JP2016183844A - Thermoacoustic engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoacoustic engine capable of being miniaturized and improving energy conversion efficiency per a unit volume.SOLUTION: A thermoacoustic engine comprises a housing body C1 filled with a working medium, and a partitioning portion C2 partitioning the inside of the housing body into a circulation propagation path capable of propagating acoustic wave. The circulation propagation path includes at least one or more of motors 10a and 10b composed of heaters 11a and 11b for heating the working medium from the external, coolers 12a and 12b for cooling the working medium from the external, and regenerators 13a and 13b for amplifying the acoustic wave between the heaters 11a and 11b and the coolers 12a and 12b, and includes a power generator 40 generating electric power from vibration of the acoustic wave.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a thermoacoustic engine that converts heat energy held by heat media having different temperatures into vibration energy of sound waves.

Conventionally, as a thermoacoustic engine that converts heat energy held by heat media at different temperatures into vibration energy of sound waves, heating the working medium from the outside into a hollow cylindrical cylindrical tube filled with the working medium There is known a thermoacoustic engine including a motor, a cooler that cools a working medium from the outside, and a regenerator that amplifies sound waves between the heater and the cooler (Patent Document 1, 2).
In such a thermoacoustic engine, in a regenerator in which a temperature difference occurs between both ends, thermal energy is converted into acoustic vibration energy in a form in which acoustic vibration energy is amplified. Here, the length of the looped acoustic cylinder is determined based on the wavelength of the sound wave formed inside, but in order to increase the conversion efficiency from the thermal energy to the vibration energy of the sound wave, it is constant. It is known that it is preferable to set the length as described above (see Patent Document 3).
However, if the loop-shaped acoustic cylinder is provided with a certain length or more, a dead space (a space in which no acoustic cylinder is provided) is formed inside the loop, so that miniaturization becomes a problem.
Therefore, the thermoacoustic engines disclosed in Patent Documents 1 and 2 are configured such that the looped acoustic cylinder is wound a plurality of times in a coil shape, and the acoustic cylinders are arranged close to each other. The miniaturization is aimed at.

JP 2011-002118 A JP 2011-002119 A Japanese Patent No. 5616287

  In the techniques disclosed in Patent Documents 1 and 2 above, a looped acoustic cylinder is wound a plurality of times and each of the acoustic cylinders is disposed in proximity to each other. As shown in Fig. 1 of Fig. 2, the loop-shaped acoustic cylinder wound a plurality of times has a dead space (a space in which no acoustic cylinder is provided) formed in the vicinity of the winding axis. It is difficult to say that the size has been reduced, and there was room for improvement from the viewpoint of space saving. And in such a structure, since the energy conversion efficiency per unit volume falls by the part of dead space, the improvement was desired.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a thermoacoustic engine that can be made compact and space-saving and can improve energy conversion efficiency per unit volume.

The characteristic configuration of the thermoacoustic engine for achieving the above object is as follows:
A housing body filled with a working medium;
A partition that partitions the inside of the housing body into a circulation propagation path that can propagate in a state where sound waves circulate;
A prime mover comprising a heater for heating the working medium from the outside, a cooler for cooling the working medium from the outside, and a regenerator for amplifying sound waves between the heater and the cooler in the circulation propagation path. At least one or more power generators that generate power from vibrations of sound waves are provided.

According to the above characteristic configuration, the circulation propagation path through which the sound wave propagates is configured by the housing main body and the partition part that partitions the internal space of the housing main body. That is, unlike the prior art, a sound wave propagation path is not formed by an acoustic cylinder wound a plurality of times in a coil shape, so that no dead space occurs.
For this reason, the thermoacoustic engine which can improve the energy conversion efficiency per unit volume is achieved, aiming at the size reduction.

Further features of the thermoacoustic engine
The partition portion is composed of a thin plate-shaped plate member,
In the acoustic analysis by the boundary element method, the plate-like member is a sound wave formed on the circulation propagation path formed on one side in the plate thickness direction, and the other of the plate-like member in the plate thickness direction. The material and shape are set so that the sound wave formed in the circulation propagation path formed on the side does not change the sound pressure of each other.

