A double-path annular distributed uniform gas mixing device and method suitable for air flow mixing

Abstract

The application belongs to the technical field of supersonic flame gun gas regulation, and particularly relates to a double-path annular distributed uniform gas mixing device and method suitable for airflow mixing, which comprises an annular body, a central through hole is formed in the middle of the annular body along the axial direction, and an internal thread is arranged on the inner wall of the central through hole; a first annular gas storage cavity and a second annular gas storage cavity are coaxially arranged in the interior of the annular body, a plurality of gas injection holes are arranged on the front surface of the annular body and are uniformly distributed in the circumferential direction, the gas injection holes comprise first inclined gas injection holes and second inclined gas injection holes which are arranged at intervals, the first inclined gas injection holes are communicated with the first annular gas storage cavity, and the second inclined gas injection holes are communicated with the second annular gas storage cavity; a first gas outlet and a second gas outlet are arranged on the rear surface of the annular body, the first gas outlet is communicated with the first annular gas storage cavity, and the second gas outlet is communicated with the second annular gas storage cavity; and the technical problem that the existing annular gas distribution regulation device cannot independently inject gas in different zones due to single internal cavity gas supply is solved.

Description

Technical Field

[0001] This invention relates to the field of gas control technology for high-velocity vapor deposition (HVOF / HVAF) spray guns, specifically to a dual-path annular distributed uniform gas mixing device and method suitable for mixing the flame and gas flow of a high-velocity vapor deposition (HVOF) spray gun. Background Technology

[0002] During supersonic flame spraying, multiple functional gases, such as those for combustion enhancement, oxygen suppression and dilution, and cooling protection, need to be introduced into the flame stream simultaneously to regulate the flame stream's temperature field, velocity field, and oxygen content, thereby ensuring coating quality.

[0003] Existing spray gun annular gas distribution devices mostly adopt a single gas storage chamber structure, where all injection holes can only inject the same gas. This makes it impossible to achieve independent adjustment and zoned supply of multiple gases, resulting in low precision in flame composition control and difficulty in balancing powder melting efficiency and anti-oxidation requirements. Some solutions use axially layered arrangement of multiple single-chamber gas distribution rings to achieve multi-path gas supply, but this method significantly increases the axial length of the spray gun, reduces the accessibility of deep hole spraying, and the injection of different gases at different cross sections leads to uneven circumferential distribution, which can easily cause flame deflection and combustion oscillation. The multi-layer structure also has many assembly interfaces, resulting in poor sealing reliability under high temperature and high pressure.

[0004] In summary, existing supersonic spray gun gas distribution devices have significant technical shortcomings in the simultaneous input of multiple gases: the single-cavity structure cannot achieve independent and precise control of multiple gases; the axial layering scheme leads to an increased spray gun size and uneven circumferential distribution; and an unreasonable gas injection method interferes with the stability of the main flame. Developing a ring-shaped gas distribution device that can achieve independent input of multiple gases within the same axial cross-section, uniformly alternating circumferential distribution, and minimal interference with the main flame is an urgent technical requirement for improving the quality and process flexibility of supersonic flame spraying. Summary of the Invention

[0005] To address the technical problems of existing supersonic spray gun gas distribution devices, such as the inability to achieve independent and precise control of multiple gases due to the use of a single gas storage chamber, the increase in spray gun size and uneven circumferential distribution due to axial layered multi-ring schemes, and the interference of unreasonable gas injection methods with the stability of the main flame, this invention provides a dual-path annular distributed uniform gas mixing device and method suitable for gas mixing.

[0006] This invention is achieved using the following technical solution: A dual-path annular distributed uniform gas mixing device suitable for gas mixing includes an annular body, wherein a central through hole is provided in the middle of the annular body along the axial direction, and the inner wall of the central through hole is provided with internal threads. The annular body has a first annular air storage cavity and a second annular air storage cavity coaxially formed inside. The front surface of the annular body has a plurality of air injection holes evenly distributed along the circumference. The air injection holes include a first oblique air injection hole and a second oblique air injection hole arranged at intervals. The first oblique air injection hole is connected to the first annular air storage cavity, and the second oblique air injection hole is connected to the second annular air storage cavity. The rear surface of the annular body is provided with a first air inlet and a second air inlet. The first air inlet is connected to the first annular air storage cavity, and the second air inlet is connected to the second annular air storage cavity.

[0007] Furthermore, the internal thread is a cylindrical pipe thread or a tapered sealing thread.

