surface formed by the arc surface 121 on one side of the four flexible metal rings 12, the arc surface 121 on one side of the flexible metal core 13, and the slit size adjustment device insertion hole 111 on one side of the metal tubular outer cavity 11 can be pressed and contacted with the upper side wall of the conical end of the micrometer screw 21 at the corresponding position.

[0062] The ammonia-hydrogen combustion gas mixing chamber 4 includes a cylindrical body 41 with an open top, an ammonia-hydrogen fuel mixer inlet 42, and an oxidant inlet 43. The upper edge of the cylindrical body 41 with an open top is connected to the lower end face of the metal tubular outer cavity 11 by bolts. The ammonia-hydrogen fuel mixer inlet 42 is inserted and fixed to the middle of the lower bottom surface of the cylindrical body 41 with an open top, and the oxidant inlet 43 is inserted and fixed to the lower part of the side wall of the cylindrical body 41 with an open top.

[0063] Example 2

[0064] See Figure 1 , Figure 6 and Figure 9As shown, a burner for testing the slit effect characteristics of ammonia-hydrogen laminar flame differs from Embodiment 1 in that the lower ends of the four flexible metal rings 12 are located in the middle of the inner wall of the metal tubular outer cavity 11. The inner and outer walls of the arc apex of the two halves of each flexible metal ring 12 are fixedly connected to the inner wall of the adjacent metal tubular outer cavity 11, the arc surface of the two halves of the flexible metal ring 12, and the outer wall of the flexible metal core 13 formed by the two halves, respectively, through metal welding blocks 6. The four flexible metal rings 12 formed by the two halves are suspended in the metal tubular outer cavity by ten metal welding blocks 6. Inside, at the top, the lower part of the joint between the two halves of each flexible metal ring 12 and the lower part of the joint between the two halves of the flexible metal core 13 are respectively provided with arc surfaces 121 corresponding to the forward stroke position of the conical end of the micrometer screw 21 of the two micrometers. The arc surfaces formed by the arc surfaces 121 on one side of the four flexible metal rings 12, the arc surfaces 121 on one side of the flexible metal core 13, and the slit size adjustment device insertion hole 111 on one side of the metal tubular outer cavity 11 can be pressed and contacted with the upper side wall of the conical end of the micrometer screw 21 at the corresponding position.

[0065] Example 3

[0066] See Figure 1 , Figure 6 and Figure 8 As shown, a burner for testing the slit effect characteristics of an ammonia-hydrogen laminar flame differs from Embodiment 1 in that the lower ends of four flexible metal rings 12 are flush with the lower end face of the metal tubular outer cavity 11. A horizontal beam 5, perpendicular to the radial line of the joint between the two halves of the four flexible metal rings 12, is fixedly connected to the lower end face of each flexible metal ring 12 composed of two halves. The two ends of the horizontal beam 5 are welded and fixed to the lower end of the inner wall of the metal tubular outer cavity 11. The four flexible metal rings 12 composed of two halves are suspended inside the metal tubular outer cavity through the horizontal beam 5. The middle part of the joint between the two halves of the flexible metal ring 12 and the middle part of the joint between the two halves of the flexible metal core 13 are respectively provided with arc surfaces 121 at the conical forward movement positions of the ends of the micrometer screws 21 of the two micrometers. The conical accommodating cavity formed by the arc surfaces 121 on one side of the four flexible metal rings 12, the arc surfaces 121 on one side of the flexible metal core 13, and the slit size adjustment device insertion hole 111 on one side of the metal tubular outer cavity 11 can be squeezed and contacted in a way that matches the shape of the conical sidewall of the end of the micrometer screw 21 of the micrometer at the corresponding position.

[0067] Example 4

[0068] See Figures 1-7 As shown, a test method is applied to a burner for testing the slit effect characteristics of an ammonia-hydrogen laminar flame. The steps are as follows:

[0069] S1. When using the ammonia-hydrogen laminar flame slit effect characteristic test burner, it is necessary to install a complete set of slit nozzles 1, a pair of slit size adjustment devices 2, a pair of slit size adjustment device support frames 3, and ammonia-hydrogen combustion gas mixing chamber 4. After installation, the airtightness of the entire system should be checked first to ensure that the burner does not overflow from any position other than the head of the slit nozzle 1 during combustion.

[0070] S2. After installation and airtightness check, the structural position and slit size of the slit size adjustment device 2 need to be calibrated. After tightening the position of the slit size adjustment device 2, the distance between the adjustment size of the slit size adjustment device 2 and the slit size needs to be calibrated to clarify the functional correspondence between the advance amount of the slit size adjustment device 2 and the slit size.

