Thermoacoustic system and method for controlling thermoacoustic system

Abstract

To provide a thermoacoustic system which can attain a desired output with a simple structure even if temperature fluctuation occurs in a heat source, and to provide a control method of the thermoacoustic system.SOLUTION: A thermoacoustic system utilizes vibration flow traveling in a pipeline with a fixed pipeline length and includes: at least one or more thermoacoustic devices for a prime mover which generates / amplifies work flow in the pipeline by supply of heat; an output part into which the work flow generated / amplified by the thermoacoustic device is input and from which an output is taken out; an adjustment part which is connected to the pipeline to adjust at least one of the work flow of the vibration flow and an acoustic field; a first detection part which detects change of a parameter in the thermoacoustic device; a control part; and a second detection part which detects an output value of the output part. The adjustment part has a drive part which provides the vibration flow into the pipeline. The control part controls the adjustment part to adjust the output of the output part so that the output becomes a setting value based on a first output value of the first detection part and a second output value of the second detection part.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a thermoacoustic system and a method for controlling a thermoacoustic system. [Background technology]

[0002] Technologies for reusing waste heat from factories, cars, etc. are being researched. One possible way to regenerate waste heat is to use an external combustion engine. Known examples of external combustion engines include steam turbines that use the Rankine cycle and Stirling engines that use the Stirling cycle. These external combustion engines are configured to extract power from a heat source.

[0003] As another type of external combustion engine, a thermoacoustic engine equipped with a heat storage device that uses an oscillating flow to convert energy between a work flow and a heat flow is known. Here, we will explain the thermoacoustic engine as an example of an oscillating-flow type external combustion engine. A thermoacoustic engine can utilize heat without having any moving parts, as the compression and expansion of the oscillating flow plays the role of a piston. The structure of a thermoacoustic engine is equipped with a porous body (heat storage device) equipped with one to an infinite number of narrow flow paths, a heat exchanger having a pair of heat absorption and radiation parts that absorb and release heat from and to the outside, and a pipe through which a working gas flows, connected to the upstream and downstream sides of the heat exchanger. When a predetermined temperature gradient (temperature difference) exceeding the critical condition is applied to this heat storage device along the axial direction of the flow path, a work flow is generated and amplified.

[0004] In a thermoacoustic engine, energy conversion between heat and work takes place inside the heat storage tank, and work can be extracted from the heat as acoustic power (work flow) possessed by sound waves. In particular, in a traveling-wave thermoacoustic engine that uses traveling-wave sound waves, the thermodynamic cycle of energy conversion is similar to the Stirling cycle, so there is a possibility that thermal efficiency can be improved. For this reason, traveling-wave thermoacoustic engines have attracted attention as heat engines that have no moving parts and are capable of waste heat recovery.

[0005] One possible method for extracting the work flow generated by the thermoacoustic engine as an output is to generate electricity using a generator such as a linear motor and convert the input work flow into an electrical output. Non-Patent Document 1 describes a thermoacoustic generator that generates electricity using a thermoacoustic engine.

[0006] As another method, when the fluid in the heat accumulator is forced to vibrate by inputting sound waves, a temperature difference occurs between both ends of the heat accumulator along the flow line direction due to the heat pump effect, and it is possible to extract heat that is higher or lower than room temperature (ambient temperature). In this way, the heat accumulator has a heat pump effect that uses the work flow as an energy source, and can be used for "cooling" or "heating". For example, Non-Patent Document 2 describes a thermoacoustic refrigerator that performs "cooling" by using a work flow generated and amplified by a thermoacoustic engine.

[0007] These thermoacoustic coolers and generators are called thermoacoustic devices. Because the thermoacoustic engine used as the "prime mover" of a thermoacoustic device is an external combustion engine, research and development is currently being conducted on it as a waste heat recovery device. In the following, the unit consisting of a room temperature heat exchanger, heat storage unit, and high temperature heat exchanger will be referred to as the "prime mover," and the unit consisting of a room temperature heat exchanger, heat storage unit, and low temperature heat exchanger will be referred to as the "cooler." In order to expand the usable temperature range of the waste heat, it is desirable for a thermoacoustic device to operate with a small temperature gradient in the prime mover.

[0008] A method of multi-stage prime movers is known to operate a thermoacoustic engine with a small temperature difference. Hasegawa et al. developed a thermoacoustic cooler that operates with three prime movers, and reported that the cooler temperature is -107.4°C when the temperature of each prime mover is 270°C (Non-Patent Document 3).

[0009] Research and development of the above-mentioned thermoacoustic device as a waste heat recovery device is underway, but many current prime movers operate in a heat input temperature range of 200°C or higher. Meanwhile, a NEDO survey has reported that the temperature range of unused exhaust gas is often below 200°C, and that the need for unused waste heat is also often below 200°C (Non-Patent Document 4). [Prior art documents] [Patent documents]

[0010] [Patent Document 1] JP 2017-184457 A [Non-patent literature]

[0011] [Non-Patent Document 1] S. Backhaus, E. Tward, M. Petach, “Traveling-wave thermoacoustic electric generator”, Appl. Phys. Lett., 85, (2004) 1085-1087 [Non-Patent Document 2] T. Yazaki, T. Biwa, A. Tominaga, “A pistonless Stirling cooler”, Appl. Phys. Lett., 80 (2002) 157-159 [Non-Patent Document 3] EM Sharify, S. Hasegawa, “Traveling-wave thermoacousticrefrigerator driven by a multistage traveling-wave thermoacoustic engine”, Appl. Therm. Eng., 113 (2017), pp.791-795 [Non-Patent Document 4] Research Association for Innovative Thermal Energy Utilization Technology Development Center, "Report on the Survey of Waste Heat in the Industrial Sector," March 2019 Summary of the Invention [Problem to be solved by the invention]

[0012] In order to use thermoacoustic devices over a wide range of waste heat temperatures, it is necessary to expand the temperature range in which thermoacoustic coolers and generators can operate. Conventional technologies have made it possible to use them over a wide temperature range by designing them to operate at as low a temperature range as possible.

[0013] The operating temperature of a prime mover can be reduced by increasing the size of the device, pressurizing the working gas, or installing multiple prime movers in the device. Each method has the problem of increased manufacturing costs due to larger parts, pressure-resistant design, and an increased number of parts. In addition, when the operating conditions of a prime mover are high, it may be difficult to carry out prototypes and experiments during the development of the prime mover compared to when the operating conditions are atmospheric pressure.

[0014] The amplification factor of the work flow in a thermoacoustic prime mover depends heavily on the temperature ratio given to the prime mover. Therefore, a thermoacoustic cooler (heat pump) or a thermoacoustic generator that uses the work flow obtained by the prime mover depends on the performance of the prime mover. If you want to obtain a lower cooling temperature with a thermoacoustic cooler or increase the amount of power generated with a thermoacoustic generator, you need to increase the temperature ratio or use multiple prime movers to obtain a large amplification of the work flow in the thermoacoustic prime mover. Increasing the temperature difference between the prime movers narrows the range of applicability because the temperature range of the usable waste heat becomes higher. In addition, if the number of prime movers is increased, there is a problem that the device becomes more complicated and the device costs increase.