In the characteristic configuration, the circulation propagation path through which the sound wave propagates is divided into a circulation propagation path on one side and a circulation propagation path on the other side by a plate-like member as a partition.
In this case, since only the plate member is interposed between the circulation propagation path on one side and the circulation propagation path on the other side, the sound wave propagating through the circulation propagation path on one side is transmitted to the circulation propagation path on the other side. There is a possibility that acoustic waves such as interference may be exerted on the sound wave propagating through the plate-like member.
Therefore, in the above-described characteristic configuration, the sound pressure propagating through the circulation propagation path on one side and the sound wave propagating through the circulation propagation path on the other side of the plate-like member as the partitioning portion fluctuate each other's sound pressure. Since the material and shape are set so as not to interfere with each other (acoustic interference with each other), the sound wave propagating through the circulation propagation path generates a standing wave in the circulation propagation path, Thus, the thermal energy can be converted into the vibration energy of the sound wave in a form in which the vibration energy is amplified.
In addition, in this invention, as shown in the Example mentioned later, as a plate-shaped member as a partition part, stainless steel material (SUS304) is used, a plate surface is made into a rectangular shape, and the edge part along a major axis direction is used. When fixing to the casing body, the width of the plate member in the plate thickness direction is 10 mm or more and 50 mm or less, so that the sound waves partitioned in the plate thickness direction of the plate member cause acoustic interference with each other. It is confirmed by simulation that there is no such thing.

Further features of the thermoacoustic engine
The partition portion is composed of a thin plate-shaped plate member,
The plate-like member is configured such that the material and the shape are set so that the sound wave propagating through the circulation propagation path and the natural vibration of the plate-like member do not resonate with each other in vibration analysis by a finite element method. It is in.

In the characteristic configuration, the circulation propagation path through which the sound wave propagates is divided into a circulation propagation path on one side and a circulation propagation path on the other side by a plate-like member as a partition.
In this case, the plate-like member vibrates at the natural frequency determined by its material, shape, etc., but when the natural frequency and the frequency of the sound wave propagating through the circulation propagation path are close to each other. The natural vibration and sound waves of the plate-like member may resonate, which may reduce the energy conversion efficiency of the thermoacoustic engine, and the plate-like member may be detached from the housing body due to the resonance. There is.
Therefore, in the above-described feature configuration, the partition member is analyzed by vibration analysis using a finite element method so that the natural frequency of the plate member and the frequency of the sound wave propagating through the circulation propagation path do not resonate. Since the material and shape of the plate member are set, it is possible to satisfactorily prevent the natural vibration of the vibration member from resonating with the sound wave propagating through the circulation propagation path. Thereby, thermal energy can be converted into vibration energy of sound waves in a form in which vibration energy is amplified by the regenerator while satisfactorily generating sound waves in the circulation propagation path.
In the present invention, as shown in the examples to be described later, on the premise that the configuration of a general thermoacoustic engine is adopted, as the plate-like member, a plate surface having a rectangular shape is applied, In the case of fixing the end along the long axis direction to the housing body, the width in the plate thickness direction of the plate-like member is made using a stainless steel material (SUS304) or a steel material having a Young's modulus comparable to that of SUS304. In the case of 10 mm, it is found that the resonance between the natural vibration of the plate-like member and the sound wave propagating through the circulation propagation path can be satisfactorily prevented by setting the length of the plate-like member in the minor axis direction to 23 cm or less. Yes.

Further features of the thermoacoustic engine
The partition portion is composed of a thin plate-shaped plate member,
The housing body is composed of a tubular member having a longitudinal direction along the cylinder axis,
The plate-like member divides the internal space of the tubular member into one side space and the other side space along the cylindrical axis direction of the cylindrical member, and both end portions in the cylindrical axis direction of the cylindrical member. In the state where the one side space and the other side space communicate with each other,
The one side space and the other side space form the circulation propagation path.

  According to the above characteristic configuration, a loop-shaped circulation propagation path through which sound waves propagate, one housing body, and one plate-like member that partitions the internal space of the housing body into one space and the other space Therefore, a circulation propagation path without a dead space can be satisfactorily formed by a member having a small number of parts.

