Phase change thermoacoustic engine experimental device

Abstract

The utility model relates to a phase change thermo-acoustic engine experimental device which comprises a thermo-acoustic conversion system and an acoustic-electric conversion system. The thermo-acoustic conversion system comprises a sound production module and a Helmholtz resonant cavity, a ceramic plate stack soaked with water exists in the sound production module, and the stable temperature difference needed for generating the thermo-acoustic effect at the two ends of the ceramic plate stack is reduced. Sound waves generated by the thermoacoustic effect form standing waves in the Helmholtz resonant cavity, and the sound intensity is amplified; the acoustic-electric conversion system comprises piezoelectric ceramics and a triode common-emitter amplification circuit, the piezoelectric ceramics are arranged at the tail end of the resonant cavity and convert acoustic energy into electric energy, and the electric energy is amplified by the triode common-emitter amplification circuit and then drives a nixie tube to display. The experimental device integrates thermodynamics, fluid mechanics, acoustics, material science and electronic technology, has the characteristics of simple structure, low cost, rich physical process and strong exploration, is suitable for experimental teaching, particularly suitable for new engineering teaching requirements, and is beneficial to improving the multidisciplinary cross practice ability of students.

Description

Technical Field

[0001] This utility model belongs to the technical field of physics inquiry experimental teaching devices, and particularly relates to an experimental teaching device for phase change thermoacoustic engines. Background Technology

[0002] The thermoacoustic effect was first discovered in the 18th century when glassblowers observed that when a hot glass bulb was connected to a cooler glass tube, the tube produced a sound. Subsequent systematic experimental investigations, such as the Sondhaus tube, Rijke tube, and Taconis tube, followed. However, subsequent research on this thermoacoustic effect lacked practical applications until Carter's invention of cordierite ceramic plates in 1962 and Ceperley's invention of the thermoacoustic accumulator in 1979, which transformed thermoacoustic devices into engines with usable sound power output (Thermoacoustic engine, TAE). Today, the thermoacoustic effect generally refers to the physical process of converting heat energy into sound energy due to a temperature difference or using sound waves to generate a temperature difference.

[0003] In university physics experiments, thermodynamics experiments are relatively few, and the content often remains unchanged for years. Air heat engines are one of the thermodynamic experiments in some universities, and most demonstrations show the working principle of the heat engine. Because the heat source is an alcohol lamp, quantitative measurements are not possible. To help students gain a deeper understanding of the heat cycle process and related theories in heat engines, such as... Figure 1 The image shows an air heat engine experimental apparatus proposed in the patent (publication number: CN208315042U) by Pan Jing et al. It uses electric heating and can measure parameters such as temperature difference, input power, and PV cycle diagram in a relatively quantitative manner. However, the physical process of the heat engine is relatively simple and the experimental content is not rich enough.

[0004] In the scientific research field, current gas-liquid phase change thermoacoustic engines can achieve experimental schemes with low temperature differences and high efficiency, but the equipment and manufacturing processes are demanding, preventing their application in practical production and daily life. In the industrial field, for example... Figure 2 The image shows a thermoacoustic driven low-grade heat exchanger proposed in a patent (publication number: CN105865080A) by Tang Ke et al. These devices use organic solvents (dimethyl carbonate, ethanol, or acetone, etc.) as phase change media, are relatively large (typically on the order of ten meters), and their chambers are mostly sealed and pressure-resistant steel. Phase change media are mostly toxic, and the engine structure is complex, the manufacturing process is cumbersome, and the cost is high, making them unsuitable for use in experimental teaching. Summary of the Invention

[0005] The technical problem solved by this utility model is achieved through the following technical solution:

[0006] This utility model relates to an experimental teaching device for a phase change thermoacoustic engine, including a thermoacoustic conversion system and a sound-to-electric conversion system. The thermoacoustic conversion system includes a sound-generating module and a Helmholtz resonant cavity. The sound-generating module contains a cordierite ceramic plate stack soaked in water. The wet cordierite ceramic plate stack surface, through the rapid heat conduction of water, can more quickly transfer heat from the hot end to the cold end, resulting in more sufficient thermal contact between the working gas and the cordierite ceramic plate stack. This highly efficient thermal coupling significantly enhances the heat exchange efficiency between the cordierite ceramic plate stack and the surrounding gas, allowing a small temperature gradient to drive sufficiently strong gas expansion / contraction. This reduces the stable temperature difference required between the two ends of the cordierite ceramic plate stack. Under the drive of the temperature difference, the micro-gas clusters in the porous structure of the cordierite ceramic plate stack realize a Stirling cycle and output acoustic energy. Then, the sound wave forms a standing wave in the Helmholtz resonant cavity, and the sound intensity is amplified. In the acoustic-to-electric conversion system, the sound drives the piezoelectric ceramic placed at the end of the resonant cavity to vibrate, thereby converting the output acoustic energy into electrical energy. Then, through a common-emitter transistor amplifier circuit, the electrical energy is amplified and output to light up the digital tube.

[0007] Furthermore, the sound-generating module of the thermoacoustic conversion system includes a quartz test tube, a stack of cordierite ceramic plates, a transformer, an electric heater, a hollow copper spiral tube, a brushless DC water pump and a water tank, and a thermocouple temperature sensor. The stack of cordierite ceramic plates is fixed inside the test tube, while the electric heater and the hollow copper spiral tube are located at both ends of the stack of cordierite ceramic plates outside the test tube. The stack of cordierite ceramic plates is uniformly soaked in water. The electric heater is suspended by a bracket, and the hollow copper spiral tube is connected to the water pump through a rubber hose, thereby applying an adjustable temperature difference on both sides of the water-absorbing cordierite ceramic plate stack.

[0008] Furthermore, at the connection between the Helmholtz resonant cavity and the test tube, a perforated acrylic plate is placed and connected by screws.

[0009] Furthermore, the acoustic-electric conversion system includes a piezoelectric ceramic, which is fixed in the center of an aluminum plate, and the aluminum plate is fixed on an acrylic slider.

[0010] Furthermore, the base with the fixed piezoelectric ceramic can be moved along the axial direction of the Helmholtz resonant cavity.

[0011] Furthermore, the sound-to-electric conversion system includes a common-emitter transistor amplifier circuit, with the input signal being a small AC signal output from a piezoelectric ceramic tube, and the output signal connected to a digital display.

[0012] Furthermore, the outer surface of the resonant cavity is affixed with length scale markings.

[0013] The advantages and positive effects of this utility model are:

[0014] 1. This utility model proposes a phase change thermoacoustic engine experimental device applicable to university physics experimental teaching. The device has a simple structure and low cost, and uses water as the phase change medium to keep the oscillation temperature low. Simultaneously, piezoelectric ceramics are used at the output end to convert acoustic energy into electrical energy. This thermoacoustic engine exhibits rich physical processes, strong exploratory value, and incorporates profound environmental protection concepts, making it suitable for experimental teaching, especially in new engineering disciplines, enhancing students' practical application ability by combining theory and practice, and improving students' overall quality.

[0015] 2. This invention has produced a phase change thermoacoustic engine device that can be applied to university physics experimental teaching, and has provided a teaching scheme applicable to university physics experiments. This research can not only broaden students' knowledge, but also deepen their understanding of interdisciplinary fields such as thermodynamics, fluid mechanics, acoustics and materials science, and has great teaching application value. Attached Figure Description

[0016] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that these drawings are designed for illustrative purposes only and are not intended to limit the scope of this utility model. In addition, unless otherwise specified, these drawings are intended only to conceptually illustrate the structural construction described herein and are not necessarily drawn to scale.

[0017] Figure 1 A schematic diagram of the air-heat engine experimental apparatus proposed in the patent of Pan Jing et al.;

[0018] Figure 2 A schematic diagram of the structure of the thermoacoustic driven low-grade heat energy converter proposed in the patent of Tang Ke et al.

[0019] Figure 3 This is a schematic diagram of the structure of the experimental teaching device for the phase change thermoacoustic engine provided in Embodiment 1 of this utility model;

[0020] Figure 4 The sound pressure and gas molecule velocity distribution diagrams in the phase change thermoacoustic engine experimental teaching device provided in Embodiment 1 of this utility model;

[0021] Figure 5 This is a schematic diagram of the structure of the experimental teaching device for the phase change thermoacoustic engine provided in Embodiment 2 of this utility model;

[0022] Figure 6 The sound pressure and gas molecule velocity distribution diagrams in the experimental teaching device for phase change thermoacoustic engine provided in Embodiment 2 of this utility model;

[0023] Figure 7 A schematic diagram of the experimental teaching device for a phase change thermoacoustic engine provided in Embodiment 3 of this utility model;

[0024] Figure 8 This is a schematic diagram illustrating the working principle of the cordierite ceramic plate stack in the phase change thermoacoustic engine of this utility model.

