Thermoacoustic power generation system

Abstract

This invention provides a thermoacoustic power generation system that can improve the power generation efficiency of a linear generator. The thermoacoustic power generation system includes: a linear generator having a permanent magnet, a coil, an inner yoke, an outer yoke, two pistons, and two cylinders. The permanent magnet is disposed on the inner yoke, the coil is disposed on the outer yoke, and the two pistons are respectively located at both ends of the inner yoke; and two thermoacoustic components, each of which includes an annular tube and a prime mover. The annular tube is connected to the linear generator via a resonant tube. The prime mover is disposed within the annular tube and includes a cooler, a heat accumulator, and a heater arranged in sequence. The volume of the annular tube in one of the two thermoacoustic components is the same as the volume of the annular tube in the other thermoacoustic component. The two thermoacoustic components are arranged opposite each other with opposite phases to drive the two pistons to vibrate back and forth within the two cylinders to convert acoustic energy into electrical energy.

Description

Technical Field

[0001] This utility model relates to a power generation system, and more particularly to a thermoacoustic power generation system. Background Technology

[0002] In recent years, research and development efforts have been made to contribute to energy efficiency in order to ensure access to affordable, reliable, sustainable and advanced energy for more people.

[0003] In existing technology, a thermoacoustic generator has been proposed, which converts the thermal energy from the prime mover of a thermoacoustic component into mechanical energy in the form of sound waves. This mechanical energy drives the piston of a linear generator to reciprocate along its central axis, thereby enabling the linear generator to further convert the mechanical energy into electrical energy output. However, in existing thermoacoustic power generation systems, the volume difference between the thermoacoustic component and the linear generator results in a difference in their air spring constants. This makes it difficult for the operating frequency of the thermoacoustic component to match the natural frequency of the linear generator, which is detrimental to improving the power generation efficiency of the linear generator. Therefore, it is necessary to improve the thermoacoustic power generation system to overcome the above problems. Utility Model Content

[0004] This invention provides a thermoacoustic power generation system that can improve the power generation efficiency of a linear generator.

[0005] According to an embodiment of this utility model, a thermoacoustic power generation system includes: a linear generator having a permanent magnet, a coil, an inner yoke, an outer yoke, two pistons, and two cylinders; the permanent magnet is disposed on the inner yoke, the coil is disposed on the outer yoke, and the two pistons are respectively located at both ends of the inner yoke; and two thermoacoustic components, each of the two thermoacoustic components including an annular tube and a prime mover; the annular tube is connected to the linear generator through a resonant tube; the prime mover is disposed within the annular tube and includes a cooler, a heat accumulator, and a heater arranged in sequence; the volume of the annular tube of one of the two thermoacoustic components is the same as the volume of the annular tube of the other of the two thermoacoustic components; the two thermoacoustic components are arranged opposite each other with opposite phases to drive the two pistons to vibrate back and forth within the two cylinders to convert acoustic energy into electrical energy.

[0006] In an embodiment according to the present invention, each of the two pistons has a diaphragm, the linear generator has a diaphragm chamber for accommodating the diaphragm, and each of the two pistons covers the diaphragm chamber in a manner that does not expose the diaphragm chamber.

[0007] In an embodiment according to the present invention, each of the two pistons includes a pair of cup-shaped members, and the diaphragm is held by mating surfaces of the pair of cup-shaped members that are opposite to each other.

[0008] In an embodiment according to the present invention, each of the two pistons further includes a cover member having a flat surface, the cover member covering one of the pair of cup-shaped members, and the flat surface of the cover member forming an acoustic pressure-bearing portion of each of the two pistons.

[0009] Based on the above, in the thermoacoustic power generation system of this invention, pistons are installed at both ends of the inner yoke of the linear generator, and two thermoacoustic components with the same volume and opposite phase are connected to the linear generator to drive the inner yoke and the two pistons in reciprocating motion. Accordingly, during the movement of the two pistons, when the air in one of the two thermoacoustic components is compressed by the corresponding piston, the air in the other thermoacoustic component expands, ensuring that the acoustic energy of the two thermoacoustic components does not resist each other. Furthermore, the same volume of the two thermoacoustic components results in the same air spring constant, allowing the operating frequencies of the two thermoacoustic components to match each other and easily conform to the natural frequency of the linear generator. Therefore, the thermoacoustic power generation system of this invention can improve the power generation efficiency of the linear generator.

[0010] To make the above-mentioned features and advantages of this utility model more apparent and understandable, specific embodiments are described below, and detailed descriptions are provided in conjunction with the accompanying drawings. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of a thermoacoustic power generation system according to an embodiment of the present invention;

[0012] Figure 2A and Figure 2B Show Figure 1 The operating mode of a linear generator;

[0013] Figure 3 yes Figure 1 An enlarged view of the thermoacoustic power generation system at the piston;

[0014] Figure 4 Show Figure 3 A cover component is added to the piston.