Further features of the thermoacoustic engine
The housing body has a shape in which a bottom part and a top part which are end parts in the cylindrical axis direction bulge from the inside to the outside,
The plate-shaped member communicates the one side space and the other side space by a bottom bulge space formed in the bulge portion of the bottom portion and a top bulge space formed in the bulge portion of the top portion. Provided in the form of
The one side space, the other side space, the bottom bulge space, and the top bulge space form the circulation propagation path.

  According to the above characteristic configuration, the casing main body has a shape in which the bottom and the top, which are ends in the axial direction of the cylinder, bulge from the inside to the outside. Therefore, the inner surface forming the inner space has a smooth curved surface. It is possible to achieve a good propagation of sound waves by suppressing reflection of sound waves propagating through the circulation propagation path as the internal space.

Further features of the thermoacoustic engine
The partition is a plurality of plate-like members that partition the internal space of the housing body into the plurality of circulation propagation paths,
Each of the plurality of circulation propagation paths is provided with at least one of the prime mover and the power generator.

  According to the above characteristic configuration, the plurality of circulation propagation paths can be realized by a relatively simple configuration in which the internal space of the housing body is partitioned into the plurality of circulation propagation paths by the plurality of plate-like members.

Schematic configuration diagram of a thermoacoustic engine according to an embodiment The figure which shows the dimensional relationship at the time of performing the acoustic analysis by the boundary element method regarding the thermoacoustic engine which concerns on the said embodiment The figure which shows the dimensional relationship at the time of performing the acoustic analysis by the boundary element method regarding the thermoacoustic engine which concerns on a prior art Diagram showing the path (one-dot chain line) from which the sound pressure is derived in the circulation propagation path and the specific point on the path by acoustic analysis using the boundary element method The graph which shows the sound pressure level in the position (a specific point is included) along the path | route of FIG. Graph showing the natural vibration state of the partition plate and the maximum frequency in each natural vibration state in vibration analysis using finite elements

The thermoacoustic engine 100 according to the embodiment relates to an engine that can be reduced in size and can improve energy conversion efficiency per unit volume.
As shown in FIG. 1, the thermoacoustic engine 100 includes a housing main body C1 filled with a working medium, and a partition C2 that divides the inside of the housing main body C1 into a circulation propagation path that can propagate in a state in which sound waves circulate. It has.
In the thermoacoustic engine 100, in the circulation propagation path formed in this way, the heaters 11a and 11b for heating the working medium from the outside, the coolers 12a and 12b for cooling the working medium from the outside, the heater 11a, 11b and regenerators 13a, 13b that amplify sound waves between the coolers 12a, 12b, and at least one prime mover 10a, 10b (two in this embodiment) and power from vibration of sound waves. A power generator 40 is provided.

When the description is added regarding the casing main body C1 and the partition portion C2 forming the circulation propagation path, as shown in FIGS. 1 and 2, the partition portion C2 is composed of a thin plate-like plate member having a rectangular plate surface. The housing body C1 is formed of a cylindrical member having a longitudinal direction in the direction along the cylinder axis (the direction along the arrow X in FIG. 1). The plate-like member as the partitioning portion C2 divides the internal space of the tubular member into the one side space V1 and the other side space V2 along the axial direction of the cylinder (the direction along the arrow X in FIG. 1). It is provided in a state where the one side space V1 and the other side space V2 communicate with each other at both end portions in the cylindrical axis direction of the member.
More specifically, the casing main body C1 is an elliptical cylindrical member whose cross section in a direction perpendicular to the cylindrical axis direction is substantially elliptical as shown in FIG. Has a bottom bulging space V3 in the shape in which the bottom, which is one end in the cylinder axis direction, bulges from the inside to the outside, and the top, which is the other end in the cylinder axis direction, from the inside to the outside The top bulge space V4 is formed in the inside, and the plate-like member as the partitioning portion C2 is provided avoiding the bottom bulge space V3 and the top bulge space V4.
The circulation propagation path includes a first side space V1, a second side space V2, a bottom bulge space V3, and a top bulge space V4, and is formed so that sound waves circulate and propagate.
That is, in this embodiment, when forming the circulation propagation path, a dead space (a space as indicated by V5 in FIG. 3) is formed like a conventional acoustic cylinder as shown in FIG. 2B. Thus, the configuration is made compact.