[0071] S3 connects the ammonia-hydrogen gas path and the oxidizer pipeline, forming a combustible mixture in the ammonia-hydrogen combustion gas mixing chamber 4, thereby achieving the combustion of the slit effect flame, and finally realizing the test of the slit effect characteristics of the ammonia-hydrogen flame.

[0072] Changes in temperature and humidity in the test environment mentioned above (S1) may cause thermal expansion and contraction and deformation of the material, affecting the measurement results; therefore, the temperature of the test environment is controlled at 20℃±2℃, and the relative humidity of the test environment is controlled at 40%-60%.

[0073] The following operations are required to calibrate the structural position and slit size of the slit size adjustment device 2 in S2 above: calibrate the micrometer's fine adjustment scale to zero, check the micrometer's working status to ensure that its screw rotates flexibly, the scale is clear, and there is no jamming; perform zero-point calibration on the micrometer to avoid initial errors; when the micrometer is at zero, use a high-precision laser displacement sensor to measure the distance between the slits, measure three times consecutively, and record the slit distance when the micrometer is at zero.

[0074] The functional relationship between the advance amount of the slit size adjustment device 2 and the slit size, as specified in S2 above, requires the following operation: make a micrometer adjustment in increments of 0.01 mm, and after each adjustment, wait 1-2 minutes to allow the slit size to stabilize and eliminate the influence of factors such as elastic deformation generated during the adjustment process;

[0075] The slit size is measured using a high-precision laser displacement sensor. The probe of the laser displacement sensor is accurately aligned with the position of the slit to ensure the accuracy of the measurement. Similarly, the slit size at each adjustment position is measured at least three times and the average value is taken.

[0076] Record each micrometer adjustment reading and the corresponding slit size;

[0077] Repeat the above steps, making multiple adjustments and measurements, generally no less than 10 sets of data; the adjustment range should cover the slit size required for the test;

[0078] Organize the recorded data into a table, listing the micrometer readings and the corresponding slit dimensions;

[0079] Plot a scatter plot with the micrometer advance as the independent variable and the slit size change as the dependent variable.

[0080] The least squares method was used to perform a linear fit on the scatter plot to obtain the linear regression equation;

[0081] Perform a significance test on the fitted function to ensure that the function is statistically significant;

[0082] Finally, a set of data points that were not involved in the fitting were selected, and the slit size was calculated using the fitted function relationship. The result was then compared with the actual measured value. If the error between the calculated value and the measured value was within ±0.005 mm, the function relationship was considered reliable.

[0083] Throughout the calibration process, avoid applying additional external force to the micrometer and slit device to prevent affecting the measurement results; before each measurement, ensure that the measuring surfaces of the measuring tools are clean and free of impurities and oil.

[0084] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A burner for testing the slit effect characteristics of an ammonia-hydrogen laminar flame, characterized in that: It includes a slit nozzle (1), a pair of slit size adjustment devices (2), a pair of slit size adjustment device support frames (3), and an ammonia-hydrogen combustion gas mixing chamber (4); A pair of slit size adjustment devices (2) are symmetrically arranged on the corresponding outer wall of the slit nozzle (1), and the pair of slit size adjustment devices (2) can be radially pressed into contact with the slit nozzle (1) to adjust the size of the slit in the slit nozzle (1); A pair of slit size adjustment device support frames (3) are fixed on the outer wall of the slit nozzle (1) corresponding to a pair of slit size adjustment devices (2), and the corresponding slit size adjustment devices (2) are sleeved and fixed. The ammonia-hydrogen combustion gas mixing chamber (4) is fixedly connected to the slit nozzle (1) by bolts; The slit nozzle (1) is made of high-temperature resistant non-memory metal. The slit nozzle (1) includes a metal tubular outer cavity (11), several flexible metal rings (12), and a flexible metal core (13). The several flexible metal rings (12) are concentrically connected and suspended and fixed in the upper part of the metal tubular outer cavity (11). The flexible metal core (13) is concentrically suspended and fixed in the innermost flexible metal ring (12). The flexible metal core (13), each flexible metal ring (12), and the inner wall of the metal tubular outer cavity (11) are all adjacent to each other, forming an annular slit between each pair. The flexible metal core (13) and several flexible metal rings (12) are decomposed into two halves along the same diameter direction of the metal tubular outer cavity (11). Two symmetrical slot size adjustment device insertion holes (111) are provided on the side wall of the metal tubular outer cavity (11) corresponding to the joint of the two halves of the flexible metal ring (12). The front cones of a pair of slot size adjustment devices (2) are respectively housed in the slot size adjustment device insertion holes (111) at the corresponding positions. The front cones of the pair of slot size adjustment devices (2) can be pressed and contacted with the joints on both sides of the flexible metal ring (12) composed of two halves and the joints on both sides of the flexible metal core (13) composed of two halves. An outer cavity wall expansion slit (112) is provided from the two slot size adjustment device insertion holes (111) to the upper edge of the side wall of the metal tubular outer cavity (11) corresponding to the joint of the two halves of the flexible metal ring (12).

