A flame propagation characteristic test device

Abstract

This application discloses a flame propagation characteristic testing device, which includes a combustion chamber and a buffer chamber. The combustion chamber includes a transparent enclosure and a first supporting component. The internal space of the transparent enclosure forms a combustion cavity. The transparent enclosure is connected to the first supporting component, which is provided with a microchannel that connects to the internal space of the transparent enclosure. The buffer chamber is provided with a nozzle facing the microchannel, which is used to deliver the combustion-supporting gas mixture to the microchannel. The combustion cavity is defined by the transparent enclosure within the combustion chamber, and the flame formed by the combustion phenomenon is located within the combustion cavity, which is convenient for personnel to observe through the transparent enclosure and also facilitates the optical path of the optical diagnostic system to pass through the combustion cavity. The nozzle delivers the combustion-supporting gas mixture to the microchannel, enabling the flame propagation characteristic testing device to be used to study the quenching mechanism and influencing factors of premixed flames within the microchannel.

Description

Technical Field

[0001] This application relates to the field of experimental equipment, and in particular to a flame propagation characteristic testing device. Background Technology

[0002] As an advanced internal combustion engine technology, pre-combustion chamber technology can significantly improve the thermal efficiency and combustion stability of internal combustion engines by optimizing the ignition and combustion process. In the active pre-combustion chamber, the fuel is ignited by the spark plug and then forms a high-temperature, free radical-rich jet through the nozzle, which in turn ignites the lean mixture in the main combustion chamber.

[0003] Pre-combustion chamber jet ignition can improve ignition energy, extend the lean burn limit, and reduce carbon emissions. However, pre-combustion chamber technology still faces some challenges in practical applications. For example, the premixed flame in the pre-combustion chamber is prone to quenching during its entry into the main combustion chamber through a microchannel, leading to ignition failure or incomplete combustion.

[0004] Currently, test benches such as constant-volume combustion bombs and optical engines, used for visualization experiments of in-cylinder combustion, can simulate part of the combustion process of internal combustion engines, but they cannot directly observe the combustion, propagation, and quenching processes of the premixed flame in the pre-combustion chamber and nozzle. This makes it difficult to study the quenching mechanism and influencing factors of the premixed flame in the microchannel of the pre-combustion chamber, limiting the ability to precisely control the degree of quenching of the premixed flame and the ignition energy of the pre-combustion chamber jet. Summary of the Invention

[0005] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a flame propagation characteristic testing device, which facilitates the observation of the propagation characteristics of premixed flames through microchannels inside the combustion chamber by personnel.

[0006] According to a first aspect embodiment of the flame propagation characteristics testing apparatus, the flame propagation characteristics testing apparatus includes a combustion chamber and a buffer chamber. The combustion chamber includes a transparent enclosure and a first support member. The internal space of the transparent enclosure is used to form a combustion chamber. The transparent enclosure is connected to the first support member. The first support member is provided with a microchannel, which communicates with the internal space of the transparent enclosure. The buffer chamber is provided with a nozzle facing the microchannel, which is used to deliver a combustion-supporting gas mixture to the microchannel.

[0007] The flame propagation characteristic testing device according to the embodiments of this application has at least the following beneficial effects: the combustion chamber is defined by a transparent enclosure, and the flame formed by the combustion phenomenon is located in the combustion chamber, which is convenient for the staff to observe through the transparent enclosure, and also convenient for the optical path of the optical diagnostic system to pass through the combustion chamber, that is, to enter from one side and exit from the other side and be captured by the camera; the nozzle delivers the combustion-supporting gas mixture to the microchannel, so that the flame propagation characteristic testing device can be used to study the quenching mechanism and influencing factors of premixed flame in the microchannel.

[0008] According to some embodiments of this application, the transparent enclosure is made of quartz glass.

[0009] According to some embodiments of this application, the combustion chamber further includes a second support member, the transparent enclosure is provided with an opening, and the first support member and the second support member clamp the transparent enclosure to block the opening.

[0010] According to some embodiments of this application, both the first support member and the second support member are provided with a sealing structure, and the transparent enclosure is sealed to the first support member and the second support member through the sealing structure.

[0011] According to some embodiments of this application, the sealing structure includes a mounting groove and a sealing member disposed in the first support member and the second support member, the sealing member being located inside the mounting groove, and the end of the transparent enclosure being embedded in the mounting groove to abut against the sealing member.

[0012] According to some embodiments of this application, the second support member is provided with a combustion assembly extending into the combustion chamber. The combustion assembly includes an ignition component and a fuel supply component. The fuel supply component is used to supply fuel into the combustion chamber, and the ignition component is used to ignite the fuel in the combustion chamber.

