Rijke tube experimental device with variable heating resistance wire

Abstract

The utility model relates to the technical field of thermo-acoustic instability research, in particular to a Rijke tube experimental device with a variable heating resistance wire, which comprises a support, a glass tube, an annular heat source, a power supply module and a control adjusting assembly. Two ends of the glass tube are opened and are vertically arranged in the middle of the bracket; the annular heat source is arranged on the inner wall of the lower area of the glass tube; the annular heat source is formed by uniformly distributing and surrounding a plurality of resistance wires circumferentially; the resistance wires are independently connected to the power supply module respectively; and the power supply module is connected to the control adjusting assembly. According to the utility model, a multi-point controllable heat source is combined with the loudspeaker and the microphone to form a closed-loop feedback system, so that the phenomenon of inconsistent heat release caused by an annular combustion chamber structure can be simulated more flexibly, and accurate thermoacoustic active control can be realized, thereby effectively controlling the phenomenon of unstable thermoacoustic in the Rijke pipe.

Description

Technical Field

[0001] The utility model relates to the technical field of thermoacoustic instability research, in particular to a Rijke tube experimental device with a variable heating resistance wire. Background Art

[0002] Currently, Rijke tube experimental setups are widely used to study thermoacoustic instabilities. Traditional Rijke tube experimental setups typically use a fixed heating source and passive acoustic feedback, making it difficult to simulate the complex thermoacoustic phenomena found in actual combustion chambers. This is particularly true of the inconsistent heat release caused by asynchronous ignition and combustion in annular combustion chambers of aircraft engines.

[0003] Chinese Patent Publication No. CN114543984A discloses a device and method for quantitatively regulating the boundary dissipation of a Rijke tube. This device quantitatively regulates the boundary dissipation of a Rijke tube through a connecting component and an impedance adjustment component. This device can adjust the dissipation and boundary reflection coefficient according to the oscillation intensity, thereby maintaining or enhancing the oscillation of the flame. However, it primarily relies on mechanically adjusting boundary conditions, which is less flexible and precise than electronic feedback control. It cannot achieve multi-point independent control and real-time adjustment, and its applicability is relatively narrow. Chinese Patent Publication No. CN118518369A discloses a multifunctional gas turbine combustion chamber thermoacoustic oscillation simulation test bench. This bench utilizes a dual Rijke tube structure and uses a modular rectifier to adjust intake conditions to meet the research needs of different experimental scenarios. However, while its modular design is flexible, it lacks precise control. Furthermore, its heat source is fixed, lacks dynamic adjustment capabilities, lacks acoustic feedback, and has low control accuracy. Chinese patent publication number CN113125503A discloses a thermoacoustic instability experimental system and method for measuring the propellant combustion response. This system and method simulates the propellant combustion response within an engine environment by heating the propellant in a Rijke tube and measuring its mass change. However, this system focuses solely on the propellant combustion process, lacks real-time acoustic feedback and multi-point heat source control, and has limited application scenarios, making it incapable of controlling and regulating complex thermoacoustic instabilities.

[0004] In summary, existing technologies often struggle to achieve flexible multi-point heating control and real-time feedback when simulating complex thermoacoustic coupling phenomena. This is particularly true when studying active control algorithms for annular combustors, as the lack of a simple, easy-to-use, and effective experimental platform makes it difficult to simulate thermoacoustic instabilities in annular combustors. Furthermore, most conventional devices lack closed-loop acoustic feedback systems, making it impossible to monitor and adjust acoustic responses in real time, limiting the verification and optimization of active control algorithms. Summary of the Invention

[0005] In response to the above problems, the purpose of the present invention is to provide a Rijke tube experimental device with a variable heating resistor wire, which can realize multi-point controllable heat sources and combine with speakers and microphones to form a closed-loop feedback system to effectively control the thermoacoustic instability phenomenon in the Rijke tube.

[0006] The technical solutions adopted in this utility model are as follows:

[0007] The utility model proposes a Rijke tube experimental device with a variable heating resistance wire, comprising a bracket, a glass tube, an annular heat source, a power module and a control and adjustment component; the glass tube is open at both ends and is vertically arranged in the middle of the bracket; the annular heat source is arranged on the inner wall of the lower area of ​​the glass tube; the annular heat source is composed of a plurality of resistance wires evenly distributed around the circumference; the resistance wires are independently connected to the power module; and the power module is connected to the control and adjustment component.