[0025] In the figure: support (1), electric heater (2), quartz test tube (3), cordierite ceramic plate stack (4), hollow copper spiral tube (5), Helmholtz resonant cavity (6), acrylic slider (7), piezoelectric ceramic (8), amplifier circuit (9), digital tube (10), circuit board (11). Detailed Implementation

[0026] First, it should be noted that the specific structure, features, and advantages of this utility model will be described in detail below by way of examples. However, all descriptions are for illustrative purposes only and should not be construed as limiting the utility model in any way. Furthermore, any single technical feature described or implied in the embodiments mentioned herein, or any single technical feature shown or implied in the accompanying drawings, can still be arbitrarily combined or deleted among these technical features (or their equivalents) to obtain more other embodiments of this utility model that may not be directly mentioned herein. Additionally, for the sake of simplifying the drawings, the same or similar technical features may be indicated only in one place in the same drawing.

[0027] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the utility model product is in use. They are only for the convenience of describing this utility model 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 utility model.

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0029] Example 1

[0030] like Figure 3The phase change thermoacoustic engine experimental teaching device provided in this embodiment is a quarter-wavelength standing wave phase change thermoacoustic engine, including a thermoacoustic conversion system. The thermoacoustic conversion system includes a sound-generating module composed of a support (1), an electric heater (2), a quartz test tube (3), a cordierite ceramic plate stack (4), and a hollow copper spiral tube (5), and a Helmholtz resonant cavity (6). The cordierite ceramic plate stack (4) is soaked in water in the sound-generating module. The surface of the moist honeycomb porous cordierite ceramic plate stack can transfer heat from the hot end to the cold end more quickly through the rapid heat conduction of water, so that the thermal contact between the working gas and the cordierite ceramic plate stack is more sufficient. This efficient thermal coupling significantly enhances the heat exchange efficiency between the cordierite ceramic plate stack and the surrounding gas, allowing a small temperature gradient to drive sufficiently strong gas expansion / contraction, thereby reducing the stable temperature difference required at both ends of the cordierite ceramic plate stack (4). The micro-air clusters in the honeycomb porous structure of the cordierite ceramic plate stack (4) realize the Stirling cycle under the drive of the temperature difference, thus enabling the output of sound energy when a lower temperature difference is provided. Then, the sound wave forms a standing wave in the cavity of the Helmholtz resonant cavity (6) and the sound intensity is amplified and directly output.

[0031] The sound-generating module also includes a transformer, a brushless DC water pump and a water tank, and a thermocouple temperature sensor. The electric heater (2) is suspended by a bracket (1), and the inner surface of the electric heater (2) is fitted over the closed end of the quartz test tube (3). The electric heater (2) is connected to the mains power supply through a transformer, so that the electric power of the electric heater (2) is adjustable and used to maintain a constant temperature of the cordierite ceramic plate stack (4) near the electric heater (2). The inner diameter of the electric heater (2) and the hollow copper spiral tube (5) is close to the outer diameter of the quartz test tube (3). The two ends of the hollow copper spiral tube (5) are connected to the water pump and the water tank respectively through rubber hoses to form a water cooling system, which is used to maintain the temperature of the cordierite ceramic plate stack (4) near the hollow copper spiral tube (5) constant. Thus, the electric heater (2) and the hollow copper spiral tube (5) apply an adjustable temperature difference to both sides of the water-absorbing cordierite ceramic plate stack (4) located in the quartz test tube (3) between the ends of the electric heater (2) and the hollow copper spiral tube (5). A temperature gradient is formed in the cordierite ceramic plate stack (4) soaked in water, which causes the gas to start self-excited oscillation to convert heat energy into sound work, which can generate a thermoacoustic effect to drive the gas working fluid to oscillate back and forth. Thermocouple temperature sensor probes are placed at both ends of the cordierite ceramic plate stack (4) in the quartz test tube (3) to measure the temperature of the cold end and the hot end in real time.

