JP6760026B2 - Thermoacoustic engine - Google Patents

Description

The techniques disclosed herein relate to thermoacoustic engines that use a mixture of a non-condensable fluid and a condensable fluid as the working fluid.

As a prior art, for example, there is a phase change type thermoacoustic engine disclosed in Patent Document 1 below. This thermoacoustic engine uses a mixture of a non-condensable fluid and a condensable fluid as a working fluid, and the phase change of the condensable fluid makes it possible to utilize low-temperature heat source energy.

JP-A-2009-74722

However, in the thermoacoustic engine of the prior art, a state may occur in which the amount of condensable fluid existing in the vicinity of the stack that causes the thermoacoustic phenomenon is not appropriate. For example, if a large amount of condensable fluid is condensed in a place other than the stack due to the influence of the environmental temperature of the engine or the like, the amount of the condensable fluid existing in the vicinity of the stack is reduced. In such a case, there is a problem that the effect of the phase change of the condensing fluid cannot be sufficiently exerted and the energy exchange performance is deteriorated.

The technique disclosed herein has been made in view of the above points, and an object of the present invention is to provide a phase-changing thermoacoustic engine capable of stably exhibiting energy exchange performance.

In order to achieve the above objectives, the disclosed thermoacoustic heat engines
A pipe member (20) in which a working fluid (10), which is a mixture of a non-condensable fluid (11) and a condensable fluid (12), is filled therein to form a sound wave transmission path for the working fluid in the gas phase.
A heat absorber (32) provided on the pipe member to absorb heat from the outside to the working fluid, and
A radiator (33) provided on the pipe member to dissipate heat from the working fluid to the outside,
A stack (31) provided on a tube member, sandwiched between a heat absorber and a radiator, and performing energy conversion between thermal energy and acoustic energy of sound waves by a thermoacoustic effect.
A liquid storage unit (25) provided on the pipe member for storing the condensable fluid of the liquid phase, and
A liquid guide section (24) provided on the pipe member and guiding the condensable fluid that has become a liquid phase in the transmission path to the liquid storage section,
A supply unit (50, 250, 350) for supplying the condensable fluid of the liquid phase stored in the liquid storage unit to the stack is provided .
Supply unit, that have a temperature controller for temperature control by heating the condensable fluid reservoir liquid phase in the liquid storage portion (250, 350).

According to this, the condensable fluid that has become a liquid phase in the transmission path can be guided to the liquid storage part by the liquid conducting part. Then, the condensable fluid of the liquid phase stored in the liquid storage unit can be supplied to the stack. Therefore, even if a large amount of condensable fluid is condensed outside the stack, the condensable fluid that has become a liquid phase can be collected in the liquid storage section and supplied to the stack, and the condensable fluid can be supplied to the stack. The effect of latent heat accompanying the gas-liquid phase change can be surely exhibited. In this way, the energy exchange performance can be stably exhibited.

In order to achieve the above objectives, the disclosed thermoacoustic heat engines
A pipe member (20) in which a working fluid (10), which is a mixture of a non-condensable fluid (11) and a condensable fluid (12), is filled therein to form a sound wave transmission path for the working fluid in the gas phase. ,
A heat absorber (32) provided on the pipe member to absorb heat from the outside to the working fluid, and
A radiator (33) provided on the pipe member to dissipate heat from the working fluid to the outside,
A stack (31) provided on a tube member, sandwiched between a heat absorber and a radiator, and performing energy conversion between thermal energy and acoustic energy of sound waves by a thermoacoustic effect.
A liquid storage unit (25) provided on the pipe member for storing the condensable fluid in the liquid phase, and
A liquid guide section (24) provided on the pipe member and guiding the condensable fluid that has become a liquid phase in the transmission path to the liquid storage section,
A supply unit (50, 250, 350) for supplying the condensable fluid of the liquid phase stored in the liquid storage unit to the stack is provided.
The liquid-conducting portion has an inclined surface (24) that is formed so as to face the transmission path on the lower side of the transmission path and is gradually positioned downward as it approaches the liquid storage section .
The scope of claims and the reference numerals in parentheses described in this section indicate the correspondence with the specific means described in the embodiments described later as one embodiment, and limit the scope of the disclosed technology. It's not a thing.

It is a schematic block diagram of the thermoacoustic engine which concerns on 1st Embodiment. FIG. 1 is an enlarged cross-sectional view of part II of FIG. It is an enlarged cross-sectional view of the modification, and shows the part corresponding to FIG. It is a schematic block diagram of the thermoacoustic engine which concerns on 2nd Embodiment. It is a schematic block diagram of the thermoacoustic engine which concerns on 3rd Embodiment. It is a schematic block diagram of the thermoacoustic engine which concerns on 4th Embodiment. FIG. 6 is a sectional view taken along line VII-VII of FIG.

Hereinafter, a plurality of modes for carrying out the disclosure technique will be described with reference to the drawings. In each form, the same reference numerals may be attached to the parts corresponding to the matters described in the preceding forms, and duplicate explanations may be omitted. When only a part of the configuration is described in each form, the other parts of the configuration are the same as those described above. Not only the combinations of the parts specifically described in each embodiment, but also the combinations of the embodiments can be partially combined as long as the combination does not cause any trouble.

