Thermoacoustic power generation system

Abstract

The utility model provides a thermo-acoustic power generation system which can reliably form a temperature gradient at a heat accumulator so as to improve the stability of thermo-acoustic power generation. The thermo-acoustic power generation system includes: a linear generator having a piston that vibrates within a cylinder to convert acoustic energy into electrical energy; an annular tube connected to the linear generator through the resonance tube; the prime motor is arranged in the annular pipe and comprises a cooler, a heat accumulator and a heater which are sequentially arranged, the cooler serves as a low-temperature side heat exchanger, the heater serves as a high-temperature side heat exchanger, and the heat accumulator forms a temperature gradient to generate thermo-acoustic self-excited vibration; the low-temperature side heat exchanger exchanges heat with first cooling water from the engine through a first cooling water loop, the low-temperature side heat exchanger can exchange heat with second cooling water through a second cooling water loop, and the second cooling water loop is independent of the first cooling water loop; the second cooling water is supplied to the low-temperature-side heat exchanger through the passage switching valve.

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 heat energy from a prime mover 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, if this existing thermoacoustic power generation system is applied to a vehicle, the high-temperature heat exchanger of the prime mover uses the heat from the vehicle's internal combustion engine exhaust as its heat source. The unstable output of the internal combustion engine leads to unstable temperature in the high-temperature heat exchanger, making it difficult for the thermoacoustic generator to maintain continuous operation. Therefore, it is necessary to improve the thermoacoustic power generation system to overcome these problems. Utility Model Content

[0004] This invention provides a thermoacoustic power generation system that can reliably create a temperature gradient in the heat storage device to improve the stability of thermoacoustic power generation.

[0005] According to an embodiment of the present invention, a thermoacoustic power generation system includes: a linear generator having a piston that vibrates back and forth within a cylinder to convert acoustic energy into electrical energy; an annular tube connected to the linear generator via a resonant tube; and a prime mover disposed within the annular tube and including a cooler, a heat accumulator, and a heater arranged in sequence, wherein the cooler serves as a low-temperature heat exchanger, the heater serves as a high-temperature heat exchanger, a temperature gradient is formed at both ends of the heat accumulator to generate thermoacoustic self-excited vibration, the low-temperature heat exchanger exchanges heat with a first cooling water from the engine via a first cooling water circuit, and the low-temperature heat exchanger exchanges heat with a second cooling water via a second cooling water circuit, the second cooling water circuit being independent of the first cooling water circuit. The thermoacoustic power generation system further includes a channel switching valve through which the second cooling water is supplied to the low-temperature heat exchanger.

[0006] In an embodiment of the present invention, the thermoacoustic power generation system further includes a radiator, an electric water pump, and a temperature sensor, wherein the radiator, the electric water pump, the temperature sensor, and the channel switching valve are connected in series in the second cooling water circuit.

[0007] In an embodiment of the present invention, when the temperature of the first cooling water is higher than a predetermined value, the second cooling water is supplied to the low-temperature side heat exchanger.

[0008] Based on the above, in the thermoacoustic power generation system of this invention, the low-temperature heat exchanger of the prime mover can utilize not only the first cooling water from the engine for heat exchange, but also a separately supplied second cooling water. Accordingly, when the temperature of the first cooling water from the engine exceeds a predetermined temperature due to the engine operating under high load, the low-temperature heat exchanger of the prime mover can be maintained at a sufficiently low temperature by the second cooling water, ensuring that the heat accumulator of the prime mover maintains the required temperature gradient to generate thermoacoustic self-excited vibration. Thus, the thermoacoustic power generation system of this invention can reliably form a temperature gradient in the heat accumulator to improve the stability of thermoacoustic power generation.