[0013] According to some embodiments of this application, the second support member is connected to a pressure block, which is used to press the fuel supply member against the second support member so that the fuel supply member is connected to the second support member.

[0014] According to some embodiments of this application, the flame propagation characteristics testing device further includes a housing assembly, which includes a support and an isolation component. The combustion chamber and the buffer chamber are both connected to the support, and the support and the isolation component form a hollow space to accommodate the combustion chamber and the buffer chamber.

[0015] According to some embodiments of this application, the buffer chamber is provided with a buffer cavity inside, the buffer cavity is connected to the nozzle, and the outer wall of the buffer chamber is provided with a fuel inlet and an oxidant inlet that communicate with the buffer cavity. The fuel inlet and the oxidant inlet are used to supply fuel and oxidant to the buffer cavity.

[0016] According to some embodiments of this application, the buffer chamber and the housing assembly form a receiving chamber for accommodating the combustion chamber, the buffer chamber being provided with a protective gas inlet, the protective gas inlet communicating with the receiving chamber for supplying protective gas to the receiving chamber.

[0017] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0018] The accompanying drawings are used to provide a further understanding of the technical solutions disclosed in this application and form part of the specification. They are used together with the embodiments disclosed in this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions disclosed in this application.

[0019] Figure 1 This is a schematic diagram of the structure of the flame propagation characteristics testing device according to an embodiment of this application;

[0020] Figure 2 This is a top view of the flame propagation characteristics testing apparatus according to an embodiment of this application;

[0021] Figure 3 This is an exploded view of the combustion chamber in the flame propagation characteristics testing apparatus of this application embodiment;

[0022] Figure 4 This is a right view of the combustion chamber in the flame propagation characteristics testing apparatus of this application embodiment;

[0023] Figure 5 This is a cross-sectional view of the combustion chamber in the flame propagation characteristics testing apparatus of this application embodiment;

[0024] Figure 6 This is a cross-sectional view of the combustion chamber and buffer chamber in the flame propagation characteristics test apparatus of this application embodiment.

[0025] Figure label:

[0026] Combustion chamber 100; transparent enclosure 101; first support component 102; combustion cavity 103; microchannel 104; second support component 105;

[0027] Ignition component 201; Fuel supply component 202; Compactor 203;

[0028] 301; 302; 303;

[0029] Buffer chamber 400; Nozzle 401; Buffer cavity 402; Fuel inlet 403; Oxidant inlet 404; Protective gas inlet 405. Detailed Implementation

[0030] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0031] In the description of this application, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and 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 this application.

[0032] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0033] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0034] In the description of this application, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0035] like Figure 1 and Figure 2As shown in the figure, this application provides a flame propagation characteristic testing device, which includes a combustion chamber 100 and a buffer chamber 400. Combustion occurs within the combustion chamber 100, allowing personnel to observe the combustion, propagation, and quenching processes within the combustion chamber 100. Simultaneously, the combustion chamber 100 is equipped with microchannels 104, and the buffer chamber 400 injects a combustion-supporting gas mixture along the microchannels 104 into the combustion chamber 100, facilitating the study of the quenching mechanism and influencing factors of the premixed flame within the microchannels.

[0036] In some examples, the combustion chamber 100 includes a transparent enclosure 101, which is entirely made of a transparent material, and the hollow portion of the transparent enclosure 101 forms a combustion cavity 103. Combustion occurs within the combustion cavity 103, meaning the flame generated by combustion is located within the combustion cavity 103.

[0037] Because all parts of the transparent enclosure 101 are transparent, it is convenient for staff to observe the combustion phenomenon inside the combustion chamber 103 from various angles and positions. In addition, the combustion chamber 103 is also suitable for optical diagnostic systems. Optical diagnostic systems involve emission and capture processes. Since the transparent enclosure 101 is transparent in all directions, light can enter from one side of the transparent enclosure 101 and exit from the other side and be captured by a camera, making it highly versatile.

[0038] Furthermore, the transparent enclosure 101 is generally formed into a cylindrical structure. The shape of the cylindrical structure is set according to actual needs. Specifically, there are openings at both ends of the transparent enclosure 101.

[0039] At the same time, such as Figure 3 , Figure 4 and Figure 5 As shown, the combustion chamber 100 also includes a first support member 102, which is formed as a plate structure, and a transparent enclosure 101 is connected to the first support member 102. Specifically, the first support member 102 covers one end opening of the transparent enclosure 101, and the first support member 102 and the transparent enclosure 101 together define the combustion chamber 103.