[0015] In reality, waste heat is not always discharged at a constant temperature, but fluctuates depending on the operating conditions of the machine that is the waste heat source. Therefore, when waste heat is used as a heat source for a prime mover, the output also fluctuates with the fluctuation in the waste heat temperature. For example, fluctuations in the waste heat temperature change the temperature ratio given to the prime mover, which in turn changes the work flow amplification factor of the prime mover. This changes the work flow input to the cooling machine and the generator, making it difficult to stably obtain the cooling temperature ratio of the cooling machine and the amount of power generated by the generator.

[0016] In addition, as the temperature ratio applied to the thermoacoustic prime mover changes, the sound field (frequency, phase, impedance, vibration amplitude, pressure amplitude, flow velocity amplitude) of the entire thermoacoustic system also changes. This causes a deviation from the sound field suitable for obtaining the desired output in the output side cooler or generator, causing the overall performance to fluctuate. This poses the problem that it becomes difficult to stably obtain the cooling temperature ratio in the cooler and the power generation amount in the generator.

[0017] In a thermoacoustic cooler, the magnitude of the work of the sound waves input to the cooler and the sound field in the system change depending on the temperature ratio in the heat storage unit of the prime mover, so the temperature ratio formed in the cooler fluctuates. Even when a thermoacoustic prime mover is combined with a generator, the magnitude of the work flow of the sound waves input to the generator and the sound field at the generator connection part fluctuate depending on the temperature ratio in the heat storage unit of the prime mover, so the amount of power generated by the generator depends on the temperature ratio given to the heat storage unit.

[0018] In this regard, Patent Document 1 describes a thermoacoustic generator that adjusts output in response to temperature changes in a heat source of a prime mover. This thermoacoustic generator includes a conduit, a prime mover, an output unit that outputs the work flow output from the prime mover as electric power, an adjustment unit that changes the length of the conduit, a detection unit that detects the temperature of the heat source, and a control unit that controls the adjustment unit based on the temperature detected by the detection unit to adjust the output of the output unit.

[0019] With this thermoacoustic generator, even if the temperature of the heat source changes, the adjustment unit with the bellows can mechanically change the length of the duct to adjust the output of the output unit. However, providing a mechanism for adjusting the bellows while using high-pressure gas also increases manufacturing costs. Furthermore, when manufacturing air conditioners using waste heat from automobiles and other devices that generate large vibrations during use, it is desirable to design them with as few mechanical parts as possible to reduce breakdowns.

[0020] The present invention has been made in consideration of the above circumstances, and aims to provide a control method for a thermoacoustic system that can obtain a desired output even if a temperature fluctuation occurs in a heat source with a simple configuration. Note that the contents of the present invention hereinafter will be described using a thermoacoustic heat pump as an example, but the control method can also be applied to a thermoacoustic generator or other thermoacoustic systems, and is not limited thereto. [Means for solving the problem]

[0021] One aspect of the present invention is a thermoacoustic system that utilizes an oscillatory flow proceeding through a pipe having a fixed pipe length, and includes at least one or more motive thermoacoustic devices that generate and amplify the work flow in the pipe by supplying heat, an output unit that inputs the work flow generated and amplified by the thermoacoustic device and extracts an output, an adjustment unit that is connected to the pipe and adjusts at least one of the work flow and the sound field of the oscillatory flow, a first detection unit that detects changes in parameters in the thermoacoustic device, a control unit, and a second detection unit that detects an output value of the output unit, wherein the adjustment unit has a drive unit that provides the oscillatory flow within the pipe, and the control unit controls the adjustment unit based on a first output value of the first detection unit and a second output value of the second detection unit to adjust the output of the output unit to a set value.

[0022] According to the present invention, the adjustment unit is configured to increase or decrease the work flow or adjust the sound field in the pipeline, and the output from the output unit can be adjusted as desired by controlling the adjustment unit to adjust the work flow or sound field in the pipeline in accordance with changes in the amount of heat supplied to the thermoacoustic device.

[0023] In the present invention, the first detection unit may be configured to detect at least one of the following parameters: temperature of a prime mover for driving a vehicle, temperature of a cooling machine, work flow output from the prime mover, frequency excited in the pipeline, phase in the pipeline, impedance in the pipeline, vibration amplitude in the pipeline, pressure amplitude in the pipeline, and flow velocity amplitude in the pipeline.

[0024] According to the present invention, even if a difference occurs in at least one of the detected parameters compared to an arbitrary set value due to a change in the amount of heat supplied, the adjustment unit can be controlled to increase or decrease the work flow in the tube or to set the sound field to an arbitrary set value, so that the work flow and / or the sound field input to the output unit can be adjusted to the desired value.

[0025] The present invention may also be configured such that, when the first output value is equal to or greater than a reference value, the control unit controls the adjustment unit to reduce the work flow and reduce the output output from the output unit.

[0026] According to the present invention, even if the amount of heat supplied increases and the output of the output section exceeds the set value, the adjustment section can be controlled to reduce the work flow in the pipeline, thereby reducing the work flow of the oscillating flow input to the output section and reducing the output from the output section.

[0027] The present invention may also be configured such that, when the first output value is less than a reference value, the control unit controls the adjustment unit to increase the work flow and increase the output from the output unit.

[0028] According to the present invention, even if the amount of heat supplied decreases and the output of the output section falls below the set value, the adjustment section can be controlled to increase the work flow in the pipeline, thereby increasing the work flow of the oscillating flow input to the output section and increasing the output from the output section.

[0029] The present invention may also be configured such that, when a sound field among the parameters detected by the first detection unit has a difference compared to a reference, the control unit controls the adjustment unit to adjust the sound field to the reference.

[0030] According to the present invention, even if the sound field at the output section deviates from the standard due to fluctuations in the amount of heat supplied, causing the output of the output section to differ from the desired value, the adjustment section can be controlled to adjust the sound field in the pipeline to an arbitrary value, so that the output from the output section can be set to the desired value by setting the sound field of the oscillating flow input to the output section to an arbitrary value.

[0031] The present invention may also be configured to include a second detection unit that detects an output value of the output unit, and to control the adjustment unit based on the first output value and a second output value of the second detection unit to adjust the output of the output unit to a set value.

[0032] According to the present invention, by monitoring the first output value and the second output value of the second detection unit, the work flow output from the adjustment unit and the work flow input to the adjustment unit can be adjusted, and the output of the output unit can be actively adjusted to a predetermined set value.

[0033] In the present invention, the adjustment unit may include a linear motor, and the control unit may be configured to input the work flow to the linear motor to generate power and reduce the work flow.

[0034] According to the present invention, by providing the adjustment unit with a linear motor and operating the linear motor as a generator, the work flow in the pipeline can be reduced, and the output of the output unit can be adjusted so that it does not exceed the set value.