[0015] Explanation of reference numerals in the attached figures:

[0016] 10: Linear Generator

[0017] 11: Piston

[0018] 11a, 11b: Cup-shaped components

[0019] 11c: Cover component

[0020] 12: Cylinder block

[0021] 12a: Diaphragm chamber

[0022] 13: Pressure Vessel

[0023] 14: Inner yoke

[0024] 15: External yoke

[0025] 20: Thermoacoustic components

[0026] 100: Thermoacoustic power generation system

[0027] 110: Circular pipe

[0028] 120: Prime Motion Machine

[0029] 121: Heat accumulator

[0030] 122: Cooler

[0031] 123: Heater

[0032] 130: Resonant tube

[0033] CL: Coil

[0034] DF: Diaphragm

[0035] PM: Permanent magnet

[0036] S1, S2: Itinerary Detailed Implementation

[0037] Figure 1 This is a schematic diagram of a thermoacoustic power generation system according to an embodiment of the present invention. Please refer to... Figure 1 The thermoacoustic power generation system 100 of this embodiment includes a linear generator 10 and two thermoacoustic components 20. Each thermoacoustic component 20 includes an annular tube 110, a prime mover 120, and a resonant tube 130. In this embodiment, the annular tube 110 is sealed with a working gas. Figure 1 As shown, in this embodiment, the prime mover 120 is disposed in the annular tube 110 and includes a cooler 122, a heat accumulator 121 and a heater 123 arranged sequentially along the tube axis of the annular tube 110. The heat accumulator 121 is installed in the annular tube 110 and is a narrow flow channel. The heater 123 is disposed at one end of the heat accumulator 121 and the cooler 122 is disposed at the other end of the heat accumulator 121.

[0038] On the other hand, one end of the resonant tube 130 is connected to the annular tube 110, and the other end of the resonant tube 130 is connected to the linear generator 10. That is, the annular tube 110 is connected to the linear generator 10 through the resonant tube 130. Specifically, in this embodiment, the thermoacoustic assembly 20 generates a temperature gradient through the heaters 123 and coolers 122 at both ends of the heat accumulator 121. When the temperature ratio at both ends of the heat accumulator 121 exceeds a certain critical value, the working gas in the pipe generates self-excited vibration, so that the thermal energy is converted into acoustic energy in the prime mover 120 and is transferred to the linear generator 10 through the annular tube 110 and the resonant tube 130.

[0039] Furthermore, such as Figure 1 As shown, in this embodiment, the linear generator 10 includes two pistons 11, two cylinders 12, a pressure vessel 13, a permanent magnet PM, a coil CL, an inner yoke 14, and an outer yoke 15. Specifically, the two pistons 11 are located at opposite ends of the inner yoke 14, and the two cylinders 12 are respectively disposed at opposite ends of the pressure vessel 13. At least a portion of each piston 11 is located in the corresponding cylinder 12 and can reciprocate within the cylinder 12. The inner yoke 14 moves together with the two pistons 11. The permanent magnet PM is disposed in the inner yoke 14, and the coil CL is disposed in the outer yoke 15. The pressure vessel 13 has an internal space for accommodating the coil CL and the permanent magnet PM. When the acoustic energy generated in the annular tube 110 is transmitted to the linear generator 10 through the resonant tube 130, the pistons 11 vibrate back and forth within the cylinders 12, driving the magnetic yoke in the linear generator 10. Through the movement of the magnetic yoke in the linear generator 10, the magnetic flux of the permanent magnet PM in the coil CL changes, generating an electromotive force. In this way, acoustic energy is converted into electrical energy in the linear generator 10.

[0040] In this embodiment, the volume of the annular tube 110 of one of the two thermoacoustic components 20 is the same as the volume of the annular tube 110 of the other of the two thermoacoustic components 20. The two thermoacoustic components 20 are arranged opposite each other with opposite phases (i.e., the sound waves of the two thermoacoustic components 20 are 180 degrees out of phase) to drive the two pistons 11 to vibrate back and forth in the two cylinders 12 respectively to convert sound energy into electrical energy.

[0041] Figure 2A and Figure 2B Show Figure 1 The operation mode of the linear generator. As described above, in the thermoacoustic power generation system 100 of this embodiment, pistons 11 are provided at both ends of the inner yoke 14 of the linear generator 10, and two thermoacoustic components 20 with the same volume and opposite phase are connected to the linear generator 10 to drive the inner yoke 14 and the two pistons 11 to... Figure 2A The itinerary S1 and shown Figure 2B The stroke S2 ​​shown is a reciprocating motion. Accordingly, during the movement of the two pistons 11, when the inner yoke 14 and piston 11... Figure 2A As shown, when the leftward movement of the stroke S1 causes the air in the left thermoacoustic assembly 20 to be compressed by the corresponding piston 11, the air in the right thermoacoustic assembly 20 expands, and when the inner yoke 14 and piston 11 move to the left... Figure 2B As shown, when the thermoacoustic component 20 moves to the right during stroke S2, and the air inside the right thermoacoustic component 20 is compressed by the corresponding piston 11, the air inside the left thermoacoustic component 20 expands, ensuring that the acoustic energy of the two thermoacoustic components 20 does not resist each other. Furthermore, since the two thermoacoustic components 20 have the same volume, their air spring constants are the same, allowing their operating frequencies to match and easily conform to the natural frequency of the linear generator 10. Therefore, the thermoacoustic power generation system 100 of this embodiment can improve the power generation efficiency of the linear generator 10.