[Configuration related to prime mover of thermoacoustic engine]
Although detailed illustration is omitted, the heaters 11a and 11b are jacket portions (not shown) through which the second heat medium HW (for example, engine cooling water) guided by the second heat medium flow passage 70 flows. And fins (not shown) extending from the jacket portion to the inside of the circulation propagation path. The heaters 11a and 11b are heated by the second heat medium HW in which the fins flow through the jacket portion, and heat the working fluid in a form that conducts warm heat from the fins to the working fluid inside the circulation propagation path.

  Similarly, the coolers 12a and 12b include a jacket portion (not shown) through which the first heat medium CW (in the present embodiment, LNG) guided by the first heat medium passage 20 and the jacket. And a fin (not shown) extending from the portion into the circulation propagation path. The coolers 12a and 12b are cooled by the first heat medium CW in which the fins flow through the jacket portion, and the working fluid is cooled in such a manner that cold heat is conducted from the fins to the working fluid inside the circulation propagation path. .

The regenerators 13a and 13b provided between the heaters 11a and 11b and the coolers 12a and 12b are, for example, in a state where the plate surfaces are aligned in a direction orthogonal to the propagation axis direction of the circulation propagation path. A plurality of thin plate-like members (not shown) arranged along the propagation path axial direction.
For example, the thin plate member has a thickness of 50 μm or more and 100 μm or less, and is provided with about 300 to 600 sheets. The thin plate-like member is provided with a large number of through holes (not shown) penetrating in a direction along the axial direction of the propagation path and having a diameter of about 200 μm to 300 μm.

The working fluid exists inside the circulation propagation path in a state in which a minute fluctuation is generated in the axial direction of the propagation path. In other words, the working fluid forms a traveling wave from one side to the other side and a traveling wave from the other side to the one side between the heaters 11a and 11b and the coolers 12a and 12b. Swaying.
When the working fluid forms a traveling wave from the coolers 12a and 12b to the heaters 11a and 11b, the working fluid has a plurality of through holes in the thin plate members as the regenerators 13a and 13b in the vicinity of the heaters 11a and 11b. While passing through, it is heated in contact with the inner wall of the through hole, and is expanded by being directly heated by the fins of the heaters 11a and 11b. On the other hand, when the working fluid forms a traveling wave from the heaters 11a and 11b to the coolers 12a and 12b, a plurality of thin plate members as the regenerators 13a and 13b in the vicinity of the coolers 12a and 12b. When passing through the through-hole, it cools in contact with the inner wall of the through-hole, and shrinks by being directly cooled by the fins of the coolers 12a and 12b.
Thereby, the sound energy as the traveling wave causes self-excited vibration, and the thermal energy is converted into the vibration energy of the sound wave in such a form that the vibration energy is amplified.

  The working medium can be composed of air or the like. Here, since it is desirable that heat exchange in the regenerators 13a and 13b be performed quickly, helium and hydrogen having a high thermal diffusion coefficient are desirable as the working medium. In this embodiment, helium is used as the working medium because it is thermally stable.

As described above, the vibration energy of the sound wave amplified by the prime movers 10a and 10b is converted into electric power by the power generator 40 that is provided in the circulation propagation path and generates electric power from the vibration of the sound wave.
As shown in FIG. 1, the electric power generator 40 includes one rotary blade 40 c and a pair of fixed blades 40 a and 40 b provided with the rotary blade 40 c sandwiched between the rotary propagation paths. In this configuration, the rotary blade 40c generates rotational force by both the sound wave swirled by the one fixed blade 40a and heading toward the rotor blade 40c and the sound wave swirled by the other fixed blade 40b and headed toward the rotary blade 40c. The pair of fixed wings 40a and 40b are provided so that the rotation direction of the rotational force applied to the rotary wing 40c by the sound wave swirled by both is the same direction.
Further, the rotor blade 40c is provided with a rotor (not shown) as an induction generator and the propagation of the circulation propagation path at a portion where the rotor blade 40c is provided in the direction of the propagation path axis of the circulation propagation path. A stator 40d as an induction generator is provided in the road outer diameter portion, and an induced electromotive force E is generated by a coil as the stator 40d when the rotor rotates together with the rotor blade 40c.
By adopting this configuration, vibration energy of sound waves generated inside the circulation propagation path is converted into electrical energy.