[0008] Furthermore, the annular body is an integral annular structure, and the internal thread of the inner wall of its central through hole is integrally formed with the annular body.

[0009] Furthermore, the first and second oblique air injection holes are respectively set at an angle of 30° relative to the central axis of the annular body.

[0010] Furthermore, both the outer walls of the first and second air inlets are provided with external threads.

[0011] Furthermore, the first annular gas storage cavity is located radially inside the second annular gas storage cavity, near the central through hole.

[0012] Furthermore, the external thread is a cylindrical pipe thread or a tapered sealing thread.

[0013] A dual-path annular distributed uniform gas mixing method suitable for airflow mixing, employing the dual-path annular distributed uniform gas mixing device described in this invention, includes the following steps: First, the device is threadedly assembled with the combustion chamber of the supersonic flame gun, the injection assembly, or the external pipeline components through the internal thread on the inner wall of the central through hole of the annular body, thereby achieving axial positioning, coaxial calibration, and sealing fixation of the device. Then, the first gas enters the first annular gas storage chamber through the first gas inlet, and the second gas enters the second annular gas storage chamber through the second gas inlet; Finally, the first gas in the first annular gas storage chamber is ejected obliquely through each of the first oblique injection holes connected to it, and the second gas in the second annular gas storage chamber is ejected obliquely through each of the second oblique injection holes connected to it. The two gases are mixed at the combustion chamber outlet.

[0014] This invention provides a dual-path annular distributed uniform gas mixing device and method suitable for gas flow mixing, which has the following advantages compared with the prior art: 1. This invention, by setting up a first annular gas storage chamber and a second annular gas storage chamber that are independent and not interconnected, and by adopting an alternating perforation method in which the first oblique gas injection hole is connected to the first annular gas storage chamber and the second oblique gas injection hole is connected to the second annular gas storage chamber, achieves zoned independent gas supply and circumferential alternating injection of two different control media within the same axial cross section. The flow rate and composition of each gas can be independently adjusted according to the combustion state, which significantly improves the adjustment accuracy of the oxygen content of the fuel gas and the afterburning ratio, and solves the technical defect of the existing single internal cavity structure that cannot be zoned independently for gas injection.

[0015] 2. By setting an internal thread of cylindrical pipe thread or conical sealing thread on the inner wall of the central through hole, the present invention enables thread engagement, coaxial positioning and sealing assembly between the device and the combustion chamber of the supersonic flame spray gun and the injection assembly. This significantly improves the coaxiality of the assembly and the sealing reliability under high temperature and high pressure conditions, effectively avoids problems such as air leakage, loose assembly and structural deformation, and ensures the long-term stable operation of the device under extreme conditions.

[0016] 3. In this invention, all the oblique injection holes are arranged on the same axial section of the annular body, which avoids the problem of increased axial size of the device caused by the axial gas distribution method. The structure is more compact and saves space inside the combustion chamber. At the same time, the first and second oblique injection holes are arranged alternately in the circumferential direction in the same section, so that the two gas streams form a uniformly spaced staggered jet coverage in the circumferential direction. This avoids the problem of uneven local afterburning and flame deflection caused by the axial gas distribution, which is conducive to the symmetrical stability and organization optimization of the combustion flame.

[0017] 4. The present invention adopts an integrated ring structure, with the internal thread and the ring body integrally machined, eliminating the need for additional assembly connectors, reducing connection interfaces and potential leakage points, and ensuring good overall structural integrity.

[0018] 5. In this invention, the first and second oblique gas injection holes are both arranged at a 30° angle toward the central axis of the annular body, so that the injected gas flows into the core area of ​​the flame in an oblique jet manner, which reduces the impact and interference on the main combustion flow field, optimizes the flame flow field structure, and helps to stabilize the flame shape. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0020] Figure 2 This is a partial structural schematic diagram of the present invention.

[0021] In the figure: 1. Internal thread; 2. First annular air storage chamber; 3. Second annular air storage chamber; 4. First oblique air injection hole; 5. Second oblique air injection hole; 6. First air outlet; 7. Second air outlet. Detailed Implementation

[0022] The present invention will be further explained and described below with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are only some embodiments, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] like Figure 1 and Figure 2 As shown, this embodiment provides a dual-path annular distributed uniform gas mixing device and method suitable for gas flow mixing, mainly used for gas component control, secondary combustion, and oxygen suppression in supersonic flame torches. The device includes an annular body, integrally formed from a high-temperature resistant alloy material, with an overall axisymmetric annular structure. This structure can adapt to the extreme working environment of high temperature and high pressure in supersonic flame torches, effectively resisting thermal stress and high-pressure gas flow impact, and preventing structural deformation failure.

