JP6299186B2 - Heat exchange module for thermoacoustic engine and thermoacoustic engine - Google Patents

Description

  The present invention relates to a heat exchange module for a thermoacoustic engine and a thermoacoustic engine.

  In order to extract energy from waste heat, research and development of Stirling engines are actively conducted. Stirling engine types include α type, β type, γ type, and free piston type. In contrast, recently, research and development of thermoacoustic engines that do not have moving parts such as pistons have been actively conducted.

  The thermoacoustic engine is composed of a tube and a heat source. When the air column in the tube is locally heated or cooled, part of the heat energy is converted into mechanical energy, and the air column causes self-excited vibration. That is, acoustic vibration is generated in the tube. This action can be seen thermodynamically as a prime mover. A thermoacoustic engine uses this action. When a passive machine (refrigerator, cooler) that converts vibration of the air column, that is, acoustic energy into heat energy, is incorporated into the thermoacoustic engine, a refrigeration apparatus (cooling apparatus) is configured.

  As shown in FIGS. 3A and 3B, the conventional heat-acoustic engine heat exchange module 31 used as a prime mover or a passive machine of a thermoacoustic engine has a large number of through holes 33 through which a working fluid passes. A regenerator 32 and two heat exchangers 34 and 35 provided so as to sandwich the regenerator 32 are provided.

  The regenerator 32 has a structure in which a large number of through holes 33 are formed by providing a large number of partition plates vertically and horizontally in a pipe. In the regenerator 32, it is known that the smaller the through-hole 33, the smaller the flow loss and the higher the performance as a prime mover or a passive machine.

  As the heat exchangers 34 and 35, those having fins 36 formed therein are generally used. In the heat exchangers 34 and 35, the fins 36 having a large plate thickness are arranged at a sufficiently wide interval so that heat is easily transmitted and the reciprocating flow of the working fluid in the regenerator 32 is not hindered.

  In addition, there exists patent documents 1-3 as prior art document information relevant to invention of this application.

Japanese Patent Laid-Open No. 05-086978 JP2012-229802A JP 07-293224 A

  However, the above-described conventional heat exchange module 31 for a thermoacoustic engine has a problem that a part of the through-hole 33 of the regenerator 32 is blocked by the thick fin 36. As a result, a region that does not function as the regenerator 32 is generated, and the performance as a prime mover or a passive device is deteriorated.

  As a method for solving this problem, as described in Patent Documents 1 to 3, a method of arranging the regenerator 32 and the heat exchangers 34 and 35 apart from each other can be considered.

  However, the distance for separating the regenerator 32 and the heat exchangers 34 and 35 has not been studied so far. If the distance for separating the regenerator 32 and the heat exchangers 34 and 35 is not appropriate, the desired performance may not be obtained as a prime mover or a passive machine, which is a problem.

  Therefore, an object of the present invention is to provide a heat exchange module for a thermoacoustic engine and a thermoacoustic engine that can solve the above-described problems and can obtain sufficient performance as a prime mover or a passive machine.

The present invention relates to a regenerator in which a large number of through holes for passing a working fluid are formed, and two heat exchanges provided so as to sandwich the regenerator and having fins with a plate thickness larger than the size of the opening of the through hole. A heat exchange module for a thermoacoustic engine, wherein the regenerator and the heat exchanger are spaced apart from each other through a gap, and the length of one side of the square having the same cross-sectional area as the through hole Provided is a heat exchange module for a thermoacoustic engine, wherein the distance between the regenerator and the heat exchanger is d / 3 or more and L / 10 or less, where d is the length and L is the length of the regenerator. .

The present invention also provides a thermoacoustic engine using the heat exchange module for a thermoacoustic engine as a prime mover or a passive machine.

  ADVANTAGE OF THE INVENTION According to this invention, the heat exchange module for thermoacoustic engines which can acquire sufficient performance as a motor | power_engine or a passive machine, and a thermoacoustic engine can be provided.

It is a figure which shows the heat exchange module for thermoacoustic engines which concerns on one Embodiment of this invention, (a) is a disassembled perspective view, (b) is sectional drawing. It is a graph which shows the relationship of the thermoacoustic engine efficiency with respect to the distance Ls between a regenerator and a heat exchanger. It is a figure which shows the conventional heat exchange module for thermoacoustic engines, (a) is a disassembled perspective view, (b) is sectional drawing.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a view showing a heat exchange module for a thermoacoustic engine according to the present embodiment, where (a) is an exploded perspective view and (b) is a cross-sectional view.

  As shown in FIGS. 1A and 1B, a heat exchange module 1 for a thermoacoustic engine is provided so as to sandwich a regenerator 2 in which a large number of through holes 3 through which a working fluid passes are formed. Two heat exchangers 4 and 5 are provided.

  The regenerator 2 has a structure in which a large number of through holes 3 are formed by providing a large number of partition plates vertically and horizontally in the pipe.

  The heat exchangers 4 and 5 are configured by arranging fins 6 having a large thickness at sufficiently wide intervals so that heat can be easily transferred to the working fluid and the reciprocating flow of the working fluid in the regenerator 2 is not hindered. Has been.

  The heat exchange module 1 for a thermoacoustic engine is used as a prime mover or a passive machine in a thermoacoustic engine. By supplying a high-temperature source that is a high-temperature heat medium to one heat exchanger 4 and supplying a low-temperature source that is a low-temperature heat medium to the other heat exchanger 5 to exchange heat with the working fluid, acoustic vibration is generated. It will be a prime mover. Moreover, it arrange | positions so that it may receive the acoustic vibration which the prime mover generate | occur | produced in the flow path of the working fluid which provided the prime mover, for example, introduce | transduces air | atmosphere into one heat exchanger 4 as a high-temperature source, It becomes a passive machine (refrigerator, cooler) that takes out the cold heat output from the atmosphere.