In this embodiment, LNG may be formed around the coolers 12a and 12b because LNG is used as the first heat medium CW. Although the said frost is preferable in the meaning which suppresses the spreading | diffusion to the exterior of the cool heat from the coolers 12a and 12b for the part adhering to the circumference | surroundings of the coolers 12a and 12b, There is a risk of taking heat away from the heaters 11a, 11b.
In the circulation propagation path, in the propagation path axial center direction of the circulation propagation path, the heat insulating member 51a having a diameter larger than the outer diameter of the circulation propagation path along the propagation path outer peripheral portion of the portion where the regenerators 13a and 13b are provided. , 51b are provided. Thereby, in each of motor | power_engine 10a, 10b, the frost adhering to the circumference | surroundings of cooler 12a, 12b is prevented spreading to the heater 11a, 11b side.

As described so far, in the thermoacoustic engine 100 according to the embodiment, a compact thermoacoustic engine without a dead space is realized by forming a circulation propagation path with the casing body C1 and the partitioning part C2. Is.
In the thermoacoustic engine 100 according to the embodiment, depending on the shape and material of the plate member as the partitioning portion C2, sound waves formed in the circulation propagation path on one side in the plate thickness direction of the plate member, There is a risk that sound waves formed in the circulation propagation path on the other side in the plate thickness direction of the plate-like member may have an acoustic influence such as interference with each other via the plate-like member.
Therefore, in the thermoacoustic engine 100 according to the embodiment, acoustic analysis by the boundary element method is performed. Hereinafter, the acoustic analysis will be described with reference to FIGS.

In the acoustic analysis, the thermoacoustic engine 100 according to the present invention and the thermoacoustic engine 100 according to the related art were performed in a form in which sound pressures of sound waves in a circulation propagation path through which sound waves propagate were compared.
The thermoacoustic engine 100 according to the present embodiment has a dimensional relationship between the housing body C1 and the partition portion C2 as shown in FIGS. 2A and 2B, and the thin plate member as the partition portion C2 has a plate thickness. Is 10 mm, the length in the minor axis direction is 200 mm, the length in the major axis direction is 3000 mm, and the length of the circulation propagation path is 6500 mm. Further, the material of the thin plate member as the partitioning portion C2 is assumed to be composed of SUS304, and the housing body C1 is a rigid body.
On the other hand, in the thermoacoustic engine 100 according to the prior art, as shown in FIGS. 3 (a) and 3 (b), a loop-shaped acoustic cylinder C having a circular cross section of a radius of 100 mm and a circulation propagation path length of 6500 mm is provided. Provided.
In both the invention according to the embodiment and the prior art, the circulation propagation path is filled with helium as a working medium at a pressure of 1 MPa at 20 ° C.

In the thermoacoustic engine 100 according to this embodiment, when a sound pressure of about 90 dB is generated at the position indicated by A1 in FIG. 4A, the circulation propagation path (specific point) in FIG. The sound pressure generated along the propagation path axis of the propagation paths including A1, A2, A3, and A4 is derived, and is shown by a solid line in FIG.
On the other hand, in the thermoacoustic engine 100 according to the related art, when a sound pressure of about 90 dB is generated at the position indicated by B1 in FIG. The sound pressure generated along the propagation path axis center of propagation paths including A1, B2, B3, and B4 as points is derived and shown by a chain line in FIG.
As can be seen from the results of FIG. 5, the sound pressure of the sound wave propagating through the thermoacoustic engine 100 according to the embodiment and the sound pressure of the sound wave propagating through the thermoacoustic engine 100 according to the related art are as long as the above-described conditions are satisfied. It can be seen that the levels are substantially the same. From this, if it is the conditions mentioned above, the sound wave which propagates the circulation propagation path of the thermoacoustic engine 100 which concerns on the said embodiment will have acoustic influences, such as interference, via the plate-shaped member as the partition part C2. You can see that it has not.
That is, when the above-described conditions are adopted as the thermoacoustic engine 100 according to the embodiment, the plate-like member as the partitioning portion C2 is formed on one side in the plate thickness direction by acoustic analysis by the boundary element method. The sound wave formed in the circulation propagation path and the sound wave formed in the circulation propagation path formed on the other side in the plate thickness direction of the plate-like member have shapes and materials that do not change the sound pressure of each other. It can be said.