[0024] The annular body has a central through hole along the axial direction in the middle, and the inner wall of the central through hole is provided with an internal thread 1, which is a cylindrical pipe thread or a conical sealing thread. The internal thread 1 is used to achieve thread engagement, coaxial positioning and sealing assembly with the supersonic flame torch combustion chamber, injection assembly or external pipeline components, to ensure high coaxiality and reliable sealing between the device and other components, and to avoid air leakage or loosening of assembly under high temperature and high pressure conditions.

[0025] The annular body is an integral annular structure. The internal thread 1 of the inner wall of its central through hole is integrally machined with the annular body, eliminating the need for additional threaded sleeves or connectors. This reduces the connection interface and potential leakage points, further improving the overall structure and high-temperature sealing reliability.

[0026] The annular body has a first annular gas storage chamber 2 and a second annular gas storage chamber 3 coaxially arranged inside. The first annular gas storage chamber 2 is located radially inner to the second annular gas storage chamber 3, closer to the central through hole, while the second annular gas storage chamber 3 is located radially outer to the second annular gas storage chamber 3, farther from the central through hole. Both the first annular gas storage chamber 2 and the second annular gas storage chamber 3 are annular cavities, independent of each other and not connected, separated by the solid structure of the annular body, forming two independent sealed gas paths. This dual-cavity independent layout completely isolates the two gas media inside the device, preventing different gases from mixing or cross-contaminating before entering the combustion zone, providing a structural basis for subsequent zoned differentiated injection.

[0027] The front surface of the annular body has several injection holes evenly distributed circumferentially. These injection holes include a first oblique injection hole 4 and a second oblique injection hole 5 arranged alternately along the circumference. The first oblique injection hole 4 is connected to the first annular gas storage chamber 2, and the second oblique injection hole 5 is connected to the second annular gas storage chamber 3. Through this alternating arrangement and connection to different gas storage chambers, two streams of gas can be alternately ejected circumferentially within the same axial cross-section, forming a uniformly spaced and staggered jet coverage in the circumferential direction. This avoids the problems of uneven local combustion and flame deflection caused by axially spaced gas distribution methods.

[0028] The first oblique injection port 4 and the second oblique injection port 5 are respectively set at an angle of 30° relative to the central axis of the annular body, and the outlet end of each oblique injection port faces the central axis of the annular body. This 30° oblique arrangement allows the gas ejected from the front surface of the annular body to converge in an oblique jet manner in the flame core area near the central axis, reducing the direct impact of the jet on the flame and forming a streamlined airflow convergence effect, which helps to optimize the flow field structure and stabilize the flame morphology.

[0029] The rear surface of the annular body is provided with a first air inlet 6 and a second air inlet 7. The first air inlet 6 is connected to the first annular air storage cavity 2, and the second air inlet 7 is connected to the second annular air storage cavity 3. The outer walls of the first air inlet 6 and the second air inlet 7 are provided with external threads, and the external threads are cylindrical pipe threads or conical sealing threads, which are used to engage and seal with the threads of external air supply pipelines to ensure that the two external air sources enter the corresponding air storage cavities independently and in a sealed manner.

[0030] The device operates as follows: First, the entire device is threadedly assembled with the supersonic flame torch combustion chamber, injection assembly, or external pipeline components via the internal thread 1 on the inner wall of the central through hole of the annular body, achieving axial positioning, coaxial alignment, and sealing fixation of the device. The internal thread 1 adopts a cylindrical pipe thread or a tapered sealing thread to ensure good connection strength and sealing performance under high temperature and high pressure conditions after assembly.

[0031] Secondly, two external gas sources enter the device through the first gas inlet 6 and the second gas inlet 7, respectively. The first gas enters the first annular gas storage chamber 2 through the first gas inlet 6, and the second gas enters the second annular gas storage chamber 3 through the second gas inlet 7. The two gas sources complete pressure stabilization and airflow distribution within their respective independent annular gas storage chambers, ensuring that the gas is evenly distributed circumferentially in the corresponding annular gas storage chambers, providing a gas source with uniform pressure and stable flow for subsequent gas injection holes.