[0008] Furthermore, the control and regulation component includes a data acquisition card and a computer end; the data acquisition card is connected to the computer end; and the power supply module is connected to the data acquisition card.

[0009] Furthermore, the bracket is an aluminum profile bracket.

[0010] Furthermore, the device also includes a closed-loop acoustic feedback component; the closed-loop acoustic feedback component is arranged between the upper and lower ends of the glass tube and is connected to the data acquisition card.

[0011] Furthermore, the closed-loop acoustic feedback component includes a microphone and a speaker; the microphone is arranged above the top end of the glass tube; the speaker is arranged below the bottom end of the glass tube; the microphone and the speaker are respectively connected to a data acquisition card.

[0012] Furthermore, the microphone is connected to the data acquisition card via a microphone power amplifier.

[0013] Furthermore, the speaker is connected to the data acquisition card via a speaker power amplifier.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] This invention addresses the challenges of existing Rijke tube thermoacoustic instability research platforms, including inflexible control, lack of real-time feedback, and inability to independently control multiple heat sources. By proposing an experimental platform with independent control of multiple heat sources and a closed-loop acoustic feedback system, the platform significantly improves the accuracy and flexibility of experimental research on thermoacoustic instabilities. Through scientific analysis and experimental results, the specific technical effects are as follows:

[0016] This invention utilizes a ring-shaped resistance wire design to allow for independent heating control of multiple heat sources (six resistance wires). Compared to traditional single-point heat source control, this system can flexibly adjust the heating location and duration of the heat source according to experimental requirements, thereby simulating more complex thermoacoustic instabilities, particularly the multi-point heat release in an annular combustion chamber.

[0017] By introducing a closed-loop acoustic feedback system consisting of a microphone and a speaker into the system, the sound pressure changes inside the Rijke tube can be monitored in real time, and the acoustic input and heat source heating timing can be automatically adjusted based on the feedback data of the sound pressure oscillation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0019] Figure 2 for Figure 1 Schematic diagram of the structure of the ring resistance wire;

[0020] Figure 3 This is a schematic diagram of the circuit connection principle of the relevant components in the present utility model.

[0021] Among them, the figure marks are: 1-aluminum profile bracket; 2-glass tube; 3-ring resistance wire heat source; 4-resistance wire; 5-power module; 6-data acquisition card; 7-computer terminal; 8-microphone; 9-microphone power amplifier; 10-speaker; 11-speaker power amplifier. DETAILED DESCRIPTION

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] It should be noted that, in the description of the present invention, the terms "upper", "lower", "top", "bottom", "one side", "the other side", "left", "right", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not mean that the device or element must have a specific orientation, be constructed and operated in a specific orientation.

[0024] See attached Figure 1-3 The utility model proposes a Rijke tube experimental device with a variable heating resistance wire, which includes a bracket 1, a glass tube 2, a ring heat source 3, a power module 6 and a control and adjustment component.

[0025] The bracket 1 is an aluminum profile bracket, used to fix and support the entire platform frame and ensure stable installation of all components. The glass tube 2 is 42 cm long and 3 cm in inner diameter, with open ends at both ends and vertically fixed to the center of the bracket 1. The glass tube 2 constitutes the main experimental cavity, used to generate thermoacoustic instability. The annular heat source 3 is correspondingly arranged on the inner wall of the lower region of the glass tube 2. In this embodiment, the annular heat source 3 is composed of six arc-shaped resistance wires 4 evenly distributed around the circumference. The six resistance wires 4 are individually connected to a power module 5 via independent relays. Each relay is located inside the power module 5 and is connected to a control and adjustment component. Each resistance wire 4 is powered by the power module 5 and can be independently heated to simulate the heat source in the combustion chamber. The heating intensity and duration can be independently adjusted to generate different thermoacoustic oscillation modes.

[0026] The control and regulation assembly includes a data acquisition card 6 and a computer terminal 7. The data acquisition card 6 is connected to the computer terminal 7. The relays within the power module 5 are individually connected to the data acquisition card 6. The data acquisition card 6 is responsible for collecting acoustic data feedback from the microphone 8, adjusting the input signal of the speaker 10, and controlling the heating intensity and timing of each resistance wire 4.