  Now, in the heat exchange module 1 for a thermoacoustic engine according to the present embodiment, the regenerator 2 and the heat exchangers 4 and 5 are arranged apart from each other and have the same cross-sectional area as the through hole 3 of the regenerator 2. When the length of one side of the square is d and the length of the regenerator 2 (the length of the through hole 3) is L, the distance Ls between the regenerator 2 and the heat exchangers 4 and 5 is d / 3. This is L / 10 or less.

  In other words, in the heat exchange module 1 for a thermoacoustic engine, the heat exchangers 4 and 5 are not brought into contact with the regenerator 2 but are arranged through the gap 8, and the gap 8 extends along the tube axis direction. The length Ls is not less than 1/3 times the length d of one side of the square having the same cross-sectional area as the through hole 3 of the regenerator 2 and not more than 1/10 times the length L of the regenerator 2.

  Here, a gap 8 is formed between the regenerator 2 and the heat exchangers 4 and 5 by interposing a spacer (short tube) 7 formed separately from the regenerator 2 and the heat exchangers 4 and 5. However, the spacer 7 may be formed integrally with the regenerator 2 or the heat exchangers 4 and 5.

  The present inventor created a plurality of heat exchange modules for a thermoacoustic engine by changing the distance Ls from 0 to L / 5 in order to find the optimum distance Ls between the regenerator 2 and the heat exchangers 4 and 5. The efficiency of the thermoacoustic engine when the heat exchange module for a thermoacoustic engine was used as a prime mover was obtained. The results are shown in FIG. Thermoacoustic engine efficiency is the ratio of output energy to input energy.

  As shown in FIG. 2, when the distance Ls between the regenerator 2 and the heat exchangers 4 and 5 is less than d / 3, the thermoacoustic engine efficiency is drastically reduced. This is presumably because if the regenerator 2 and the heat exchangers 4 and 5 are too close to each other, the reciprocal flow of the working fluid is blocked by the fins 6 and a region that does not function as the regenerator 2 is generated.

  Further, in the region where the distance Ls between the regenerator 2 and the heat exchangers 4 and 5 is d / 3 or more, the thermoacoustic engine efficiency decreases as the distance Ls increases, and when the distance Ls exceeds L / 10, It can be seen that the rate of decrease in thermoacoustic engine efficiency has also increased. This is because if the regenerator 2 and the heat exchangers 4 and 5 are separated too much, the working fluid reciprocating in the regenerator 2 has a limited distance to move, and therefore the heat exchangers 4 and 5 are included in the regenerator 2. It is considered that the heat from the heat becomes difficult to be transmitted, and the efficiency of converting thermal energy into acoustic energy (or the efficiency of converting thermal energy into acoustic energy) decreases. In order to obtain practical thermoacoustic engine efficiency, the distance Ls between the regenerator 2 and the heat exchangers 4 and 5 needs to be L / 10 or less.

  As described above, in the heat exchange module 1 for a thermoacoustic engine according to the present embodiment, the regenerator 2 and the heat exchangers 4 and 5 are arranged apart from each other, and the regenerator 2 and the heat exchangers 4 and 5 are disposed. The distance Ls is set to d / 3 or more and L / 10 or less.

  With this configuration, it is possible to suppress the generation of a region that does not function as the regenerator 2 due to the influence of the fins 6 and at the same time, it is possible to easily transfer the heat from the heat exchangers 4 and 5 into the regenerator 2. Thus, the output when used as a prime mover or a passive machine can be improved.

  That is, according to this invention, the heat exchange module 1 for thermoacoustic engines which can acquire sufficient performance as a motor | power_engine or a passive machine is realizable.

  The thermoacoustic engine which concerns on this embodiment uses the heat exchange module 1 for thermoacoustic engines which concerns on this embodiment as a motor | power_engine or a passive machine. Since the heat exchange module 1 for a thermoacoustic engine can obtain sufficient performance as a prime mover or a passive machine, a highly efficient thermoacoustic engine can be realized.

  The present invention is not limited to the above-described embodiment, and it is needless to say that various modifications can be made without departing from the spirit of the present invention.

  For example, in the above embodiment, the case where the heat exchangers 4 and 5 using the fins 6 are used has been described. However, the present invention is not limited to this. The present invention can also be applied to heat exchangers 4 and 5 of a type in which a flow path is formed in a pipe.

1 Heat exchange module for thermoacoustic engine 2 Regenerator 3 Through holes 4, 5 Heat exchanger 6 Fin

Claims (2)

A regenerator in which a number of through-holes for passing a working fluid are formed;
Two heat exchangers provided so as to sandwich the regenerator and having fins with a plate thickness larger than the size of the opening of the through hole ;
A heat exchange module for a thermoacoustic engine comprising:
The regenerator and the heat exchanger are spaced apart via a gap ,
When the length of one side of the square having the same cross-sectional area as the through hole is d and the length of the regenerator is L, the distance between the regenerator and the heat exchanger is d / 3 or more L / 10 A heat exchange module for a thermoacoustic engine, characterized by: A thermoacoustic engine using the heat exchange module for a thermoacoustic engine according to claim 1 as a prime mover or a passive machine.