[0009] 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

[0010] Figure 1 This is a schematic diagram of a thermoacoustic power generation system according to an embodiment of the present invention;

[0011] Figure 2 yes Figure 1 A schematic diagram of a thermoacoustic power generation system applied to a vehicle;

[0012] Figure 3 Show Figure 2 The relationship between the flow rate and temperature of the cooling water;

[0013] Figure 4 yes Figure 3 A schematic diagram of the vehicle and some components of the thermoacoustic power generation system.

[0014] Explanation of reference numerals in the attached figures:

[0015] 10: Linear Generator

[0016] 11: Piston

[0017] 12: Cylinder block

[0018] 13: Pressure Vessel

[0019] 100: Thermoacoustic power generation system

[0020] 110: Circular pipe

[0021] 120: Prime Motion Machine

[0022] 121: Heat accumulator

[0023] 122: Cooler

[0024] 123: Heater

[0025] 130: Resonant tube

[0026] 140A, 140B: Radiator

[0027] 150A, 150B: Water pumps

[0028] 160A, 160B: Temperature sensors

[0029] 170: Electronic Control Unit

[0030] 180: Thermostat

[0031] 1000: Vehicles

[0032] 1100: Engine

[0033] C1: First cooling water circuit

[0034] C2: Second cooling water circuit

[0035] CL: Coil

[0036] CW1: First cooling water

[0037] CW2: Second Cooling Water

[0038] D: Direction

[0039] EG: Exhaust gas

[0040] F1, F1', F2, F2': Flow rate

[0041] PM: Permanent Magnet

[0042] V1, V2: Channel switching valves Detailed Implementation

[0043] 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 In this embodiment, the thermoacoustic power generation system 100 includes a linear generator 10, a ring tube 110, a prime mover 120, and a resonant tube 130. In this embodiment, the ring tube 110 is sealed with a working gas. Figure 1 As shown, in this embodiment, the prime mover 120 is disposed within the annular pipe 110 and includes a cooler 122, a heat accumulator 121, and a heater 123 arranged sequentially along the pipe axis of the annular pipe 110. The heat accumulator 121 is installed within the annular pipe 110 and forms 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. The cooler 122 serves as a low-temperature heat exchanger, and the heater 123 serves as a high-temperature heat exchanger.

[0044] 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 power generation system 100 generates a temperature gradient through the heater 123 and cooler 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 thermoacoustic self-excited vibration, so that the thermal energy is converted into acoustic energy in the prime mover 120 and transferred to the linear generator 10 through the annular tube 110 and the resonant tube 130.

[0045] Furthermore, such as Figure 1 As shown, in this embodiment, the linear generator 10 includes a piston 11, a cylinder 12, and a pressure vessel 13. Specifically, at least a portion of the piston 11 is located in the cylinder 12 and is capable of reciprocating within the cylinder 12. 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 propagates to the linear generator 10 through the resonant tube 130, it causes the piston 11 to vibrate back and forth within the cylinder 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.

[0046] Figure 2 yes Figure 1 A schematic diagram illustrating the application of a thermoacoustic power generation system in a vehicle. Please refer to the diagram. Figure 1 and Figure 2 In this embodiment, the thermoacoustic power generation system 100 is applied to the engine 1100 of the vehicle 1000. A high-temperature side heat exchanger (heater 123) exchanges heat with exhaust gas EG from the engine 1100, maintaining a high temperature using the exhaust gas EG as a heat source. A low-temperature side heat exchanger (cooler 122) exchanges heat with first cooling water CW1 from the engine 1100 of the vehicle 1000 via a first cooling water circuit C1, and can also exchange heat with second cooling water CW2 via a second cooling water circuit C2 independent of the first cooling water circuit C1, maintaining a low temperature using the first cooling water CW1 and / or the second cooling water CW2.