[0040] In addition, the microchannel 104 is disposed through the first support component 102, which facilitates the study of the quenching mechanism and influencing factors of the premixed flame within the microchannel. Since the microchannel 104 is located within the opening of the transparent enclosure 101, the microchannel 104 connects to the combustion chamber 103.

[0041] In some examples, the transparent enclosure 101 is made of quartz glass, and the quartz glass can be set at different heights to change the volume of the combustion chamber 103. Various optical diagnostic methods, such as schlieren, planar laser-induced fluorescence, and sample image velocimetry, can be applied to the combustion chamber 103 for high-frequency diagnostics to study the flame propagation process, particle motion, and the distribution of important free radicals.

[0042] In some examples, such as Figure 3 , Figure 4 and Figure 5 As shown, the combustion chamber 100 also includes a second support member 105, which is also formed as a plate structure. The second support member 105 covers the opening at the other end of the transparent enclosure 101, that is, the first support member 102 and the second support member 105 together clamp the transparent enclosure 101, so that the combustion chamber 103 forms a relatively closed space.

[0043] Specifically, the first support member 102 is located at the bottom of the transparent enclosure 101, and the second support member 105 is located at the top of the transparent enclosure 101. The first support member 102 and the second support member 105 are interconnected by a number of fasteners to maintain their clamping effect on the transparent enclosure 101. Since the horizontal dimension of the first support member 102 and the second support member 105 is larger than the horizontal dimension of the transparent enclosure 101, the fasteners are distributed on the outer side of the transparent enclosure 101.

[0044] In some examples, to ensure the airtightness between the transparent enclosure 101 and the first support member 102, and between the transparent enclosure 101 and the second support member 105, both the first support member 102 and the second support member 105 are provided with sealing structures. One open end of the transparent enclosure 101 is connected to the first support member 102 through a sealing structure, and the other open end is connected to the second support member 105 through a sealing structure, thereby ensuring the airtightness between the transparent enclosure 101, the first support member 102, and the second support member 105.

[0045] In some examples, the sealing structure includes mounting grooves and sealing components disposed in the first support member 102 and the second support member 105. Specifically, the shape of the mounting groove matches the shape of the end opening of the transparent enclosure 101, and the sealing component is a sealing ring.

[0046] The sealing ring is installed inside the mounting groove, and the end of the transparent enclosure 101 is embedded in the mounting groove to ensure the installation accuracy of the transparent enclosure 101. The transparent enclosure 101 abuts against the sealing component, and the sealing component plays a sealing role between the transparent enclosure 101 and the first support component 102.

[0047] In some examples, the second support member 105 is provided with a combustion assembly extending into the combustion chamber 103, the combustion assembly passing through the second support member 105. The combustion assembly includes an ignition member 201 and a fuel supply member 202. Specifically, the ignition member 201 is a spark plug, the fuel supply member 202 is an injector, and the ignition member 201 is threadedly connected to the second support member 105 and passes obliquely through the second support member 105.

[0048] The fuel supply component 202 is used to supply fuel to the combustion chamber 103, and the ignition component 201 is used to ignite the fuel in the combustion chamber 103.

[0049] Furthermore, the ignition component 201 is equipped with a spark plug-type pressure sensor for precise control of ignition timing. Simultaneously, the pressure sensor can also collect pressure information within the combustion chamber 103. The fuel supply component 202 can change the fuel injection pressure and pulse width, allowing a certain mass of fuel to be injected into the combustion chamber 103 at a preset injection pressure and pulse width, thereby forming a premixed gas of the required equivalence concentration within the combustion chamber 103.

[0050] In some examples, the second support member 105 is connected to a pressure block 203, which is connected to the fuel supply member 202, with the fuel supply member 202 positioned between the second support member 105 and the pressure block 203. The pressure block 203 and the second support member 105 clamp the fuel supply member 202, and the pressure block 203 transmits a preload to the fuel supply member 202, causing the fuel supply member 202 to continuously press against the second support member 105.

[0051] It is understood that the pressure block 203 and the second support component 105 are spaced apart and connected to each other by a number of fasteners. Specifically, the fasteners are distributed on the outside of the fuel supply component 202.

[0052] In addition, to ensure the connection stability and sealing between the fuel supply component 202 and the pressure block 203 and the second support component 105, the fuel supply component 202 and the pressure block 203 are sealed by a sealing ring, and the fuel supply component 202 and the second support component 105 are pressed and sealed by a copper gasket.