[0032] The working process of the phase change thermoacoustic engine provided in this embodiment is explained in detail below:

[0033] The cordierite ceramic plate stack (4) soaked in water is the working device for gas self-excited oscillation. The PV diagram of the gas-liquid phase change cycle process occurring at the cordierite ceramic plate stack is shown in Figure 4. Figure 8 As shown. Process 1-2 is an isobaric endothermic process: the subcooled liquid phase pure working fluid element moves from the cold end to the hot end. Because it has good thermal contact with the cordierite ceramic plate stacked wall surface, it absorbs heat from the cordierite ceramic plate stacked wall surface under isobaric conditions and is heated into a saturated liquid; Process 2-2p is an isobaric evaporation process: the saturated liquid phase working fluid element evaporates under isobaric conditions, absorbs heat from the cordierite ceramic plate stacked wall surface and becomes a saturated gas. During evaporation, the temperature of the working fluid element increases; process 2p-3 is an isothermal expansion process: due to the same temperature and lower pressure on the cordierite ceramic plate stack at its location, the saturated gaseous working fluid element further expands to a superheated gas state under isothermal conditions; process 3-4 is an isobaric exothermic process: the superheated gaseous working fluid element moves from the hot end to the cold end, releases heat to the cordierite ceramic plate stack under isobaric conditions, and is cooled into a saturated gas; process 4-4p is an isobaric condensation process: the saturated gaseous working fluid element condenses under isobaric conditions, releases heat to the cordierite ceramic plate stack and becomes a saturated liquid; process 4p-1 is an isothermal compression process: the saturated gaseous working fluid element is near the cold end, and due to the same temperature and higher pressure on the cordierite ceramic plate stack at that location, it liquefies and is further compressed into a supercooled liquid, returning to state point 1 and completing the cycle.

[0034] A first acrylic plate is provided at the open end of the quartz test tube (3), and a second acrylic plate is provided at the end of the Helmholtz resonant cavity (6) made of acrylic material near the open end of the quartz test tube (3). The two acrylic plates are the same size and thickness. The two acrylic plates are connected by four screws of the connector. The removal and installation of the screws make it easy to disassemble and assemble the quartz test tube (3) and the Helmholtz resonant cavity (6), thereby facilitating the placement and removal of the cordierite ceramic plate stack.

[0035] It should be noted that the volume of the Helmholtz resonant cavity (6) needs to be much larger than the volume of the quartz test tube (3) in order to achieve the amplification effect. In this embodiment, the cordierite ceramic plate stack (4) has a length of 4.00 cm and a diameter of 2.00 cm, and the bottom of the cordierite ceramic plate stack (4) is 6.00-10.00 cm away from the bottom of the quartz test tube (3), with a water content of 1.30-2.50 g; the quartz test tube (3) has a length of 20.00 cm and an inner diameter of 2.50 cm; the Helmholtz resonant cavity (6) has a length of 50.00 cm and an inner diameter of 12.00 cm.

[0036] In this embodiment, the Helmholtz resonant cavity (6) is closed at one end and open at the other end, such as Figure 4As shown, the closed end is close to the antinode of the acoustic pressure wave of the resonant oscillation, and the open end is close to the antinode of the oscillation velocity wave. When the fundamental frequency oscillates, the resonator exhibits a characteristic close to a quarter wavelength, thus it is designed as a quarter-wavelength standing wave thermoacoustic engine.

[0037] Specifically, in this embodiment, since soaking the cordierite ceramic plate stack (4) in water can significantly reduce the temperature difference oscillation and affect the output sound power, and the water content and position of the cordierite ceramic plate stack (4) can be adjusted, their influence on the temperature difference between the hot and cold ends and the output sound power during oscillation can be investigated. The adjustment of the water content requires removing the screws, separating the quartz test tube (3) from the Helmholtz resonant cavity (6), and weighing the mass change of the cordierite ceramic plate stack before and after soaking in water with an electronic balance (that is, the water content of the cordierite ceramic plate stack).