In the above test, one of the conditions that most affects the fluctuation of the sound pressure is the plate thickness of the plate-like member as the partitioning portion C2, and the result of performing the acoustic analysis by the boundary element method under different conditions. Under the above-mentioned conditions, when the plate thickness of the plate-like member as the partitioning portion C2 was set to 10 mm or more and 50 mm or less, performance substantially equivalent to the above-described conditions was obtained.
Further, even when a steel material having a Young's modulus comparable to that of SUS304 was adopted as the material of the plate-like member as the partitioning portion C2, performance substantially equivalent to that obtained when SUS304 was adopted was obtained.

Furthermore, in the thermoacoustic engine 100 of the embodiment, depending on the shape and material of the plate member as the partitioning portion C2, the sound wave propagating through the circulation propagation path and the partitioning portion by vibration analysis by the finite element method The natural vibration of the plate-like member as C2 may resonate with each other.
Therefore, in the thermoacoustic engine 100 of the present embodiment, the partition portion is arranged so that the sound wave propagating through the circulation propagation path and the natural vibration of the partition portion C2 do not resonate with each other in the vibration analysis by the finite element method. The material and shape of the plate-like member as C2 are set.

In the general thermoacoustic engine 100, the frequency of the sound wave propagating through the circulation propagation path is often about 100 Hz or less. Therefore, in the vibration analysis by the following finite element method, when SUS304 is used as a plate-like member as the partitioning portion C2, a shape that does not have a natural frequency of 100 Hz or less is specified.
In the general thermoacoustic engine 100, the propagation path length of the circulation propagation path is set to about 6000 to 70000 mm in relation to the amplification factor of the vibration energy of sound waves. Therefore, in the vibration analysis, the length of the long side of the plate member as the partitioning portion C2 is set to 2800 mm. And the length of the short side of the plate member as the partitioning portion C2 is 200 mm, the plate thickness of the plate member is 1 mm, and the 10th order generated in the plate member when the material of the plate member is SUS304. The natural vibration of was derived.
In this case, as shown in FIG. 6B, the plate-like member as the partitioning portion C2 has a mode in which two antinodes are formed at the ends in the major axis direction (maximum frequency: 130.7 Hz), FIG. As shown in (c), a mode that forms three antinodes along the long axis direction (maximum frequency: 131.24 Hz), as shown in FIG. 6 (d), nine antinodes along the long axis direction. Mode (maximum frequency: 140.47 Hz) or the like occurs. Incidentally, in FIGS. 6B, 6C, and 6D, the frequency generated in the plate member as the partitioning portion C2 is three-dimensionally illustrated. The higher or lower part indicates that a higher frequency is generated.
From the result of the vibration analysis, the natural frequency (the above-mentioned maximum frequency) of the plate-like member as the partitioning portion C2 is 130 Hz or more and 140 Hz or less under the above-described conditions. It can be seen that there is no risk of resonance with the generated frequency of 100 Hz.
As a result of intensive studies by the inventors, the natural frequency of the plate-like member gradually decreases when the length of the short side of the plate-like member as the partitioning portion C2 is gradually increased under the above conditions. It was found that the natural frequency of the plate-like member was about 100 Hz when 230 mm was obtained. Therefore, in the above-described conditions, when only the length of the short side of the plate member as the partitioning portion C2 is changed, the length of the short side of the plate member is preferably smaller than 230 mm.

  On the other hand, in the above-mentioned conditions, when the thickness of the plate-like member as the partitioning portion C2 is 2 mm, it has been found that the natural frequency of the plate-like member increases to approximately 270 Hz. That is, when the thickness of the plate-like member as the partitioning portion C2 is changed under the above-described conditions, if the thickness of the plate-like member is 1 mm or more, the natural frequency of the plate-like member is the same as that of the general thermoacoustic engine 100. It can be said that it does not resonate with the frequency of the sound wave.

[Another embodiment]
(1) In the said embodiment, the partition part C2 showed the example which partitions off the inside of the housing body C1 into one circulation propagation path. However, the partition C2 may be configured from a plurality of plate-like members so that the inside of the housing body C1 is partitioned into a plurality of circulation propagation paths. In this case, at least one prime mover 10 and power generator 40 are provided in one circulation propagation path.