[0035] In the present invention, the adjustment unit may include a linear motor, and the control unit may be configured to cause the linear motor to output another work flow to increase the work flow.

[0036] According to the present invention, since the adjustment unit is equipped with a linear motor, the linear motor can be operated to provide a work flow within the pipeline, thereby increasing the work flow within the pipeline, and the output of the output unit can be adjusted so that it does not fall below a set value.

[0037] In the present invention, the output section may also include another thermoacoustic device and be configured to output cold heat based on the work flow.

[0038] According to the present invention, by configuring the output section as a thermoacoustic device, it is possible to realize a heat pump such as a chiller or cooler that generates cold heat from the work flow input by the thermoacoustic phenomenon and has stabilized operation.

[0039] In the present invention, the output section may include a pulse tube refrigerator and may be configured to output cold heat based on the work flow.

[0040] According to the present invention, by configuring the output section as a pulse tube refrigerator, it is possible to realize a heat pump such as a chiller or cooler that generates cold heat from an input work flow and has stable operation.

[0041] In the present invention, the output section may include a generator, and may be configured to generate electricity based on the work flow.

[0042] According to the present invention, by configuring the output section as a generator, it is possible to realize a generator that outputs a constant electric power.

[0043] The present invention may also be configured so that the pipeline includes a straight pipe section formed in a straight pipe shape, and a first loop pipe formed in a loop shape provided at one end of the straight pipe section.

[0044] According to the present invention, a thermoacoustic system can be realized that includes a duct in which a loop tube is formed.

[0045] In the present invention, the pipeline may further include a second loop pipe formed in a loop shape and provided at the other end of the straight pipe portion.

[0046] According to the present invention, a thermoacoustic system having a double-loop pipe can be realized.

[0047] The present invention may also be configured such that the pipeline is formed in a loop shape.

[0048] According to the present invention, a thermoacoustic system can be realized even in a pipe formed in a loop shape.

[0049] One aspect of the present invention is a control method for a thermoacoustic system that utilizes an oscillatory flow proceeding through a conduit having a fixed conduit length, the control method comprising: supplying heat to at least one or more motive thermoacoustic devices that generate and amplify the work flow in the conduit; inputting the work flow generated and amplified by the thermoacoustic device to an output unit and outputting it from the output unit; detecting the temperature and sound field of the thermoacoustic device as a first output value; detecting the output value of the output unit as a second output value; an adjustment unit connected to the conduit has a drive unit, and driving the drive unit to provide the oscillatory flow in the conduit to adjust at least one of the work flow and the sound field in the conduit; and controlling the adjustment unit based on the first output value and the second output value to adjust at least one of the work flow and the sound field of the oscillatory flow and adjust the output to a set value.

[0050] According to the present invention, the output from the output unit can be arbitrarily adjusted by controlling the adjustment unit in response to changes in the amount of heat supplied to the thermoacoustic device and adjusting the work flow and sound field in the pipe. Effect of the Invention

[0051] According to the present invention, it is possible to realize a thermoacoustic system and a method for controlling a thermoacoustic system that can obtain a desired output even if a temperature fluctuation occurs in a heat source. [Brief description of the drawings]

[0052] [Figure 1] 1 is a diagram showing a configuration of a thermoacoustic system according to an embodiment of the present invention. [Diagram 2] 4 is a conceptual diagram showing the state of a working fluid at a branch point provided in a pipeline. FIG. [Diagram 3] FIG. 1 is a block diagram showing a configuration of a thermoacoustic system. [Figure 4] FIG. 1 is a diagram showing a configuration of a thermoacoustic system according to a first modified example. [Diagram 5] FIG. 11 is a diagram showing the configuration of a thermoacoustic system according to Modification 2. [Figure 6] FIG. 11 is a diagram showing the configuration of a thermoacoustic system according to Modification 3. [Figure 7] FIG. 11 is a diagram showing the configuration of a thermoacoustic system according to Modification 4. [Figure 8] FIG. 13 is a diagram showing the configuration of a thermoacoustic system according to Modification 5. [Figure 9] FIG. 13 is a diagram showing the configuration of a thermoacoustic system according to Modification 6. [Figure 10] FIG. 13 is a diagram showing the configuration of a thermoacoustic system according to Modification 7. [Figure 11] FIG. 13 is a diagram showing the configuration of a thermoacoustic system according to Modification 8. [Figure 12] FIG. 13 is a diagram showing the configuration of a thermoacoustic system according to a ninth modified example. [Figure 13] FIG. 23 is a diagram showing the configuration of a thermoacoustic system according to a tenth modification. [Figure 14] FIG. 15 is a diagram showing the configuration of a thermoacoustic system according to an eleventh modification. [Figure 15] FIG. 15 is a diagram showing the configuration of a thermoacoustic system according to a twelfth modification. [Figure 16] FIG. 23 is a diagram showing the configuration of a thermoacoustic system according to a thirteenth modification. [Figure 17] FIG. 21 is a diagram showing the configuration of a thermoacoustic system according to a fourteenth modification. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0053] Hereinafter, an embodiment of a thermoacoustic system and a control method for a thermoacoustic system according to the present invention will be described with reference to the drawings. The thermoacoustic system is a thermoacoustic system that uses an oscillatory flow that progresses inside a pipe having a fixed pipe length.

[0054] 1, the thermoacoustic system 1 includes a conduit P (flow path) in which a working gas is sealed, a first thermoacoustic device 2 connected to the conduit P, a second thermoacoustic device 6 (output unit) connected to the first thermoacoustic device 2 via the conduit P, and an adjustment unit 10 connected to the conduit P. The thermoacoustic system 1 is configured as, for example, a cooling machine.

[0055] The pipe P is formed with a fixed pipe length. The pipe P is, for example, a waveguide formed in a circular pipe shape with a circular cross section. The pipe P is formed so that the oscillating flow propagates in the pipe axis direction. The pipe P may have any shape as long as it is tubular, and may have, for example, a square or triangular cross section. The working fluid sealed in the pipe P is a gas capable of transmitting an oscillating flow, such as nitrogen, helium, argon, an inert gas consisting of a mixture of helium and argon, and air. The working fluid may be any gas capable of transmitting an oscillating flow, and may be any gas other than these gases, and may have a liquid portion such as water or ethanol, not limited to a gas.

[0056] The pipeline P includes a first loop pipe P1 and a second loop pipe P2 formed in a loop shape, a straight pipe section P3 formed in a straight pipe shape connecting the first loop pipe P1 and the second loop pipe P2, and a branch pipe P4 formed by branching off from the straight pipe section P3 and the first loop pipe P1.

[0057] A first loop pipe P1 is connected to one end of the straight pipe section P3. A second loop pipe P2 is connected to the other end of the straight pipe section P3. A branch pipe P4 branched into a T-shape is connected to one end of the straight pipe section P3. A first thermoacoustic device 2 that generates a work flow from a heat flow is provided in the flow path of the first loop pipe P1.