[0038] Example 2

[0039] like Figure 5 The phase change thermoacoustic engine experimental teaching device provided in this embodiment is a half-wavelength standing wave phase change thermoacoustic engine experimental teaching device. The device provided in this embodiment is basically the same as the system structure and principle provided in embodiment 1. The difference is that: a circular acrylic slider (7) that can move freely along the axis of the cavity on the track inside the Helmholtz resonant cavity (6) is placed at the right end of the cavity. The left side of the acrylic slider is a circular aluminum plate with the same radius. That is, the circular aluminum plate is set at the end of the circular acrylic slider near the quartz test tube (3). A piezoelectric ceramic (8) is fixed on the left side of the circular aluminum plate, which constitutes the sound-to-electric conversion system. The sound drives the piezoelectric ceramic (8) placed at the tail end of the resonant cavity to vibrate, so as to realize the conversion of the output sound energy into electrical energy. At this time, both ends of the Helmholtz resonant cavity (6) are closed, such as Figure 6 As shown, the closed end can only exhibit the antinode of sound pressure (node ​​of velocity) during resonant oscillation. The sound field distribution is dominated by standing wave state. When the fundamental frequency oscillates, the Helmholtz resonant cavity exhibits a near half-wavelength characteristic, thus it is designed as a half-wavelength standing wave thermoacoustic engine.

[0040] Specifically, in this embodiment, the parameters, quantity, and connection method of the piezoelectric ceramic (8) are adjustable. A loudspeaker can be used to sweep frequencies to obtain the resonant frequencies of different piezoelectric ceramics, and the piezoelectric ceramic with the resonant frequency closest to the sound wave frequency can be selected to achieve the maximum conversion efficiency. Multiple piezoelectric ceramic sheets can be connected in series or parallel using wires to ensure the largest possible sound-receiving area, thereby improving the sound-to-electric conversion efficiency.

[0041] The thickness ratio and area ratio of the piezoelectric ceramic (8) and the acrylic slider (7) can also be adjusted. Different thickness ratios and area ratios correspond to different acoustic-electric conversion efficiencies. According to theory, the acoustic-electric conversion efficiency is maximized when the radius ratio of the piezoelectric ceramic to the metal substrate (a circular aluminum plate in this utility model) is 0.5 to 0.7 and the thickness ratio of the piezoelectric ceramic to the metal substrate is 2.5 to 3.2.

[0042] By connecting an oscilloscope to both ends of the piezoelectric ceramic (8), a standard sine wave can be observed, and the waveform frequency is consistent with the sound wave frequency.

[0043] The other structures and adjustment methods in this embodiment are the same as those in Embodiment 1, so they will not be described again here.

[0044] Example 3

[0045] like Figure 7 The phase change thermoacoustic engine experimental teaching device provided in this embodiment is a half-wavelength standing wave phase change thermoacoustic engine experimental teaching device, which is a further improvement and supplement to embodiment 2. Based on the system structure and principle provided in embodiment 2, the device provided in this embodiment connects the piezoelectric ceramic (8) to the signal amplification component composed of an amplification circuit (9), a digital tube (10), and a circuit board (11). The sinusoidal AC small signal voltage output by the piezoelectric ceramic is input to the amplification circuit (9) composed of a transistor, an integrated operational amplifier, or a power amplifier to obtain an amplified AC voltage. This voltage is close to the rated voltage of the digital tube, which lights up the digital tube and can display various letter combination patterns, i.e., display signals.

[0046] The above embodiments have provided a detailed description of the present invention, but the content described is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made in accordance with the claims of the present invention should still fall within the patent coverage of the present invention.

Claims

1. An experimental apparatus for a phase change thermoacoustic engine, characterized in that: Including thermoacoustic conversion systems; The thermoacoustic conversion system includes a sound-generating module and a Helmholtz resonant cavity (6). The sound-generating module includes a support (1), an electric heater (2), a quartz test tube (3), a cordierite ceramic plate stack (4), a hollow copper spiral tube (5), a brushless DC water pump, and a water tank. The electric heater (2) is mounted on the support, and the inner surface of the electric heater (2) is fitted over the closed end of the quartz test tube (3); the open end of the quartz test tube (3) is connected to the Helmholtz resonant cavity (6); the quartz test tube (3) located between the electric heater (2) and the Helmholtz resonant cavity (6) is surrounded by the hollow copper spiral tube (5); the two ends of the hollow copper spiral tube (5) are respectively connected to the brushless DC water pump and the water tank; a cordierite ceramic plate stack (4) is provided inside the quartz test tube (3) located between the electric heater (2) and the end of the hollow copper spiral tube (5), and the cordierite ceramic plate stack (4) is uniformly soaked in water; When the electric heater (2) is heating, the electric heater (2) is used to maintain a constant temperature at one end of the cordierite ceramic plate stack (4) near the electric heater (2); the hollow copper spiral tube (5), the brushless DC water pump and the water tank form a water cooling system to maintain a constant temperature at one end of the cordierite ceramic plate stack (4) near the hollow copper spiral tube (5); the micro air clusters inside the cordierite ceramic plate stack (4) convert thermal energy into acoustic energy through the Stirling cycle and are transmitted to the Helmholtz resonant cavity through the quartz test tube (3).