[0053] In some examples, such as Figure 1 As shown, the flame propagation characteristic testing device also includes a housing assembly, which comprises a support 301 and an isolation component 302. Several supports 301 are provided, and isolation components 302 connect adjacent supports 301, thus forming a hollow space together. Specifically, the isolation component 302 is made of glass, making the space enclosed by the supports 301 and the isolation component 302 relatively enclosed, and facilitating observation of combustion phenomena by personnel through the isolation component 302.

[0054] Furthermore, the combustion chamber 100 and the buffer chamber 400 are connected to the bracket 301 and are located within the space enclosed by the bracket 301 and the isolation component 302. Simultaneously, each bracket 301 together forms a channel for adjusting the height of the combustion chamber 100. The second support component 105 in the combustion chamber 100 is slidably connected to the bracket 301. When the second support component 105 is adjusted to a preset height, it is securely connected to the bracket 301 by fasteners, thereby locking the height of the combustion chamber 100.

[0055] In some examples, such as Figure 6 As shown, the buffer chamber 400 is formed as a hollow structure, and the buffer chamber 400 is provided with a nozzle 401. The nozzle 401 is connected to the hollow part of the buffer chamber 400 and faces the microchannel 104.

[0056] The buffer chamber 400 is used to contain the combustion-supporting gas mixture. Under the action of the nozzle 401, the combustion-supporting buffer gas is sprayed to the position of the microchannel 104. Since there is a flame inside the combustion chamber 103, and the flame will be ejected from the combustion chamber 103 along the microchannel 104, the ejected flame and the combustion-supporting buffer gas interact outside the microchannel 104. The combustion-supporting gas mixture can be in various forms, such as an oxidant or a mixture of oxidant and fuel, which facilitates the study of phenomena such as quenching of the flame ejected from the microchannel under different incoming gas flows.

[0057] In some examples, the hollow portion inside the buffer chamber 400 is the buffer cavity 402, which is connected to the nozzle 401. The outer wall of the buffer chamber 400 is provided with a fuel inlet 403 and an oxidant inlet 404 that communicate with the buffer cavity 402. The fuel inlet 403 is used to supply fuel into the buffer cavity 402, and the oxidant inlet 404 is used to supply oxidant into the buffer cavity 402, thereby forming a combustion-supporting gas mixture inside the buffer cavity 402.

[0058] The buffer chamber 400 is equipped with a pressure sensor. Gas drawn from the gas cylinder and used to fill the buffer chamber 400, according to Dalton's law of partial pressure, can be a mixture of oxidizer and fuel gas. Understandably, the specific composition of the gas mixture needs to be calculated first, then it is introduced into the buffer chamber 400 and ejected from the nozzle 401, thus forming an incoming gas flow within the combustion chamber 103. By changing the gas composition, the quenching phenomenon of the jet flame and the flame propagation phenomenon of the jet flame igniting the incoming flow can be investigated.

[0059] Specifically, a heating wire is installed around the buffer chamber 400, and a temperature sensor is installed inside. By controlling the temperature of the mixed gas inside the buffer chamber 400 through the heating wire, the influence of the incoming flow temperature on flame propagation can be investigated.

[0060] In some examples, the combustion chamber 100 is located on top of the buffer chamber 400, which, together with the housing assembly, forms a receiving chamber 303 for accommodating the combustion chamber 100. It is understood that the receiving chamber 303 is located on top of the buffer chamber 400.

[0061] Furthermore, the buffer chamber 400 is provided with a protective gas inlet 405, which connects to the receiving chamber 303. The protective gas can fill the receiving chamber 303 along the protective gas inlet 405, providing a certain degree of protection against unexpected situations that may occur during combustion. Specifically, nitrogen is used as the protective gas.

[0062] When conducting tests using a flame propagation characteristic testing device, it is necessary to control a single variable. These single variables include the type of fuel in the quartz glass combustion chamber 100, the diameter and length of the microchannel 104, the equivalence ratio of the mixture in the combustion chamber 103, the volume of the combustion chamber 103, the distance between the microchannel 104 and the incoming flow, the composition of the incoming gas, the velocity of the incoming gas, and the temperature of the incoming gas.