[0058] The first thermoacoustic device 2 includes a heat storage device 3 that generates and amplifies a work flow by generating a thermoacoustic phenomenon when a heat quantity is supplied, and a first heat exchanger 3C and a second heat exchanger 3D that perform heat exchange. Note that the first thermoacoustic device 2 may be a motive thermoacoustic device that utilizes an oscillatory flow, for example, a standing wave type oscillatory flow, a traveling wave type oscillatory flow, a phase change type oscillatory flow, or the like.

[0059] The heat accumulator 3 generates and amplifies a work flow when a temperature difference occurs between one end 3A on the upstream side and the other end 3B on the downstream side along the flow direction of the working gas. A first heat exchanger 3C is provided at one end 3A of the heat accumulator 3. A second heat exchanger 3D is provided at the other end 3B of the heat accumulator 3.

[0060] In the heat accumulator 3, a temperature gradient is generated along the axial direction of the pipe P at both ends by using the first heat exchanger 3C and the second heat exchanger 3D. When a temperature gradient (temperature difference) is formed between both ends of the heat accumulator 3 along the axial direction of the pipe P, work flow (acoustic power) is generated and amplified. When a sufficient temperature gradient is created at both ends of the heat accumulator 3 by the first heat exchanger 3C on the high temperature side and the second heat exchanger 3D on the low temperature side, sound waves are generated in the flow path 3R due to the phenomenon of thermoacoustic self-oscillation. The minimum temperature ratio at which self-oscillation occurs (high temperature side temperature T H / low temperature side T C ) is called the critical temperature ratio.

[0061] The heat accumulator 3 has, for example, one or more small-diameter flow passages 3R formed therein. One or an infinite number of flow passages 3R are provided so as to open along the flow line direction of the working gas in the heat accumulator 3. The heat accumulator 3 has, for example, a honeycomb structure formed of ceramics, or a structure in which a large number of stainless steel mesh thin plates are laminated, forming a large number of flow passages 3R. The heat accumulator 3 may be made of any material, such as a glass pipe, that forms fine flow passages and through which the oscillating flow can pass, and is not limited to these.

[0062] In addition, the flow path 3R may be formed by a shape formed from foamed metal or steel wool, or by filling it with metal powder, rolling up an uneven film, or combining thin plates with different flow path diameters (flow path widths), flow path shapes, and thicknesses.

[0063] The flow path 3R is formed, for example, in a cross section having a circular tube shape, a parallel plate shape, a polygonal shape, or a pin array shape. The flow path 3R may be formed to have a plurality of randomly shaped flow paths by combining thin plates having different flow path diameters (flow path widths), flow path shapes, and thicknesses. The flow path 3R may be formed by repeating flow paths of a plurality of patterns by a predetermined combination of thin plates having different flow path diameters (flow path widths), flow path shapes, and thicknesses. To generate a temperature gradient in the heat storage device 3, heat is input from a heat source.

[0064] The heat source supplies a heat quantity having a temperature difference with respect to the room temperature as the ambient temperature. Here, the room temperature is, for example, a temperature that can be obtained stably from the surrounding environment such as the atmosphere, seawater, river water, lake water, and geothermal heat. The room temperature may be a temperature generated from another heat source that can stably supply heat quantity so as to generate a temperature difference with the heat source other than the ambient temperature. The heat source utilizes, for example, unused heat quantity discarded as waste heat. The heat source provides a heat quantity that is high in temperature with respect to the room temperature. The heat source is not particularly limited as long as it can obtain heat quantity, and for example, heat quantity obtained from sunlight, geothermal heat, etc., or heat quantity generated from engines, factories, various facilities, etc., is used. The heat quantity is, for example, input to the first heat exchanger 3C.

[0065] The first heat exchanger 3C is formed to perform heat exchange via a heat medium at one end 3A of the heat accumulator 3. The first heat exchanger 3C exchanges heat with the one end 3A of the heat accumulator 3 via a heat medium having a temperature difference with respect to room temperature.

[0066] The second heat exchanger 3D is formed to perform heat exchange at the other end 3B of the heat accumulator 3. The second heat exchanger 3D exchanges heat with the other end 3B of the heat accumulator 3 via a room temperature heat medium. As a method of inputting heat, for example, a high temperature heat is supplied to one end 3A side of the heat accumulator 3 by the first heat exchanger 3C. For example, a heat medium such as a high temperature gas or liquid is circulated in the first heat exchanger 3C. On the other hand, for example, a room temperature heat is supplied to the other end 3B side of the heat accumulator 3 by the second heat exchanger 3D. For example, a heat medium such as a room temperature gas or liquid is circulated in the second heat exchanger 3D.

[0067] In this case, a temperature gradient is generated from one end 3A of the heat storage device 3, which is the high temperature side, to the other end 3B of the heat storage device 3, which is the room temperature side, and a work flow is generated and amplified. When a temperature gradient (temperature difference) is generated between one end 3A and the other end 3B of the heat storage device 3 by the above method, a work flow of the working gas is generated and amplified in the heat storage device 3, and propagates through the pipe P. Work can be extracted from the work flow propagating through the pipe P. The extracted output may be used as it is to drive a turbine or the like, or may be converted into another output such as a cold source, a hot source, or electricity. There is no particular limit to the method of using the output extracted from the work flow. For example, a second thermoacoustic device 6 for operation (another thermoacoustic device) having a heat storage device different from the first thermoacoustic device 2 in the pipe P can be used. With the thermoacoustic device for operation, the work of the input oscillating flow can be converted into heat (heat pump effect) and extracted.

[0068] At this time, a heat pump effect is produced in the heat storage unit of the second thermoacoustic device 6 for operation so as to generate a temperature gradient in the opposite direction along the gas flow line direction in the first thermoacoustic device 2 for operation, so that heat can be extracted from the input work flow by utilizing the thermoacoustic phenomenon.

[0069] The second thermoacoustic device 6 for actuation will be described below. The same names are used for the same components as the first thermoacoustic device 2 for motive power, and duplicated descriptions will be omitted as appropriate. The second thermoacoustic device 6 for actuation is configured as an output section that receives the work flow generated by the first thermoacoustic device 2 for motive power and extracts the output.

[0070] The second thermoacoustic device 6 for operation includes a heat accumulator 7 (second heat accumulator) provided in the second loop pipe P2, a third heat exchanger 7C provided at one end 7A of the heat accumulator 7, and a fourth heat exchanger 7D provided at the other end 7B of the heat accumulator 7. The second thermoacoustic device 6 for operation is configured as, for example, a cooler or a refrigerator that extracts cold heat. The heat accumulator 7 may be called a cold accumulator.

[0071] To the heat accumulator 7, for example, the work flow generated from the first thermoacoustic device 2 for driving is input from one end portion 7A on the upstream side.

[0072] The third heat exchanger 7C is formed to perform heat exchange at one end 7A of the heat accumulator 7. The third heat exchanger 7C cools the one end 7A of the heat accumulator 7. The third heat exchanger 7C circulates a heat medium and performs heat exchange at the one end 7A.