[0047] The thermoacoustic power generation system 100 further includes channel switching valves V1 and V2. Channel switching valve V1 is disposed in the first cooling water circuit C1, and channel switching valve V2 is disposed in the second cooling water circuit C2. First cooling water CW1 is supplied to the low-temperature side heat exchanger (cooler 122) through channel switching valve V1, and second cooling water CW2 is supplied to the low-temperature side heat exchanger (cooler 122) through channel switching valve V2. Channel switching valve V1 can control the flow rate of the first cooling water CW1 supplied to the low-temperature side heat exchanger (cooler 122), and / or open and close the supply of the first cooling water CW1 to the low-temperature side heat exchanger (cooler 122). Channel switching valve V2 can control the flow rate of the second cooling water CW2 supplied to the low-temperature side heat exchanger (cooler 122), and / or open and close the supply of the second cooling water CW2 to the low-temperature side heat exchanger (cooler 122). In some embodiments, channel switching valve V1 may be omitted, and this invention is not limited thereto.

[0048] As described above, in the thermoacoustic power generation system 100 of this embodiment, the low-temperature heat exchanger (cooler 122) of the prime mover 120 can exchange heat not only using the first cooling water CW1 from the engine 1100, but also using a separately supplied second cooling water CW2. Accordingly, when the temperature of the first cooling water CW1 from the engine 1100 exceeds a predetermined temperature due to the engine 1100 operating under high load, the low-temperature heat exchanger (cooler 122) of the prime mover 120 can still be maintained at a sufficiently low temperature by the second cooling water CW2, ensuring that the heat accumulator 121 of the prime mover 120 maintains the required temperature gradient to generate thermoacoustic self-excited vibration. Therefore, the thermoacoustic power generation system 100 of this embodiment can reliably form a temperature gradient in the heat accumulator 121 to improve the stability of thermoacoustic power generation.

[0049] Specifically, when the engine 1100 is operating under low load, exhaust gas EG is supplied to the high-temperature side heat exchanger (heater 123), first cooling water CW1 is supplied to the low-temperature side heat exchanger (cooler 122), and second cooling water CW2 is not supplied to the low-temperature side heat exchanger (cooler 122), so that the heat accumulator 121 can have the required temperature gradient. When the engine 1100 is operating under high load, the temperature of the exhaust gas EG increases and the temperature of the second cooling water CW2 increases. At this time, in addition to supplying the exhaust gas EG to the high-temperature side heat exchanger (heater 123) and the first cooling water CW1 to the low-temperature side heat exchanger (cooler 122), the second cooling water CW2 is further supplied to the low-temperature side heat exchanger (cooler 122) so that the low-temperature side heat exchanger (cooler 122) is maintained at a sufficiently low temperature, and the high-temperature side heat exchanger (heater 123) and the low-temperature side heat exchanger (cooler 122) are maintained at an appropriate temperature difference so as to reliably form a temperature gradient in the heat accumulator 121.

[0050] Figure 3 Show Figure 2 The relationship between cooling water flow rate and cooling water temperature. Please refer to... Figure 3 It can be switched via channel switching valve V1 (shown in Figure 2 ) and channel switching valve V2 (shown in Figure 2 The flow rates F1 of the first cooling water CW1 and F2 of the second cooling water CW2 are controlled respectively. Thus, as the temperature of the second cooling water CW2 gradually increases, the flow rate F1 of the first cooling water CW1 gradually decreases while the flow rate F2 of the second cooling water CW2 gradually increases, achieving the aforementioned effect of maintaining a temperature gradient. Furthermore, as... Figure 3 As shown, when the second cooling water CW2 is used as the main cooling water supplied to the low-temperature side heat exchanger (cooler 122), it is not as... Figure 3 The dashed lines (flow rates F1', F2') in the diagram generally indicate that the supply of the first cooling water CW1 is completely shut off while the supply of the second cooling water CW2 is completely turned on, but the first cooling water CW1 is maintained at a small supply. This avoids flow rate fluctuations caused by switching the coolant on / off. In other embodiments, the supply of the first cooling water CW1 and / or the second cooling water CW2 can be completely shut off / on, and this invention is not limited to this.