[0027] In this embodiment, the device further includes a closed-loop acoustic feedback component; the closed-loop acoustic feedback component includes a microphone 8 and a speaker 10; the microphone 8 is correspondingly arranged above the top end of the glass tube 2 and is used to collect the acoustic output signal within the system; the speaker 10 is correspondingly arranged below the bottom end of the glass tube 2 and serves as an acoustic signal input source;

[0028] The microphone 8 is connected to the data acquisition card 6 via a microphone power amplifier 9 and driven by the microphone power amplifier 9 to monitor the sound pressure changes within the glass tube 2 in real time. The speaker 10 is connected to the data acquisition card 6 via a speaker power amplifier 11 and driven by the speaker power amplifier 11, and adjusts the input acoustic signal through the computer terminal 7. The microphone 8 transmits the collected sound pressure signal to the computer terminal 7 in real time via the data acquisition card 6. The computer terminal 7 adjusts the input signal to the speaker 10 according to the algorithm of the computer terminal 7, forming a closed-loop feedback loop.

[0029] The microphone power amplifier 9 and the speaker power amplifier 11 are connected to the power supply module 5 respectively.

[0030] The data acquisition card 6 receives the sound pressure signal feedback from the microphone 8 and transmits the collected data to the computer terminal 7 for analysis; the computer terminal 7 adjusts the heating power of the resistance wire 4 and the acoustic input signal of the speaker 10 according to the feedback data, thereby realizing real-time control of the thermoacoustic instability phenomenon.

[0031] The working principle of the present invention is as follows: by controlling the heating of the resistance wire 4, thermoacoustic instability is generated; microphone 8 monitors the sound pressure changes in real time, and the data is transmitted to computer terminal 7 for processing. Computer terminal 7 controls the input signal of speaker 10 and the heating timing of resistance wire 4 through data acquisition card 6, thereby realizing dynamic regulation of thermoacoustic phenomenon.

[0032] Independent Control of Multiple Heat Sources: Independent control of each resistor 4 allows for simulation of complex thermoacoustic instabilities, particularly suitable for simulating thermoacoustic oscillations in annular combustion chambers. Controlled by the power module 5, each resistor 4 can be independently adjusted, improving the accuracy of thermoacoustic instabilities.

[0033] Algorithm verification: By adjusting the heating power of the resistor 4 and the acoustic input of the speaker 10, the device can simulate different thermoacoustic instabilities. In conjunction with the real-time data feedback from the microphone 8, it is used to verify and debug the effectiveness of the active control algorithm in suppressing or exciting oscillations.

[0034] Matters not described in detail in this utility model are known technologies.

[0035] The embodiments described above are merely descriptions of preferred implementation methods of the present invention and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A Rijke tube experimental device with a variable heating resistance wire, characterized by: The device includes a bracket, a glass tube, an annular heat source, a power module and a control and adjustment component; the glass tube is open at both ends and is vertically arranged in the middle of the bracket; the annular heat source is arranged on the inner wall of the lower area of ​​the glass tube; the annular heat source is composed of a plurality of resistance wires evenly distributed around the circumference; the resistance wires are independently connected to the power module; and the power module is connected to the control and adjustment component.

2. The Rijke tube experimental device with a variable heating resistance wire according to claim 1, characterized in that: The control and regulation component comprises a data acquisition card and a computer terminal; the data acquisition card is connected to the computer terminal; and the power supply module is connected to the data acquisition card.

3. The Rijke tube experimental device with a variable heating resistance wire according to claim 1, characterized in that: The bracket is an aluminum profile bracket.

4. The Rijke tube experimental device with a variable heating resistance wire according to claim 2, characterized in that: The device also includes a closed-loop acoustic feedback component; the closed-loop acoustic feedback component is arranged between the upper and lower ends of the glass tube and is connected to the data acquisition card.

5. The Rijke tube experimental device with a variable heating resistance wire according to claim 4, characterized in that: The closed-loop acoustic feedback component includes a microphone and a speaker; the microphone is arranged above the top end of the glass tube; the speaker is arranged below the bottom end of the glass tube; the microphone and the speaker are respectively connected to a data acquisition card.

6. The Rijke tube experimental device with a variable heating resistance wire according to claim 5, characterized in that: The microphone is connected to the data acquisition card through a microphone power amplifier, and the microphone power amplifier is connected to the power module.

7. A Rijke tube experimental device with a variable heating resistance wire according to claim 5 or 6, characterized in that: The loudspeaker is connected to the data acquisition card via a loudspeaker power amplifier, and the loudspeaker power amplifier is connected to the power module.

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