[0073] The fourth heat exchanger 7D is formed to perform heat exchange at the other end 7B of the heat accumulator 7. The fourth heat exchanger 7D extracts cold heat from the other end 7B of the heat accumulator 7, for example. The fourth heat exchanger 7D circulates a heat medium and performs heat exchange at the other end 7B.

[0074] For example, when a work flow generated by energy conversion from the first thermoacoustic device 2 for driving is input to one end 7A of the heat storage device 7, a heat pump effect occurs and a temperature difference occurs in the flow path axial direction of the heat storage device. At this time, when the one end 7A side is heat exchanged with a room temperature heat medium by the third heat exchanger 7C, a temperature difference occurs based on the one end 7A side, and an endothermic reaction occurs at the other end 7B side. At this time, when heat exchange is performed by the fourth heat exchanger 7D on the other end 7B side, a low-temperature heat quantity can be extracted. This reaction can be used to configure a cooling machine, a cooler, etc. The second thermoacoustic device 6 may be changed to a generator or a heating machine depending on the purpose of the system to be configured.

[0075] Next, the adjustment unit 10 will be described. The adjustment unit 10 is configured to adjust both or either one of the work flow and the sound field of the oscillating flow in the pipe P. Below, a case where the adjustment unit 10 adjusts the sound field in the pipe P will be described. The adjustment unit 10 is actively controlled in response to a change in the temperature ratio of the heat accumulator 3 of the first thermoacoustic device 2 for driving, and adjusts the temperature ratio in the second thermoacoustic device 6 for operation to a set value. The adjustment unit 10 is configured, for example, by a linear motor. The adjustment unit 10 is controlled by a control unit 12 described later.

[0076] The adjustment unit 10 includes a piston 10A that reciprocates within the branch pipe P4, a piston rod 10B connected to the piston, a drive unit 10C that drives the piston rod 10B, and a power source 10D. The piston rod 10B is made of a magnetic material. The drive unit 10C has an electromagnetic coil, and generates an AC magnetic field when an AC current is input from the power source 10D. The piston rod 10B is attached so as to be able to slide freely through the center of the electromagnetic coil. When an AC magnetic field is generated in the electromagnetic coil, the piston rod 10B reciprocates relative to the electromagnetic coil.

[0077] The adjustment unit 10 drives the drive unit 10C to reciprocate the piston rod 10B, thereby reciprocating the piston 10A in the branch pipe P4 in conjunction with the drive unit 10, and provides an oscillatory flow in the pipe P. The adjustment unit 10 can generate a work flow in the same frequency band as the work flow input to the second thermoacoustic device 6, for example, and increase the work flow of the oscillatory flow in the pipe P.

[0078] The adjustment unit 10 may be used as a generator. In the adjustment unit 10, a work flow is input from the branch pipe P4, and the piston 10A reciprocates in the branch pipe P4. The piston rod 10B reciprocates in conjunction with the movement of the piston 10A, generating an AC magnetic field and causing an AC current to flow in the electromagnetic coil. The adjustment unit 10 can generate power based on the work flow generated and amplified by the first thermoacoustic device 2, for example, and reduce the work flow of the oscillatory flow in the pipe P. The adjustment unit 10 is not limited to the above configuration as long as it can adjust the sound field and the oscillatory flow, and may have an increased or decreased number of parts or a changed configuration, and is not limited thereto. In addition, the adjustment unit 10 may use a device other than a linear motor as long as it can adjust the work flow of the oscillatory flow in the pipe P.

[0079] As shown in FIG. 2, it is possible to divide the flow velocity amplitude of the working fluid in the branch pipe P4 of the pipe P. In this case, the pressure amplitude of the working fluid in the branch pipe P4 does not change (P engine =P Ref =P linearThe sum of the flow velocity amplitudes of the working fluid is preserved in the branch pipe P4. The ratio at which the flow velocity amplitudes of the working fluid are divided is determined by the impedance Z of the second thermoacoustic device 6 and the adjustment unit 10 connected to the pipe P.

[0080] The vibration amplitude of the adjustment unit 10 can be controlled by the voltage input from the power source 10D. When the temperature of the heat source changes, the work flow output from the first thermoacoustic device 2 for driving changes. In this case, the voltage input to the adjustment unit 10 is adjusted to adjust the work flow flowing to the second thermoacoustic device 6 for operation or the sound field of the pipe to a constant value. This adjustment makes it possible to keep the temperature ratio between the one end 7A side and the other end 7B side of the heat storage unit 7 of the second thermoacoustic device 6 constant. Therefore, the adjustment unit 10 can output the work flow from inside the pipe P and input the work flow into the pipe P.

[0081] Next, a description will be given of the control of the thermoacoustic system 1. Hereinafter, the description of the same configuration as that described above will be omitted as appropriate.

[0082] As shown in Figure 3, the thermoacoustic system 1 includes a first thermoacoustic device 2 for driving, a first detection unit 4 for detecting the temperature of the first thermoacoustic device 2, an output unit 6 for operation, a second detection unit 8 for detecting the output value of the output unit 6, an adjustment unit 10 connected to a pipeline P, and a control unit 12 for controlling the operation of the adjustment unit 10.

[0083] The first detector 4 detects, for example, a temperature T H and the temperature T of the other end 3B, which is lower C The first output value detected by the first detector 4 is output to the controller 12. The second detector 8 detects, for example, the temperature T A and the temperature T Ref The second output value detected by the second detection unit 8 is output to the control unit 12.

[0084] The control unit 12 calculates the temperature ratio (TH / T C The control unit 12 calculates the temperature ratio (T A / T Ref ) is calculated.

[0085] For example, based on the calculation results of the temperature ratio in the heat accumulator 3 and the temperature ratio in the heat accumulator 7, when the temperature of the heat source is high and the temperature ratio in the heat accumulator 3 of the first thermoacoustic device 2 is equal to or higher than the critical temperature ratio, the control unit 12 stops the power supply 10D of the adjustment unit 10, applies a load, and operates the adjustment unit 10 as a generator. The control unit 12 reduces the work flow of the work flow in the pipe P by causing the adjustment unit 10 to generate power, and maintains the temperature ratio in the heat accumulator 7 of the second thermoacoustic device 6 constant so as to be equal to the set value. That is, when the first output value is equal to or higher than the reference value, the control unit 12 controls the adjustment unit 10 to generate power, and reduces the work flow to reduce the output from the second thermoacoustic device 6 (output unit).

[0086] For example, based on the calculation results of the temperature ratio in the heat accumulator 3 and the temperature ratio in the heat accumulator 7, when the temperature of the heat source is low and the temperature ratio in the heat accumulator 3 of the first thermoacoustic device 2 is less than the critical temperature ratio, the control unit 12 inputs power from the power source 10D to the adjustment unit 10 to operate the adjustment unit 10 and increase the work flow in the pipe P. By increasing the work flow in the pipe from the adjustment unit 10, the control unit 12 maintains the temperature ratio in the heat accumulator 7 of the second thermoacoustic device 6 constant so as to be the set value. In other words, when the first output value is less than the reference, the control unit 12 controls the adjustment unit 10 to output another work flow, and increases the work flow to increase the output from the second thermoacoustic device 6.