[0051] Figure 4 yes Figure 3 A schematic diagram of the vehicle and some components of the thermoacoustic power generation system. Please refer to... Figure 4 In detail, the thermoacoustic power generation system 100 of this embodiment (referred to as...) Figure 1 It also includes radiator 140A, radiator 140B, water pump 150A (e.g., a mechanical water pump that rotates synchronously with the engine, or an electric water pump), water pump 150B (e.g., an electric water pump), temperature sensor 160A, temperature sensor 160B, electronic control unit (ECU) 170, and thermostat 180. Channel switching valve V1, radiator 140A, water pump 150A, temperature sensor 160A, and thermostat 180 are configured in the first cooling water circuit C1. Radiator 140B, water pump 150B, temperature sensor 160B, and channel switching valve V2 are configured in series in the second cooling water circuit C2.

[0052] First cooling water CW1 (shown in) Figure 2 The water can circulate through the thermostat 180, radiator 140B, engine 1100, temperature sensor 160A, channel switching valve V1, and low-temperature side heat exchanger (cooler 122) driven by water pump 150A. Secondary cooling water CW2 (shown in...) Figure 2The water can circulate through the radiator 140B, temperature sensor 160B, channel switching valve V2 and low-temperature side heat exchanger (cooler 122) driven by the water pump 140B.

[0053] The electronic control unit 170 can determine the first cooling water CW1 (shown in the figure) based on the temperature sensor 160A. Figure 2 The temperature of the second cooling water CW2 sensed by temperature sensor 160B (shown in...) Figure 2 The temperature of the pumps 150A and 150B, channel switching valve V1 and channel switching valve V2 are used to control the water pumps 150A and 150B, and to adjust the first cooling water CW1 supplied to the hot-side heat exchanger (cooler 122) (shown in...). Figure 2 The flow rate of the second cooling water CW2 supplied to the heat exchanger (cooler 122) on the warm side (shown in the figure) and the second cooling water CW2 supplied to the heat exchanger (cooler 122) on the warm side (shown in the figure) Figure 2 ) traffic.

[0054] In summary, in the thermoacoustic power generation system of this invention, the low-temperature heat exchanger of the prime mover can utilize both the first cooling water from the engine and a separately supplied second cooling water for heat exchange. Therefore, when the temperature of the first cooling water from the engine exceeds a predetermined temperature due to high engine load, the low-temperature heat exchanger of the prime mover can still be maintained at a sufficiently low temperature by the second cooling water, ensuring that the heat accumulator of the prime mover maintains the required temperature gradient to generate thermoacoustic self-excited vibration. Thus, the thermoacoustic power generation system of this invention can reliably form a temperature gradient in the heat accumulator to improve the stability of thermoacoustic power generation.

[0055] 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 having a piston that vibrates back and forth within a cylinder to convert acoustic energy into electrical energy; A ring tube is connected to the linear generator via a resonant tube; as well as The prime mover, located within the annular tube, includes a cooler, a heat accumulator, and a heater arranged in sequence. The cooler serves as a low-temperature heat exchanger, the heater as a high-temperature heat exchanger, and a temperature gradient is formed at both ends of the heat accumulator to generate thermoacoustic self-excited vibration. The low-temperature side heat exchanger exchanges heat with the first cooling water from the engine through the first cooling water circuit. The low-temperature side heat exchanger can exchange heat with a second cooling water circuit, which is independent of the first cooling water circuit. The thermoacoustic power generation system also includes a channel switching valve, through which the second cooling water is supplied to the low-temperature side heat exchanger.

2. The thermoacoustic power generation system according to claim 1, characterized in that, It also includes radiators, electric water pumps, and temperature sensors. The radiator, the electric water pump, the temperature sensor, and the channel switching valve are connected in series in the second cooling water circuit.

3. The thermoacoustic power generation system according to claim 1, characterized in that, When the temperature of the first cooling water exceeds a predetermined value, the second cooling water is supplied to the low-temperature side heat exchanger.

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