2. The experimental apparatus for a phase change thermoacoustic engine according to claim 1, characterized in that, The quartz test tube (3) has a first acrylic plate at its open end, and the Helmholtz resonant cavity (6) has a second acrylic plate at one end near the open end of the quartz test tube (3). The first acrylic plate and the second acrylic plate are connected by a connector.

3. The experimental apparatus for a phase change thermoacoustic engine according to claim 1, characterized in that, The device also includes a sound-to-electric conversion system; the sound-to-electric conversion system includes a sound driving component and a signal amplification component; The sound driving component includes an acrylic slider (7), a piezoelectric ceramic (8), and an aluminum plate; wherein, the acrylic slider (7) is disposed in the cavity of the Helmholtz resonant cavity (6) at one end away from the opening end of the quartz test tube (3), the aluminum plate is fixed on the acrylic slider (7), the piezoelectric ceramic (8) is fixed on the aluminum plate, and the piezoelectric ceramic (8) is used to convert the sound energy in the Helmholtz resonant cavity (6) into electrical energy; The signal amplification component includes an amplification circuit (9) and a circuit board (11); wherein the amplification circuit (9) is disposed on the circuit board (11) and the amplification circuit (9) is connected to the piezoelectric ceramic (8).

4. The experimental apparatus for a phase change thermoacoustic engine according to claim 3, characterized in that, The signal amplification component also includes a digital tube (10); the digital tube (10) is located on the circuit board (11) and connected to the amplification circuit (9). When the amplified AC voltage output by the amplification circuit (9) is input to the digital tube (10), the digital tube (10) can be used to display the signal.

5. The experimental apparatus for a phase change thermoacoustic engine according to claim 3, characterized in that, The piezoelectric ceramic (8) can move freely along the cavity axis of the Helmholtz resonant cavity (6) under the action of the acrylic slider (7) and the aluminum plate.

6. The experimental apparatus for a phase change thermoacoustic engine according to claim 5, characterized in that, The aluminum plate is a circular aluminum plate, and the acrylic slider (7) is an annular acrylic slider. The circular aluminum plate and the annular acrylic slider have the same radius. The circular aluminum plate is located at one end of the annular acrylic slider near the quartz test tube (3). The piezoelectric ceramic (8) is fixed in the center of the circular aluminum plate.

7. The experimental apparatus for a phase change thermoacoustic engine according to claim 3, characterized in that, The amplifier circuit (9) includes a common-emitter transistor amplifier circuit.

8. The experimental apparatus for a phase change thermoacoustic engine according to claim 1, characterized in that, The cordierite ceramic plate stack (4) includes a honeycomb-shaped porous cordierite ceramic plate stack.

9. The experimental device of a thermoacoustic engine with phase change according to claim 1, characterized in that, The sound-generating module also includes a temperature sensor, the probe of which is located on both sides of the cordierite ceramic plate stack (4) inside the quartz test tube (3).

10. The experimental apparatus for a phase change thermoacoustic engine according to claim 1, characterized in that, The device further includes at least one of the following: The cordierite ceramic plate stack (4) has a length of 4.00 cm, an outer diameter of 2.00 cm, and the bottom of the cordierite ceramic plate stack (4) is 6.00-10.00 cm away from the bottom of the quartz test tube (3), and the water content is 1.30-2.50 g. The quartz test tube (3) has a length of 200.0 mm and an inner diameter of 25.0 mm; The Helmholtz resonant cavity (6) has a length of 50.00 cm and an inner diameter of 12.00 cm.

Images