2. The ammonia-hydrogen laminar flame slit effect characteristic tester according to claim 1, characterized in that: The slit size adjustment device (2) is a micrometer. The end of the micrometer screw (21) at the front end of the micrometer is a cone, and the cross section of the cone is an acute triangle. The cone at the end of the micrometer screw (21) can be extended and accommodated in the slit size adjustment device insertion hole (111).

3. The ammonia-hydrogen laminar flame slit effect characteristic tester according to claim 2, characterized in that: The slit size adjustment device support frame (3) includes an L-shaped bracket (31), the horizontal arm of which is vertically fixed to the lower part of the outer wall of the metal tubular outer cavity (11), and a horizontal sleeve (32) is provided at the upper end of the vertical arm of the L-shaped bracket (31). The micrometer screw (21) at the front of the micrometer is slidably sleeved in the horizontal sleeve (32).

4. The ammonia-hydrogen laminar flame slit effect characteristic tester according to claim 3, characterized in that: Several flexible metal rings (12) have their lower ends located in the middle of the inner wall of the metal tubular outer cavity (11). A horizontal beam (5) perpendicular to the radial line of the joint between the two halves of the flexible metal rings (12) is fixedly connected to the lower end face of each flexible metal ring (12) consisting of two halves. The two ends of the horizontal beam (5) are embedded and fixed on the side wall of the metal tubular outer cavity (11). The flexible metal rings (12) consisting of two halves are suspended above the inside of the metal tubular outer cavity through the horizontal beam (5). The lower part of the joint between the two halves of each flexible metal ring (12) is... The lower part of the joint between the two halves of the flexible metal core (13) is provided with an arc surface (121) corresponding to the forward stroke position of the conical part at the end of the micrometer screw (21) of the two micrometers. The arc surface formed by the arc surface (121) on one side of several flexible metal rings (12), the arc surface (121) on one side of the flexible metal core (13), and the slit size adjustment device insertion hole (111) on one side of the metal tubular outer cavity (11) can be squeezed and contacted in a way that matches the shape of the upper side wall of the conical part at the end of the micrometer screw (21) of the corresponding position.

5. The ammonia-hydrogen laminar flame slit effect characteristic tester according to claim 3, characterized in that: Several flexible metal rings (12) are located at the middle of the inner wall of the metal tubular outer cavity (11) at their lower ends. The inner and outer walls of the arc apex of the two halves of each flexible metal ring (12) are fixedly connected to the inner wall of the adjacent metal tubular outer cavity (11), the arc surface of the two halves of the flexible metal ring (12), and the outer wall of the flexible metal core (13) formed by the two halves through metal welding blocks (6). Several flexible metal rings (12) formed by two halves are suspended above the inside of the metal tubular outer cavity through several metal welding blocks (6). The two halves of each flexible metal ring (12) are connected to the inner wall of the metal tubular outer cavity. The lower part of the seam and the lower part of the joint between the two halves of the flexible metal core (13) are respectively provided with arc surfaces (121) at the forward stroke position of the conical body at the end of the micrometer screw (21) of the two micrometers. The arc surfaces (121) on one side of several flexible metal rings (12), the arc surfaces (121) on one side of the flexible metal core (13) and the slit size adjustment device insertion hole (111) on one side of the metal tubular outer cavity (11) can be squeezed and contacted in a way that matches the shape of the upper side wall of the conical body at the end of the micrometer screw (21) of the corresponding position.