[0042] Figure 3 yes Figure 1 The enlarged view of the thermoacoustic power generation system at the piston shows, more specifically, the detailed structure of the thermoacoustic power generation system 100 near the piston 11. Please refer to... Figure 3 In this embodiment, each of the two pistons 11 has a diaphragm DF, and the linear generator 10 has a diaphragm chamber 12a for housing the diaphragm DF. Each of the two pistons 11 covers the diaphragm chamber 12a in a manner that does not expose it. Thus, even during the reciprocating vibration of the piston 11 within the cylinder 12, the outer diameter (i.e., end) of the diaphragm DF will not be exposed, thereby blocking the communication between the resonant tube 130 and other parts of the linear generator 10. Furthermore, by increasing the contact area between the piston 11 and the inner wall of the cylinder 12 (i.e., increasing the thickness of the piston 11) to prevent the diaphragm chamber 12a from being exposed, the diameter of the piston near the front of the resonant tube 130 will not change due to the reciprocating vibration of the piston 11 within the cylinder 12. This avoids changes in the inner diameter of the pipe and prevents changes in the impedance of the sound waves, which is beneficial for energy conversion and thus improves the power generation efficiency of the linear generator 10.

[0043] In addition, such as Figure 3 As shown, in this embodiment, each of the two pistons 11 includes a pair of cup-shaped members 11a and 11b, and the diaphragm DF is held by the mating surfaces of the cup-shaped members 11a and 11b. Thus, by the contour arrangement of the cup-shaped members 11a and 11b, even if the thickness of the piston 11 is increased, the increase in the weight of the piston 11 can be suppressed, and the inherent value of the vibration characteristics of the piston 11 structure can be increased.

[0044] Figure 4 Show Figure 3 A cover component is added to the piston. Figure 4In one embodiment, the piston 11 of the linear generator 10 may further include a cover member 11c with a flat surface, the cover member 11c covering the cup-shaped member 11b, and the flat surface of the cover member 11c forming the acoustic wave pressure-bearing portion of the piston 11. Thus, the cup-shaped member 11b near the resonant tube 130 in the piston 11 is covered by the cover member 11c, which flattens the acoustic wave pressure-bearing portion of the piston 11, allowing it to easily align with the antinodes of the pressure amplitude, effectively utilizing the pressure-bearing surface, and simultaneously suppressing an increase in the weight of the piston 11.

[0045] In summary, in the thermoacoustic power generation system of this invention, pistons are installed at both ends of the inner yoke of the linear generator, and two thermoacoustic components with the same volume and opposite phase are connected to the linear generator to drive the inner yoke and the two pistons in reciprocating motion. Accordingly, during the movement of the two pistons, when the air in one of the two thermoacoustic components is compressed by the corresponding piston, the air in the other thermoacoustic component expands, ensuring that the acoustic energy of the two thermoacoustic components does not resist each other. Furthermore, the same volume of the two thermoacoustic components results in the same air spring constant, allowing the operating frequencies of the two thermoacoustic components to match and easily conform to the natural frequency of the linear generator. Therefore, the thermoacoustic power generation system of this invention can improve the power generation efficiency of the linear generator.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A thermoacoustic power generation system, characterized in that, include: A linear generator comprises a permanent magnet, a coil, an inner yoke, an outer yoke, two pistons, and two cylinders. The permanent magnet is disposed on the inner yoke, the coil is disposed on the outer yoke, and the two pistons are respectively located at both ends of the inner yoke. The system comprises two thermoacoustic components, each including a ring tube and a prime mover. The ring tube is connected to the linear generator via a resonant tube. The prime mover is disposed within the ring tube and includes a cooler, a heat accumulator, and a heater arranged in sequence. The volume of the annular tube in one of the two thermoacoustic components is the same as the volume of the annular tube in the other of the two thermoacoustic components. The two thermoacoustic components are arranged opposite each other with opposite phases to drive the two pistons to vibrate back and forth in the two cylinders respectively to convert acoustic energy into electrical energy.

2. The thermoacoustic power generation system according to claim 1, characterized in that, Each of the two pistons has a diaphragm. The linear generator has a diaphragm chamber for housing the diaphragm. Each of the two pistons covers the diaphragm chamber in a manner that does not expose the diaphragm chamber.

3. The thermoacoustic power generation system according to claim 2, characterized in that, Each of the two pistons includes a pair of cup-shaped members, and the diaphragm is held by mating surfaces of the pair of cup-shaped members that are opposite to each other.

4. The thermoacoustic power generation system according to claim 3, characterized in that, Each of the two pistons further includes a cover member having a flat surface, the cover member covering one of the pair of cup-shaped members, and the flat surface of the cover member forming the acoustic pressure portion of each of the two pistons.

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