An experimental platform with switchable flame modes and its operation method

Abstract

This invention discloses an experimental platform with switchable flame modes and its operating method. The experimental platform includes a burner, a flange top, a flange bottom, a cavity located between the flange top and bottom, a back pressure regulator and a pressure relief port located at the upper end of the flange top, a K-type thermocouple and a pressure sensor located on the outer surface of the cavity, and an electric spark igniter located inside the cavity. The burner and the flange bottom are detachably connected via a mounting plate. During experiments, this invention allows for switching flame modes by disassembling and installing different burners, thereby observing the combustion characteristics of different flames. Only one experimental platform is required, saving costs and simplifying operation.

Description

Technical Field

[0001] This invention relates to an experimental platform with switchable flame modes and its operation method. Background Technology

[0002] Laminar flames are relatively stable flames, and the Bunsen burners used in laboratories produce flames that approximate laminar flames, characterized by smooth surfaces and minimal fluctuations. Turbulent flames, on the other hand, differ from laminar flames in their waveform and propagation speed. They are characterized by rapid propagation and constantly fluctuating flame peaks, and are also noisier than laminar combustion. Combustion is common in our daily lives, especially in combustion equipment such as internal combustion engines and boilers. Studying the characteristics of flame combustion helps increase fuel efficiency, reduce energy loss, and improve combustion efficiency, thus reducing harmful emissions and contributing significantly to environmental protection. Furthermore, the proportion of clean energy used globally is increasing annually, making the development and application of various clean energy sources crucial for modern industrial production.

[0003] In actual fuel use, common industrial equipment operates under high temperature and high pressure conditions. The pressure inside the combustion chamber of some internal combustion engines can approach one hundred atmospheres, while the pressure inside the combustion chamber of rockets can reach two hundred atmospheres. Under these conditions, the fuel combustion process is often complex and not a single type of combustion. Existing technologies include experimental platforms for observing the combustion characteristics of flames, but these platforms can only be used to experiment on one type of flame. To study both laminar and turbulent flames, two different experimental platforms are required, which is costly and cumbersome to operate. Summary of the Invention

[0004] To address the technical problem mentioned in the background art of requiring different experimental platforms when studying different flame types, this invention proposes an experimental platform with switchable flame modes and its operation method, as detailed below:

[0005] A test bench with switchable flame modes includes a burner, a flange top, a flange bottom, and a cavity located between the flange top and the flange bottom, a back pressure regulator and a pressure relief port located at the upper end of the flange top, a K-type thermocouple and a pressure sensor located on the outer surface of the cavity, and an electric spark igniter located inside the cavity. The burner and the flange bottom are detachably connected by a mounting plate.

[0006] Preferably, it also includes a sapphire window, a pressure relief valve, and a high-speed camera, the high-speed camera being aimed at the sapphire window.

[0007] Preferably, the burner is a laminar flow burner.

[0008] Preferably, the burner is a turbulent burner, which includes a vortex generator located at the upper end.

[0009] Preferably, the burner includes a feed pipe, and the feed pipe is further equipped with a mass flow meter.

[0010] Preferably, it also includes a frequency converter. The burner includes a rotating cylinder, a driven gear, a turntable, a driving gear, and a motor. The rotating cylinder is rotatably connected to the flange bottom via a mounting plate. The frequency converter can control the speed of the motor. The motor can drive the driving gear to rotate. The driving gear can drive the driven gear to rotate. The driven gear can drive the turntable to rotate. The turntable can drive the rotating cylinder to rotate.

[0011] A method for operating a switchable flame mode experimental platform includes the following steps:

[0012] Step 1: Install the laminar flow burner or turbulent flow burner on the flange base using the mounting plate, depending on the type of flame you want to observe;

[0013] Step 2: Introduce fuel and oxidizer, ignite the flame, and observe the combustion process of the flame using a high-speed camera;

[0014] Step 3: Extinguish the flame and release the gas from the cavity through the pressure relief valve;

[0015] Step 4: Disassemble the burner installed in Step 1, and install another burner on the flange bottom using the mounting plate;

[0016] Step 5: Introduce fuel and oxidizer, ignite the flame, observe the combustion process of the flame through a high-speed camera, extinguish the flame after observation, and exhaust the gas in the cavity through the pressure relief valve.