[0032] Then, the first stream of gas in the first annular gas storage chamber 2 is ejected obliquely through the first oblique injection holes 4 connected to it, entering the flame combustion zone; the second stream of gas in the second annular gas storage chamber 3 is ejected obliquely through the second oblique injection holes 5 connected to it, entering the flame combustion zone. Both streams of gas are guided at a 30° angle and are ejected obliquely towards the flame core area near the central axis, forming a zoned, directional, circumferential alternating jet coverage.

[0033] Finally, the two streams of gases with different components or functions each play their respective roles in the flame combustion zone. One stream of gas can be used for secondary combustion matching, supplementing the oxidizer or fuel components required for combustion; the other stream of gas can be used for local oxygen suppression and dilution, reducing the local flame temperature or adjusting the oxygen content of the fuel gas. The two streams of gas work together to achieve precise fuel gas composition adjustment, enhanced secondary combustion, and stable flame control.

[0034] Throughout the entire operation, the first annular gas storage chamber 2 and the second annular gas storage chamber 3 are independent and not connected to each other, ensuring complete isolation of the two gas media within the device and preventing cross-contamination or mixing, thus guaranteeing the accuracy and reliability of the zoned gas supply. Simultaneously, since all the angled injection holes are arranged at a 30° angle towards the central axis, the injected gas flows into the flame area in a streamlined manner, reducing interference with the main combustion flow field, avoiding flame deflection and combustion oscillation, and ensuring combustion stability.

[0035] In the description of this invention, it should be understood that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0036] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A dual-path annular distributed uniform gas mixing device suitable for gas flow mixing, comprising an annular body, characterized in that: The annular body has a central through hole along the axial direction in the middle part, and the inner wall of the central through hole is provided with an internal thread (1). The annular body has a first annular gas storage cavity (2) and a second annular gas storage cavity (3) coaxially formed inside. The front surface of the annular body has a number of gas injection holes evenly distributed along the circumference. The gas injection holes include a first oblique gas injection hole (4) and a second oblique gas injection hole (5) arranged at intervals. The first oblique gas injection hole (4) is connected to the first annular gas storage cavity (2), and the second oblique gas injection hole (5) is connected to the second annular gas storage cavity (3). The rear surface of the annular body is provided with a first air inlet (6) and a second air inlet (7). The first air inlet (6) is connected to the first annular air storage cavity (2), and the second air inlet (7) is connected to the second annular air storage cavity (3).

2. The dual-path annular distributed uniform gas mixing device suitable for gas flow mixing according to claim 1, characterized in that, The internal thread (1) is a cylindrical pipe thread or a tapered sealing thread.

3. A dual-path annular distributed uniform gas mixing device suitable for gas flow mixing according to claim 1, characterized in that, The annular body is an integral annular structure, and the internal thread (1) on the inner wall of its central through hole is integrally formed with the annular body.

4. A dual-path annular distributed uniform gas mixing device suitable for gas flow mixing according to claim 1, characterized in that, The first oblique air injection hole (4) and the second oblique air injection hole (5) are respectively set at an angle of 30° relative to the central axis of the annular body.

5. A dual-path annular distributed uniform gas mixing device suitable for gas flow mixing according to claim 1, characterized in that, The outer walls of the first air inlet (6) and the second air inlet (7) are both provided with external threads.

6. A dual-path annular distributed uniform gas mixing device suitable for gas flow mixing according to claim 1, characterized in that, The first annular gas storage chamber (2) is located radially inside the second annular gas storage chamber (3) near the central through hole.

7. A dual-path annular distributed uniform gas mixing device suitable for gas flow mixing according to claim 5, characterized in that, The external thread is a cylindrical pipe thread or a tapered sealing thread.

8. A dual-path annular distributed uniform gas mixing method suitable for gas flow mixing, characterized in that, The dual-path annular distributed uniform gas mixing device as described in claim 1 includes the following steps: First, the device is threadedly assembled with the supersonic flame gun combustion chamber, injection assembly or external pipeline components through the internal thread (1) on the inner wall of the central through hole of the annular body, so as to realize the axial positioning, coaxial calibration and sealing fixation of the device. Then, the first gas enters the first annular gas storage chamber (2) through the first gas inlet (6), and the second gas enters the second annular gas storage chamber (3) through the second gas inlet (7). Finally, the first gas in the first annular gas storage chamber (2) is ejected obliquely through the first oblique injection holes (4) connected to it, and the second gas in the second annular gas storage chamber (3) is ejected obliquely through the second oblique injection holes (5) connected to it. The two gases are mixed at the combustion chamber outlet.

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