[0087] For example, based on the calculation results of the temperature ratio in the heat accumulator 3 and the temperature ratio in the heat accumulator 7, when the sound field formed in the first thermoacoustic device 2 differs from a set value due to a change in the heat source temperature, the control unit 12 inputs power from the power source 10D to the adjustment unit 10 to operate the adjustment unit 10 and adjusts the work flow and the sound field in the conduit P. For example, when the sound field among the parameters detected by the first detection unit 4 has a difference compared to a reference, the control unit 12 controls the adjustment unit 10 to adjust the sound field to the reference. The control unit 12 maintains the temperature ratio in the heat accumulator 7 of the second thermoacoustic device 6 constant so as to be a set value by having the adjustment unit 10 adjust the sound field in the conduit.

[0088] As described above, according to the thermoacoustic system 1, even if the temperature of the heat source of the first thermoacoustic device 2 for driving, which utilizes waste heat or the like, changes, the adjustment unit 10 is controlled to decrease or increase the work flow of the oscillating flow in the pipe P, thereby realizing a heat pump that adjusts the output of the second thermoacoustic device 6 for operation to a set value. According to the thermoacoustic system 1, even if the temperature of the heat source of the first thermoacoustic device 2 for driving increases and the output of the second thermoacoustic device 6 for operation increases, the linear motor of the adjustment unit 10 is used as a generator to decrease the work flow in the pipe P and lower the output of the second thermoacoustic device 6 for operation, thereby adjusting it to a predetermined set value.

[0089] According to the thermoacoustic system 1, even if the temperature of the heat source of the first motive thermoacoustic device 2 becomes low and the output of the second operating thermoacoustic device 6 decreases, the linear motor of the adjustment unit 10 is driven to provide a work flow within the pipeline P, thereby increasing the output of the second operating thermoacoustic device 6 and adjusting it to a predetermined set value.

[0090] Up to this point, we have explained a control method based on the calculation results of the temperature ratio in the heat storage device 3 and the temperature ratio in the heat storage device 7. However, the adjustment unit 10 may have the control unit 12 reduce or amplify the work flow of the oscillating flow in the pipeline P based on changes in the sound field generated from the first thermoacoustic device 2, or the first detection unit may detect the output of the output unit 6, and the control unit 12 may reduce or amplify the work flow of the oscillating flow in the pipeline P based on the output value.

[0091] Further, up to this point, the control method has been described in the embodiment having a detection unit outside the control unit 12 or the adjustment unit 10, but the detection unit does not necessarily have to be provided outside the control unit or the adjustment unit, and the control unit 12 or the adjustment unit 10 may also function as the detection unit. Further, each of the detection units, the first detection unit 4 and the second detection unit 8, detects temperature, but is not limited to this and may detect various parameters other than temperature.

[0092] Each of the first detection unit 4 and the second detection unit 8 may detect at least one of the following parameters: the temperature of the prime mover for driving the engine, the temperature of the cooling machine, the work flow output from the prime mover, the frequency excited in the pipeline P, the phase in the pipeline P, the impedance in the pipeline P, the vibration amplitude in the pipeline P, the pressure amplitude in the pipeline P, and the flow velocity amplitude in the pipeline P. The control unit 12 may adjust the adjustment unit 10 in accordance with the detection values ​​of the various parameters detected by the detection units, and adjust the output value of the output unit.

[0093] Furthermore, the control method may be to control the work flow of the oscillating flow in the pipe P and the change in the sound field by iterating the detection by the detector and the adjustment by the controller 12 and the adjuster 10, or to control by storing in a database the adjustment values ​​for the change parameters required to set arbitrary values ​​according to the parameter changes. The thermoacoustic system 1 may include a storage unit (not shown) that stores the databased adjustment values, and the adjustment values ​​may be provided to the controller 12 from a server device (not shown) connected to the network. The controller 12 may also be provided in a terminal device connected to the network. That is, the thermoacoustic system 1 may be remotely operated from the network.

[0094] In the following, modified examples of the thermoacoustic system will be described. In the following description, the same components as those in the above embodiment will be designated by the same names and reference numerals, and duplicated descriptions will be omitted as appropriate.

[0095] [Variation 1] In the above embodiment, the output section of the thermoacoustic system 1 is configured as a cooling machine or a cooler using the second thermoacoustic device 6. The output section of the thermoacoustic system may be replaced with another cooling machine.

[0096] 4, the thermoacoustic system 1A is configured by replacing the output unit with a pulse tube refrigerator 20. The output unit includes the pulse tube refrigerator 20 and is configured to output cold heat based on a work flow. The temperature ratio of the pulse tube refrigerator 20 is monitored by the control unit 12 as a second output value.

[0097] The pulse tube refrigerator 20 includes a heat accumulator 21 (cool accumulator) having one end 21A connected to the other end of the straight tube section P3, a pulse tube 22 having one end 22A connected to the other end 21B of the heat accumulator 21, a capillary tube 23 having one end 23A connected to the other end 22B of the pulse tube 22, and a tank 24 connected to the other end 23B of the capillary tube 23. Vibrations of the working fluid are input to the one end 21A of the heat accumulator 21. The gas inside the heat accumulator 21 repeatedly compresses and expands in response to the vibrations.

[0098] In the pulse tube 22, the gas reciprocates like a piston in response to the vibration input to the heat accumulator 21. In the pulse tube 22, a cooling effect occurs on the other end 21B side where the gas expands, based on the phase difference between the pressure vibration and the displacement of the gas piston in the pulse tube 22.

[0099] The control unit 12 controls the adjustment unit 10 in accordance with an increase or decrease in the work flow supplied by the first thermoacoustic device 2 or a change in the sound field based on the first output value, thereby making it possible to keep the temperature ratio of the pulse tube refrigerator 20 constant.

[0100] [Variation 2] In the above embodiment, the output section of the thermoacoustic system 1 is configured as a cooling machine or a cooler using the second thermoacoustic device 6. The output section of the thermoacoustic system may be replaced with another configuration.

[0101] As shown in FIG. 5, the thermoacoustic system 1B is configured by replacing the output section with a generator 30. The generator 30 is provided at the other end of the straight pipe section P3. The generator 30 includes, for example, a linear motor. The generator 30 is configured to generate power based on the work flow in the pipe P. The generator 30 is connected to a load 30F. The power output from the load 30F by the control unit 12 is monitored as a second output value.

[0102] The generator 30 includes a piston 30A, a piston rod 30B, and an electromagnetic coil 30C. In the generator 30, the piston 30A vibrates along the pipe axis direction in response to the vibration of the oscillating flow proceeding through the pipe P. The piston rod 30B vibrates in conjunction with the vibration of the piston 30A. The vibration of the piston rod 30B is electromagnetically induced, and an alternating current flows in the electromagnetic coil 30C.