[0017] A method for operating a switchable flame mode experimental platform includes the following steps:

[0018] Step 1: Install the burner onto the flange base using the mounting plate;

[0019] Step 2: Introduce fuel and oxidizer, ignite the flame, and observe the combustion process of the flame using a high-speed camera;

[0020] Step 3: Control the speed of the motor by controlling the frequency converter, thereby causing the rotating drum to rotate;

[0021] Step 4: Observe the combustion process of the flame using a high-speed camera;

[0022] Step 5: Extinguish the flame and release the gas from the cavity through the pressure relief valve.

[0023] During the experiment, the present invention can switch flame modes by disassembling and installing different burners, thereby observing the technical effects of different flame combustion characteristics. Only one experimental platform is required, which saves costs and is simple to operate. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of an experimental platform with switchable flame modes according to the present invention;

[0025] Figure 2 This is a schematic diagram of the structure of a laminar flow burner in the first embodiment of an experimental platform with switchable flame modes according to the present invention.

[0026] Figure 3 This is a schematic diagram of the turbulent burner of the first embodiment of an experimental platform with switchable flame mode according to the present invention;

[0027] Figure 4 This is a top view of a turbulent burner in the first embodiment of an experimental platform with switchable flame modes according to the present invention;

[0028] Figure 5 This is a schematic diagram of the burner structure of a second embodiment of an experimental platform with switchable flame modes according to the present invention;

[0029] Figure 6 This is a front view of the burner of a second embodiment of an experimental platform with switchable flame modes according to the present invention.

[0030] In the diagram: 1-Back pressure regulator; 2-Pressure relief valve; 3-Flange top; 4-K-type thermocouple; 5-Cavity; 6-Electric spark igniter; 7-High-speed camera; 8-Pressure sensor; 9-Sapphire window; 10-Flange bottom; 11-Burner; 12-Mass flow meter; 13-Mounting plate; 14-Eddy current generator; 15-Turbulent burner; 16-Passive gear; 17-Motor; 18-Turntable; 19-Driving gear; 20-Rotating cylinder; 21-Frequency converter; 22-Laminar flow burner. Detailed Implementation

[0031] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, 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.

[0032] This invention discloses an experimental platform with switchable flame modes, comprising a burner 11, a flange top 3, a flange bottom 10, a cavity 5 located between the flange top 3 and the flange bottom 10, a back pressure regulator 1 and a pressure relief valve 2 located at the upper end of the flange top 3, a K-type thermocouple 4 and a pressure sensor 8 located on the outer surface of the cavity 5, and an electric spark igniter 6 located inside the cavity 5. The invention is characterized in that the burner 11 and the flange bottom 10 are detachably connected by a mounting plate 13.

[0033] The experimental platform can withstand a maximum pressure of 3.5 MPa and is made entirely of 316 stainless steel. Different burners 11 can be replaced on the mounting plate 13 to achieve different flame types. Oxidant and fuel enter the chamber 5 through different pipelines. The set value of the back pressure regulator 1 can be adjusted to control the gas discharge inside the chamber 5, so that the experimental pressure reaches the preset pressure value, and is monitored by the pressure sensor 8. The electric spark igniter 6 used in this experimental platform uses a continuous arc electric spark to generate a high-energy electric spark as the ignition source to ignite the fuel. Its basic principle is high-voltage breakdown followed by low-voltage pulse arc continuation, which can reduce the impact of the energy generated during the ignition process on the flame.

[0034] During the experiment, the present invention can switch flame modes by disassembling and installing different burners 11, thereby observing the technical effects of different flame combustion characteristics. Only one experimental platform is required, which saves costs and is simple to operate.

[0035] For example, in a first embodiment of the present invention, the burner 11 includes a laminar flow burner 22 and a turbulent flow burner 15, wherein the turbulent flow burner 15 includes a vortex generating device 14 located at the upper end.