[0063] In summary, in practical implementation, the flame propagation characteristic testing device is beneficial for enhancing optical observation capabilities, refining variable control, and improving functionality and flexibility. Regarding enhanced optical observation capabilities, this application proposes a visualization combustion device that utilizes a highly transparent, heat-resistant quartz glass window to achieve comprehensive direct observation of the premixed flame combustion process. Combined with optical diagnostic technology, detailed information on flame structure, propagation dynamics, and chemical reactions can be obtained. Regarding refined variable control, this application establishes a precision control system, unlike traditional constant-volume combustion systems. It can adjust key parameters such as the incoming flow equivalence ratio, flow velocity, channel length, diameter, and premixed equivalence ratio individually or in combination, systematically exploring the specific impacts of these factors on flame quenching, propagation speed, and combustion efficiency, providing detailed data support for optimizing jet ignition technology. Regarding improved functionality and flexibility, this application adopts a modular design, with tight connections between components that are easy to disassemble and replace. Parameters such as nozzle position, height, and orifice diameter can be quickly adjusted according to specific research objectives without a complex reconfiguration process, improving experimental efficiency and flexibility, and making it suitable for combustion research under various fuels and operating conditions.

[0064] In some alternative embodiments, the functions / operations mentioned in the block diagrams may not occur in the order shown in the operation diagrams. For example, depending on the functions / operations involved, two consecutively shown blocks may actually be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order. Furthermore, the embodiments presented and described in the flowcharts of this application are provided by way of example to provide a more comprehensive understanding of the technology. The disclosed methods are not limited to the operations and logic flows presented herein. Alternative embodiments are contemplated in which the order of various operations is changed and sub-operations described as part of a larger operation are executed independently.

[0065] The embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this application. Furthermore, unless otherwise specified, the embodiments and features described in the embodiments of this application can be combined with each other.

Claims

1. A flame propagation characteristic testing device, characterized in that, include: A combustion chamber includes a transparent enclosure and a first support member. The internal space of the transparent enclosure forms a combustion chamber. The transparent enclosure is connected to the first support member, which has a microchannel communicating with the internal space of the transparent enclosure. Flames are ejected from the combustion chamber along the microchannel. The combustion chamber also includes a second support member. The transparent enclosure has an opening. The first and second support members clamp the transparent enclosure to seal the opening. Both the first and second support members have sealing structures. The transparent enclosure is sealed to the first and second support members through the sealing structures. The sealing structure includes a mounting groove and a sealing member disposed in the first and second support members. The sealing member is located inside the mounting groove, and the end of the transparent enclosure is embedded in the mounting groove to abut against the sealing member. A buffer chamber, wherein the buffer chamber is provided with a nozzle facing the microchannel, the nozzle being used to deliver the combustion-supporting gas mixture to the microchannel; The combustion chamber is defined by the transparent enclosure, and the flame formed by the combustion phenomenon is located within the combustion chamber, allowing the optical path of the optical diagnostic system to pass through the combustion chamber. The optical path of the optical diagnostic system enters from one side of the combustion chamber and exits from the other side, and is captured by a camera. The nozzle delivers the combustion-supporting gas mixture to the microchannel, enabling the flame propagation characteristic test device to be used to study the quenching mechanism and influencing factors of the premixed flame within the microchannel.

2. The flame propagation characteristic testing apparatus according to claim 1, characterized in that, The transparent enclosure is made of quartz glass.

3. The flame propagation characteristic testing apparatus according to claim 1, characterized in that, The second support component is provided with a combustion assembly extending into the combustion chamber. The combustion assembly includes an ignition component and a fuel supply component. The fuel supply component is used to supply fuel into the combustion chamber, and the ignition component is used to ignite the fuel in the combustion chamber.

4. The flame propagation characteristic testing apparatus according to claim 3, characterized in that, The second support member is connected to a pressure block, which is used to press the fuel supply member against the second support member so that the fuel supply member is connected to the second support member.

5. The flame propagation characteristic testing apparatus according to claim 1, characterized in that, The flame propagation characteristics testing device also includes a housing assembly, which includes a support and an isolation component. The combustion chamber and the buffer chamber are both connected to the support. The support and the isolation component form a hollow space to accommodate the combustion chamber and the buffer chamber.

6. The flame propagation characteristic testing apparatus according to claim 1, characterized in that, The buffer chamber has a buffer cavity inside, which is connected to the nozzle. The outer wall of the buffer chamber has a fuel inlet and an oxidant inlet that are connected to the buffer cavity. The fuel inlet and the oxidant inlet are used to supply fuel and oxidant to the buffer cavity.

7. The flame propagation characteristic testing apparatus according to claim 5, characterized in that, The buffer chamber and the housing assembly form a accommodating chamber for accommodating the combustion chamber. The buffer chamber is provided with a protective gas inlet, which is connected to the accommodating chamber for supplying protective gas to the accommodating chamber.

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