[0103] The control unit 12 controls the adjustment unit 10 in accordance with an increase or decrease in the work flow supplied by the first thermoacoustic device 2 based on the first output value or a change in the sound field, so as to cause the generator 30 to output a constant electric power.

[0104] [Variation 3] In the above embodiment, the adjustment unit 10 of the thermoacoustic system 1 is connected to the branch pipe P4 of the pipe P formed in a double loop. In the thermoacoustic system, the pipe P may be formed in a loop, and the adjustment unit 10 may be provided midway through the loop-shaped pipe P.

[0105] As shown in FIG. 6, in the thermoacoustic system 1C, the pipe P is formed in a loop shape. In the thermoacoustic system 1C, the first thermoacoustic device 2 and the second thermoacoustic device 6 are directly connected. The adjustment unit 40 is connected midway through the pipe P. The adjustment unit 40 includes a linear motor. The adjustment unit 40 includes a pair of pistons 40A, 40B, a piston rod 40C, a drive unit 40D, and a power source 40E. In the adjustment unit 40, the piston rod 40C slides along the pipe axis direction. A pair of pistons 40A, 40B are attached to both ends of the piston rod 40C.

[0106] The control unit 12 controls the adjustment unit 40 in accordance with an increase or decrease in the work flow supplied by the first thermoacoustic device 2 based on the first output value or a change in the sound field, thereby making it possible to keep the temperature ratio of the second thermoacoustic device 6 constant.

[0107] [Variation 4] 7, a thermoacoustic system 1D includes a loop-shaped pipe P, and the second thermoacoustic device 6 of the third modification is replaced with a pulse-tube refrigerator 20 connected to a branch pipe P5. The control unit 12 controls the adjustment unit 40 in response to an increase or decrease in the work flow supplied by the first thermoacoustic device 2 based on the first output value or a change in the sound field, thereby making it possible to keep the temperature ratio of the pulse-tube refrigerator 20 constant.

[0108] [Variation 5] 8, a thermoacoustic system 1E includes a loop-shaped pipe P, and a first thermoacoustic device 2 and a second thermoacoustic device 6 are connected to the pipe P. A branch pipe P6 is provided downstream of the first thermoacoustic device 2. An adjustment unit 10 is connected to the branch pipe P6.

[0109] The control unit 12 controls the adjustment unit 10 in accordance with an increase or decrease in the work flow supplied by the first thermoacoustic device 2 based on the first output value or a change in the sound field, thereby keeping the temperature ratio of the second thermoacoustic device 6 constant.

[0110] [Variation 6] 9, the thermoacoustic system 1F includes a straight pipe P, and a first thermoacoustic device 2 and a pulse tube refrigerator 20 are connected in the pipe P. An adjustment unit 10 is provided on the upstream side of the first thermoacoustic system 1F.

[0111] The control unit 12 controls the adjustment unit 10 in accordance with an increase or decrease in the work flow supplied by the first thermoacoustic device 2 or a change in the sound field based on the first output value, thereby making it possible to keep the temperature ratio of the pulse tube refrigerator 20 constant.

[0112] [Variation 7] 10, the thermoacoustic system 1G includes a straight pipe P and a second loop pipe P2. The pipe P is provided with a first thermoacoustic device 2 on the input side and a second thermoacoustic device 6 provided in the second loop pipe P2 on the output side. An adjustment unit 10 is provided upstream of the first thermoacoustic system 1G.

[0113] The control unit 12 controls the adjustment unit 10 in accordance with an increase or decrease in the work flow supplied by the first thermoacoustic device 2 based on the first output value or a change in the sound field, thereby keeping the temperature ratio of the second thermoacoustic device 6 constant.

[0114] [Variation 8] 11, a thermoacoustic system 1H includes a straight pipe P, and a first thermoacoustic device 2 is provided inside the pipe P. An adjustment unit 10 is provided on the upstream side of the first thermoacoustic system 1H. A generator 30 is provided on the downstream side of the pipe P (see FIG. 5).

[0115] The control unit 12 controls the adjustment unit 10 in response to an increase or decrease in the work flow supplied by the first thermoacoustic device 2 based on the first output value or a change in the sound field, thereby making it possible to keep the output value of the generator 30 constant.

[0116] [Variation 9] 12, the thermoacoustic system 1I includes a first thermoacoustic device 2, an adjustment unit 10, and a pulse tube refrigerator 20. A linear motor R is provided upstream of the first thermoacoustic system 1I as an input source of the oscillating flow. A branch pipe P7 is formed in the middle of the pipe P, and the adjustment unit 10 is connected to the branch pipe P7.

[0117] The control unit 12 controls the adjustment unit 10 in accordance with an increase or decrease in the work flow supplied by the first thermoacoustic device 2 or a change in the sound field based on the first output value, thereby making it possible to keep the temperature ratio of the pulse tube refrigerator 20 constant.

[0118] [Variation 10] 13, a thermoacoustic system 1J is configured by replacing the pulse tube refrigerator 20 of the 9th modification with a second thermoacoustic device 6 provided in a second loop tube P2. A linear motor R is provided upstream of the thermoacoustic system 1J as an input source of the oscillating flow. An adjustment unit 10 is provided midway through the pipe P via a branch pipe P7.

[0119] The control unit 12 controls the adjustment unit 10 in accordance with an increase or decrease in the work flow supplied by the first thermoacoustic device 2 based on the first output value or a change in the sound field, thereby keeping the temperature ratio of the second thermoacoustic device 6 constant.

[0120] [Variation 11] 14, a thermoacoustic system 1K is configured by replacing the pulse tube refrigerator 20 of the ninth modification with a generator 30. A linear motor R is provided upstream of the first thermoacoustic system 1K as an input source of the oscillating flow. An adjustment unit 10 is provided midway through the pipe P via a branch pipe P7.

[0121] The control unit 12 controls the adjustment unit 10 in response to an increase or decrease in the work flow supplied by the first thermoacoustic device 2 based on the first output value or a change in the sound field, thereby making it possible to keep the output of the linear generator constant.

[0122] [Variation 12] 15, a thermoacoustic system 1L includes a straight pipe P, and includes a first thermoacoustic device 2 on the upstream side and a pulse tube refrigerator 20 on the downstream side of the pipe P. An adjustment unit 10 is provided in the pipe P via a branch pipe P7.

[0123] The control unit 12 controls the adjustment unit 10 in accordance with an increase or decrease in the work flow supplied by the first thermoacoustic device 2 or a change in the sound field based on the first output value, thereby making it possible to keep the temperature ratio of the pulse tube refrigerator 20 constant.

[0124] [Variation 13] 16, a thermoacoustic system 1M includes a first thermoacoustic device 2 and a second thermoacoustic device 6 provided in a second loop pipe P2 in a straight pipe P. An adjustment unit 10 is provided in the pipe P via a branch pipe P7.

[0125] The control unit 12 controls the adjustment unit 10 in accordance with an increase or decrease in the work flow supplied by the first thermoacoustic device 2 based on the first output value or a change in the sound field, thereby keeping the temperature ratio of the second thermoacoustic device 6 constant.