[0036] For ease of observation, two 85mm diameter sapphire windows 9 are installed on both sides of the wall. These windows 9 can be used to collect information such as the speed of flame combustion. The invention also includes a high-speed camera 7, which is aimed at the sapphire windows 9 to capture images. The high-speed camera 7 used in the experiment can record the flame combustion process at a very high shooting frequency, typically up to one thousand frames per second, and is continuously variable. The invention also includes a pressure relief valve 2; after the flame is extinguished during the experiment, opening the pressure relief valve 2 allows the remaining gas in the cavity 5 to be discharged.

[0037] To observe the combustion characteristics of a laminar flame, simply install the laminar burner 22 on the flange bottom 10 via the mounting plate 13. Then, introduce the oxidant and fuel into the cavity 5, ignite the flame using the electric spark igniter 6, and take a picture of the sapphire window 9 using the high-speed camera 7. The picture can then be analyzed. To observe the combustion characteristics of a turbulent flame, simply extinguish the flame, open the pressure relief valve 2 to release the gas from the cavity 5, remove the laminar burner 22, and install the turbulent burner 15 on the flange bottom 10 via the mounting plate 13. Introduce the oxidant and fuel into the cavity 5. Since the oxidant and fuel pass through the eddy current generator 14 before entering the cavity 5, a turbulent flame will be generated inside the cavity 5 after ignition using the electric spark igniter 6.

[0038] In order to observe the relationship between the combustion characteristics of the flame and the ratio of oxidant to fuel, preferably, the burner 11 also includes a feed pipe, on which a mass flow meter 12 is provided, and the mass of fuel entering the chamber 5 can be controlled by controlling the mass flow meter 12.

[0039] In a second embodiment of the present invention, an experimental platform with switchable flame modes further includes a frequency converter 21. The burner 11 includes a rotating cylinder 20, a driven gear 16, a turntable 18, a driving gear 19, and a motor 17. The rotating cylinder 20 is rotatably connected to the flange bottom 10 via a mounting plate 13. The frequency converter 21 can control the rotation speed of the motor 17. The motor 17 can drive the driving gear 19 to rotate. The driving gear 19 can drive the driven gear 16 to rotate. The driven gear 16 can drive the turntable 18 to rotate. The turntable 18 can drive the rotating cylinder 20 to rotate.

[0040] It should be noted that if the radius of the rotating cylinder 20 is R, the number of teeth of the driving gear 19 is n1, the number of teeth of the driven gear 16 is n2, and the speed of the motor 17 is r1 (in rpm), then the speed of the rotating cylinder 20 is r2 = (n1 / n2)r1, and the tangential velocity of the rotating cylinder 20 is v = πRr2 / 30. Since the rotation of the rotating cylinder 20 exerts a tangential frictional force on the surrounding gas, causing the surrounding gas to form a vortex around its center, and the greater the tangential velocity of the rotating cylinder, the stronger the vortex formed. Therefore, by controlling the frequency converter 21 to send an electrical signal, thereby controlling the speed of the motor 17, the combustion characteristics of the flame inside the cavity 5 can be controlled.

[0041] In operation, to observe the combustion characteristics of a laminar flame, simply stop the motor 17 from rotating, then introduce fuel and oxidant to ignite the flame. The high-speed camera 7 then captures an image of the sapphire window 9, which can then be analyzed. To observe the combustion characteristics of a turbulent flame, it is not necessary to extinguish the flame. Simply control the rotation speed of the motor 17 via the frequency converter 21. Once stable, the high-speed camera 7 captures an image of the sapphire window 9, which can then be analyzed. Alternatively, the flame can be extinguished, the rotation speed of the motor 17 adjusted, and the flame re-ignited after stabilization. In this embodiment, the combustion characteristics of different turbulent flames can also be observed by changing the rotation speed of the motor 17.