6. The ammonia-hydrogen laminar flame slit effect characteristic tester according to claim 3, characterized in that: The lower ends of several flexible metal rings (12) are flush with the lower end face of the metal tubular outer cavity (11). A horizontal beam (5) perpendicular to the radial line of the joint between the two halves of the flexible metal rings (12) is fixedly connected to the lower end face of each flexible metal ring (12) consisting of two halves. The two ends of the horizontal beam (5) are welded and fixed to the lower end of the inner wall of the metal tubular outer cavity (11). The flexible metal rings (12) consisting of two halves are suspended inside the metal tubular outer cavity through the horizontal beam (5). The middle part of the joint between the two halves of each flexible metal ring (12) and The two halves of the flexible metal core (13) are joined together at the middle part, which corresponds to the conical stroke position of the end of the micrometer screw (21) of the two micrometers. The conical cavity formed by the conical surface (121) on one side of several flexible metal rings (12), the conical surface (121) on one side of the flexible metal core (13), and the slit size adjustment device insertion hole (111) on one side of the metal tubular outer cavity (11) can be squeezed and contacted with the conical sidewall of the end of the micrometer screw (21) of the corresponding position.

7. A burner for testing the slit effect characteristics of an ammonia-hydrogen laminar flame according to any one of claims 4-6, characterized in that: The ammonia-hydrogen combustion gas mixing chamber (4) includes a cylinder (41) with an open top, an ammonia-hydrogen fuel mixer inlet (42), and an oxidant inlet (43). The upper edge of the cylinder (41) with an open top is connected to the lower end face of the metal tubular outer cavity (11) by bolts. The ammonia-hydrogen fuel mixer inlet (42) is inserted and fixed to the middle of the lower bottom surface of the cylinder (41) with an open top, and the oxidant inlet (43) is inserted and fixed to the lower part of the side wall of the cylinder (41) with an open top.

8. A test method applied to a burner for testing the slit effect characteristics of an ammonia-hydrogen laminar flame as described in any one of claims 1-7, characterized in that, The steps are as follows: S1. When using the ammonia-hydrogen laminar flame slit effect characteristic test burner, it is necessary to install a complete set of slit nozzles (1), a pair of slit size adjustment devices (2), a pair of slit size adjustment device support frames (3), and ammonia-hydrogen combustion gas mixing chamber (4). After installation, the air tightness of the entire system should be checked first to ensure that the burner does not overflow from any position other than the head of the slit nozzle (1) during combustion. The temperature and humidity of the test environment should be controlled within a certain range. S2. After installation and airtightness check, the structural position and slit size of the slit size adjustment device (2) need to be calibrated. After tightening the position of the slit size adjustment device (2), the distance between the adjustment size of the slit size adjustment device (2) and the slit size needs to be calibrated to clarify the functional correspondence between the advance amount of the slit size adjustment device (2) and the slit size. S3 connects the ammonia-hydrogen gas path and the oxidizer pipeline, forming a combustible mixture in the ammonia-hydrogen combustion gas mixing chamber (4), thereby achieving the combustion of the slit effect flame, and finally realizing the test of the slit effect characteristics of the ammonia-hydrogen flame.

9. The test method according to claim 8, characterized in that: In S1, the temperature of the test environment is controlled at 20℃±2℃, and the relative humidity of the test environment is controlled at 40% - 60%. The following operations are required to calibrate the structure position and slit size of the slit size adjustment device (2) in S2: calibrate the micrometer's micro-adjustment scale to zero, check the working status of the micrometer, ensure that its screw rotates flexibly, the scale is clear, and there is no jamming, and calibrate the micrometer to zero position to avoid initial error; when the micrometer is zero, use a high-precision laser displacement sensor to measure the distance between the slits, measure three times in a row, and record the distance between the slits when the micrometer is zero. S2 clearly defines the functional relationship between the advance amount and the slit size of the slit size adjustment device (2). The following operations are required: make a micrometer adjustment of 0.01mm. After each adjustment, wait 1-2 minutes to allow the slit size to stabilize and eliminate the influence of factors such as elastic deformation generated during the adjustment process. The slit size is measured using a high-precision laser displacement sensor. The probe of the laser displacement sensor is accurately aligned with the position of the slit to ensure the accuracy of the measurement. Similarly, the slit size at each adjustment position is measured at least three times and the average value is taken. Record each micrometer adjustment reading and the corresponding slit size; Repeat the above steps, make multiple adjustments and measurements, generally no less than 10 sets of data; Adjust the range to cover the required slit size for the test; Organize the recorded data into a table, listing the micrometer readings and the corresponding slit dimensions; Plot a scatter plot with the micrometer advance as the independent variable and the slit size change as the dependent variable. The least squares method was used to perform a linear fit on the scatter plot to obtain the linear regression equation; Perform a significance test on the fitted function to ensure that the function is statistically significant; Finally, a set of data points that were not involved in the fitting were selected, and the slit size was calculated using the fitted function relationship. The result was then compared with the actual measured value. If the error between the calculated value and the measured value was within ±0.005 mm, the function relationship was considered reliable.

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