(2) In the above embodiment, the case main body C1 has been illustrated as being configured from a cylindrical member. However, for example, the casing main body C1 may have various other shapes such as a rectangular parallelepiped.

(3) In the said embodiment, although the partition part C2 demonstrated as a flat plate-shaped member, the plate surface of the said plate-shaped member does not need to be a plane, A curved surface may be sufficient. Moreover, regarding the one plate-like member, the thickness does not need to be the same, and may have different thicknesses. For example, in the above embodiment, the shape and thickness of the plate-like member as the partitioning portion C2 may be changed so that the cross-sectional shape of the circulation propagation path is circular.

(4) In the above-described embodiment, the number of prime movers provided in one thermoacoustic engine is two, but one may be separately provided, or a configuration in which three or more are provided may be employed.

(5) In the above-described embodiment, an example in which engine cooling water is used as the second heat medium HW has been described. However, other heat medium such as engine exhaust gas can be suitably used.

(6) In the above-described embodiment, an example in which LNG is used as the first heat medium CW has been described, but another heat medium may be used separately.

  The configuration disclosed in the above embodiment (including another embodiment, the same shall apply hereinafter) can be applied in combination with the configuration disclosed in the other embodiment, as long as no contradiction occurs. The embodiment disclosed in this specification is an exemplification, and the embodiment of the present invention is not limited to this. The embodiment can be appropriately modified without departing from the object of the present invention.

  The thermoacoustic engine of the present invention can be reduced in size, and can be effectively used as a thermoacoustic engine capable of improving energy conversion efficiency per unit volume.

10: prime mover 11: heater 12: cooler 13: regenerator 40: power generator 100: thermoacoustic engine C1: casing body C2: partition

Claims (6)

A housing body filled with a working medium;
A partition that partitions the inside of the housing body into a circulation propagation path that can propagate in a state where sound waves circulate;
A prime mover comprising a heater for heating the working medium from the outside, a cooler for cooling the working medium from the outside, and a regenerator for amplifying sound waves between the heater and the cooler in the circulation propagation path. A thermoacoustic engine provided with at least one or more and an electric power generator which generates electric power from vibration of a sound wave. The partition portion is composed of a thin plate-shaped plate member,
In the acoustic analysis by the boundary element method, the plate-like member is a sound wave formed on the circulation propagation path formed on one side in the plate thickness direction, and the other of the plate-like member in the plate thickness direction. 2. The thermoacoustic engine according to claim 1, wherein a material and a shape are set so that a sound wave formed in the circulation propagation path formed on a side does not change a mutual sound pressure. The partition portion is composed of a thin plate-shaped plate member,
The plate-like member is set in material and shape so that the sound wave propagating through the circulation propagation path and the natural vibration of the plate-like member do not resonate with each other in vibration analysis by a finite element method. Item 3. The thermoacoustic engine according to item 1 or 2. The partition portion is composed of a thin plate-shaped plate member,
The housing body is composed of a tubular member having a longitudinal direction along the cylinder axis,
The plate-like member divides the internal space of the tubular member into one side space and the other side space along the cylindrical axis direction of the cylindrical member, and both end portions in the cylindrical axis direction of the cylindrical member. In the state where the one side space and the other side space communicate with each other,
The thermoacoustic engine according to any one of claims 1 to 3, wherein the one side space and the other side space form the circulation propagation path. The housing body has a shape in which a bottom part and a top part which are end parts in the cylindrical axis direction bulge from the inside to the outside,
The plate-shaped member communicates the one side space and the other side space by a bottom bulge space formed in the bulge portion of the bottom portion and a top bulge space formed in the bulge portion of the top portion. Provided in the form of
The thermoacoustic engine according to claim 4, wherein the one side space, the other side space, the bottom bulge space, and the top bulge space form the circulation propagation path. The partition is a plurality of plate-like members that partition the internal space of the housing body into the plurality of circulation propagation paths,
The thermoacoustic engine according to any one of claims 1 to 5, wherein each of the plurality of circulation propagation paths is provided with at least one of the prime mover and the power generator.

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