[0042] An operating method for an experimental platform with switchable flame modes according to Embodiment 1, characterized by comprising the following steps:

[0043] Step 1: Install the laminar flow burner 22 or turbulent flow burner 15 onto the flange base 10 via the mounting plate 13, depending on the type of flame you want to observe;

[0044] Step 2: Introduce fuel and oxidizer, ignite the flame, and observe the combustion process of the flame through high-speed camera 7;

[0045] Step 3: Extinguish the flame and release the gas from the cavity 5 through the pressure relief valve 2;

[0046] Step 4: Disassemble the burner installed in Step 1, and install another burner on the flange bottom 10 via the mounting plate 13;

[0047] Step 5: Introduce fuel and oxidizer, ignite the flame, observe the combustion process of the flame through the high-speed camera 7, extinguish the flame after observation, and exhaust the gas in the cavity 5 through the pressure relief valve 2.

[0048] An operating method for an experimental platform with switchable flame modes according to Embodiment 2, characterized by comprising the following steps:

[0049] Step 1: Install the burner 11 onto the flange base 10 via the mounting plate 13;

[0050] Step 2: Introduce fuel and oxidizer, ignite the flame, and observe the combustion process of the flame through high-speed camera 7;

[0051] Step 3: Control the speed of the motor 17 by controlling the frequency converter 21, thereby causing the rotating drum 20 to rotate;

[0052] Step 4: After stabilization, observe the combustion process of the flame using high-speed camera 7;

[0053] Step 5: Extinguish the flame and release the gas from the cavity 5 through the pressure relief valve 2.

[0054] Furthermore, any content not described in detail in this specification is existing technology known to those skilled in the art.

[0055] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0056] 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 test bench with switchable flame modes, comprising a burner, a flange top, a flange bottom, and a cavity located between the flange top and flange bottom, a back pressure regulator and a pressure relief port located at the upper end of the flange top, a K-type thermocouple and a pressure sensor located on the outer surface of the cavity, and an electric spark igniter located inside the cavity, characterized in that, The burner and the flange base are detachably connected via a mounting plate; It also includes a frequency converter. The burner includes a rotating cylinder, a driven gear, a turntable, a driving gear, and a motor. The rotating cylinder is rotatably connected to the flange bottom via a mounting plate. The frequency converter can control the speed of the motor. The motor can drive the driving gear to rotate. The driving gear can drive the driven gear to rotate. The driven gear can drive the turntable to rotate. The turntable can drive the rotating cylinder to rotate. The rotation of the rotating cylinder will apply tangential friction to the surrounding gas, thereby causing the surrounding gas to form a vortex around the center of the rotating cylinder.

2. The experimental platform with switchable flame mode as described in claim 1, characterized in that, It also includes a sapphire window, a pressure relief valve, and a high-speed camera, the high-speed camera being aimed at the sapphire window.

3. The experimental platform with switchable flame mode as described in claim 2, characterized in that, The burner is a laminar flow burner.

4. The experimental platform with switchable flame mode as described in claim 2, characterized in that, The burner is a turbulent burner, which includes a vortex generator located at the upper end.

5. An experimental platform with switchable flame modes as described in claim 3 or 4, characterized in that, The burner includes a feed pipe, and a mass flow meter is also installed on the feed pipe.

6. A method for operating a switchable flame mode experimental platform, employing the switchable flame mode experimental platform as described in any one of claims 1 to 5, characterized in that, Includes the following steps: Step 1: Install the burner onto the flange base using the mounting plate; Step 2: Observe the combustion characteristics of the laminar flame. Keep the motor off, introduce fuel and oxidant to ignite the flame, observe the combustion process of the flame through a high-speed camera, and then analyze the photos. Step 3: Observe the combustion characteristics of the turbulent flame. Control the speed of the motor by controlling the frequency converter, so that the rotating drum rotates. The rotation of the rotating drum will apply tangential friction to the surrounding gas, so that the surrounding gas forms a vortex around the center of the rotating drum. After stabilization, take a picture of the sapphire window with a high-speed camera, and then analyze the picture. By changing the rotation speed of the motor, the combustion characteristics of different turbulent flames were observed when the motor speed was different; the combustion process of the flame was observed using a high-speed camera. Step 4: Extinguish the flame and release the gas from the cavity through the pressure relief valve.

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