[0126] [Variation 14] 17, a thermoacoustic system 1N includes a straight pipe P, a first thermoacoustic device 2 on the upstream side, and a generator 30 on the downstream side. An adjustment unit 10 is provided in the pipe P via a branch pipe P7.

[0127] The control unit 12 controls the adjustment unit 10 in response to an increase or decrease in the work flow supplied by the first thermoacoustic device 2 based on the first output value or a change in the sound field, thereby making it possible to keep the output of the generator 30 constant.

[0128] As described above, the thermoacoustic system according to the embodiment can be realized by various device configurations as long as the adjustment unit can be connected. In addition, the thermoacoustic system according to the embodiment can be applied regardless of the following parameters that exist as design elements. In addition, in the above-mentioned embodiment, the prime mover is installed in a loop tube or a straight tube, but this shape is not limited to this as long as the work flow can be amplified and generated, and the shapes, numbers, and combinations of the thermoacoustic prime mover, control unit, adjustment unit, detection unit, and output unit are not limited to the shapes of the embodiment. Furthermore, the generation of the oscillating flow itself may not be performed from the thermoacoustic prime mover, and there may be an input source for the oscillating flow. (1) Type of working gas and average pressure (2) Flow path diameter, length, and material of the heat accumulator (3) Pipe size, length, and shape (circular pipe, rectangular pipe) (4) Whether or not the cross-sectional area is enlarged at the location of the engine or cooler (5) Gradual expansion of the cross-sectional area of ​​the pipe (6) Number of prime movers in the thermoacoustic device (7) The number of outlets for work, such as coolers and generators, within the thermoacoustic device

[0129] As described above, the thermoacoustic phenomenon has been used as an example for explanation, however, the present invention is not limited to thermoacoustic engines based on the thermoacoustic phenomenon, and can be applied to energy conversion devices such as Stirling engines equipped with a heat storage device that utilizes an oscillating flow of fluid, pulse tube refrigerators, GM refrigerators, Stirling coolers, heat pipes, and thermoacoustic engines.

[0130] Although the above description has been given taking the work flow as an example of a control element, the present invention is applicable regardless of the following parameters that exist as control elements. (1) Frequency (2) Phase (3) Impedance (4) Vibration amplitude (5) Pressure amplitude (6) Flow velocity amplitude [Explanation of symbols]

[0131] 1 Thermoacoustic system, 1A-1M Thermoacoustic system, 2 First thermoacoustic device, 3 Heat storage, 3C First heat exchanger, 3D Second heat exchanger, 3R Flow path, 4 First detection section, 6 Second thermoacoustic device, 6 Output section, 7 Heat storage, 7C Third heat exchanger, 7D Fourth heat exchanger, 8 Second detection section, 10 Adjustment section, 10A Piston, 10B Piston rod, 10C Driving section, 10D Power supply, 12 Control section, 20 Pulse tube refrigerator, 21 Heat storage, 22 Pulse tube, 23 Capillary tube, 24 Tank, 30 Generator, 30A Piston, 30B Piston rod, 30C Electromagnetic coil, 30F Load, 40 Adjustment section, 40A Piston, 40B Piston, 40C Piston rod, 40D Driving section, 40E Power supply, P Pipe, P1 1st loop pipe, P2 2nd loop pipe, P3 straight pipe section, P4-P7 branch pipe, R linear motor

Claims

1. A thermoacoustic system utilizing an oscillatory flow that travels through a pipe having a fixed pipe length, At least one or more motive thermoacoustic devices that generate and amplify a work flow in the pipe by supplying a heat quantity; an output section that receives the work flow generated and amplified by the thermoacoustic device and outputs the work flow; an adjustment unit connected to the pipe for adjusting at least one of the work flow and the sound field of the vibration flow; A first detector for detecting a change in a parameter of the thermoacoustic device; A control unit; a second detection unit that detects an output value of the output unit, the adjustment unit has a drive unit that applies the oscillating flow to the inside of the pipeline, the control unit controls the adjustment unit based on a first output value of the first detection unit and a second output value of the second detection unit to adjust the output of the output unit to a set value. Thermoacoustic system.

2. The thermoacoustic system of claim 1, wherein the first detection unit detects at least one of the following parameters: temperature of a prime mover for driving the engine, temperature of a cooling machine, work flow output from the prime mover, frequency excited in the pipeline, phase in the pipeline, impedance in the pipeline, vibration amplitude in the pipeline, pressure amplitude in the pipeline, and flow velocity amplitude in the pipeline.

3. The control unit controls the adjustment unit to reduce the output from the output unit when the first output value is equal to or greater than a reference value.

3. A thermoacoustic system according to claim 1 or 2.

4. The control unit controls the adjustment unit to increase the output from the output unit when the first output value is less than a reference value.

3. A thermoacoustic system according to claim 1 or 2.

5. The thermoacoustic system according to claim 1 or 2, wherein when the sound field among the parameters detected by the first detection unit has a difference compared to a reference, the control unit controls the adjustment unit to adjust the sound field to the reference.

6. The adjustment unit is a linear motor. A thermoacoustic system according to any one of claims 1 to 5.

7. The adjustment unit includes a linear motor. The control unit is Reducing the vibration amplitude of the linear motor and reducing the work flow; Increasing the vibration amplitude of the linear motor to increase the work flow; A thermoacoustic system according to any one of claims 1 to 5.

8. The output unit includes another thermoacoustic device and is configured to output cold heat based on the work flow. A thermoacoustic system according to any one of claims 1 to 7.

9. The output unit includes a pulse tube refrigerator and is configured to output cold heat based on the work flow. A thermoacoustic system according to any one of claims 1 to 7.

10. The thermoacoustic system of claim 1 , wherein the output section comprises a generator and is configured to generate electricity based on the work flow.

11. The pipe includes a straight pipe portion formed in a straight pipe shape, The thermoacoustic system according to claim 1 , further comprising: a first loop tube formed in a loop shape and provided at one end of the straight tube portion.

12. The pipeline includes a second loop pipe formed in a loop shape and provided at the other end of the straight pipe portion.

12. A thermoacoustic system as described in claim 11.

13. The pipeline is formed in a loop shape. A thermoacoustic system according to any one of claims 1 to 10.

14. A method for controlling a thermoacoustic system using an oscillatory flow that travels through a pipe having a fixed pipe length, comprising: Supplying heat to at least one motive thermoacoustic device that generates and amplifies a work flow in the conduit; The work flow generated and amplified by the thermoacoustic device is input to an output section; Taking an output from the output section; Detecting a change in a parameter of the thermoacoustic device as a first output value; Detecting an output value of the output unit as a second output value; an adjustment unit connected to the pipeline includes a drive unit, and adjusts at least one of a work flow and a sound field in the pipeline by driving the drive unit to provide the oscillatory flow in the pipeline; Based on the first output value and the second output value, the adjustment unit is controlled to adjust at least one of the work flow of the vibration flow and the sound field, thereby adjusting the output to a set value. A method for controlling a thermoacoustic system.

Images