(First Embodiment)
The first embodiment to which the disclosed technique is applied will be described with reference to FIGS. 1 to 3.

The thermoacoustic engine 1 shown in FIG. 1 is used, for example, mounted on a vehicle. The thermoacoustic engine 1 is mounted on the vehicle with the direction indicated by the arrow in the figure as the vertical direction. The thermoacoustic engine 1 includes a pipe member 20, a sound wave generating unit 30, a cooler 40, and a supply unit 50. The tube member 20 is connected as a resonance tube that communicates the first loop tube 21 formed in a loop shape, the second loop tube 22 formed in a loop shape, and the first loop tube 21 and the second loop tube 22. It has a tube 23.

The pipe member 20 is, for example, a stainless steel pipe having a circular cross section. The working fluid 10 is sealed inside the pipe member 20. Inside the pipe member 20, a mixture of the non-condensable fluid 11 and the condensable fluid 12 is sealed as the working fluid 10. The non-condensable fluid 11 is always in a vapor phase state inside the pipe member 20. The non-condensable fluid 11 is, for example, helium. The non-condensable fluid 11 is not limited to helium. As the non-condensable fluid 11, for example, an inert gas such as nitrogen or argon or air can be used. As the non-condensable fluid 11, the above-mentioned gas can be used alone or in combination.

The condensable fluid 12 undergoes a phase change between the gas phase state and the liquid phase state inside the pipe member 20 according to the temperature and the saturated vapor pressure. The condensable fluid 12 is, for example, water. The condensable fluid 12 is not limited to water. As the condensable fluid 12, for example, carbonic acid or chlorofluorocarbon can be used. As the condensing fluid 12, the above-mentioned fluid can be used alone or in combination.

The pipe member 20 is filled with the working fluid 10 at a pressure of, for example, about 0.1 to 3.0 MPa. The pipe member 20 forms a sound wave transmission path of the gas phase working fluid 10 inside the pipe member 20. The thermoacoustic engine 1 is a so-called double loop type thermoacoustic engine.

The first loop tube 21 is provided with a sound wave generating unit 30. The sound wave generation unit 30 is a prime mover in the thermoacoustic engine 1 and has a sound wave generation function of converting thermal energy into acoustic energy. The first loop pipe 21 has upper and lower horizontal pipes 211 and 212 and left and right vertical pipes 213 and 214, and is piped in a rectangular shape. In this example, the sound wave generating unit 30 is arranged in a vertical pipe 214 extending in the vertical direction.

The sound generation unit 30 includes a stack 31 as a heat storage device housed inside the first loop tube 21, a high temperature side heat exchanger 32 provided at one end of the stack 31 which is a high temperature end, and a low temperature of the stack 31. It has a low temperature side heat exchanger 33 provided at the other end, which is the end. The high temperature side heat exchanger 32 is, for example, a heat absorber that heats the working fluid 10 by absorbing waste heat from an internal combustion engine or a heat generating device mounted on a vehicle. In the high temperature side heat exchanger 32, for example, the working fluid 10 can absorb heat by heat exchange between the cooling medium for cooling the internal combustion engine and the heat generating device and the working fluid 10. Further, the high temperature side heat exchanger 32 may be one that causes the working fluid 10 to absorb heat by, for example, heat exchange between the exhaust gas of the internal combustion engine and the working fluid 10.

On the other hand, the low temperature side heat exchanger 33 is a radiator that radiates heat from the working fluid 10 to the heat transport medium by heat exchange with the heat transport medium to cool the working fluid 10. The stack 31 sandwiched between the high temperature side heat exchanger 32 and the low temperature side heat exchanger 33 is composed of a structure in which a plurality of stainless steel metal meshes are laminated, as illustrated in FIG. As a result, fine passages of the working fluid 10 are formed in the stack 31 at minute intervals. As illustrated in FIG. 3, the stack 31 may be a honeycomb structure made of ceramics.

On the passage wall in the stack 31, a temperature gradient is generated in the extending direction of the first loop pipe 21 due to the functions of the heat absorbers and radiators arranged at both ends. When the working fluid 10 moves along this temperature gradient in the fine passage in the stack 31 where the temperature gradient is generated, a self-excited pressure fluctuation is generated in the working fluid 10 of the gas phase due to the thermoacoustic effect. That is, the stack 31 generates a sound wave due to thermoacoustic self-excited vibration in the working fluid 10. In the stack 31, heat energy is converted into acoustic energy, and sound waves are applied to the working fluid 10 of the gas phase, that is, the mixed gas of the non-condensable fluid 11 and the gas phase condensing fluid 12A which is the gas phase condensing fluid 12. generate. In the sound wave transmission path in the first loop tube 21, traveling wave and standing wave sound waves traveling in the direction indicated by the arrow in FIG. 1 are generated from the high temperature end side of the sound wave generating unit 30.

In the sound wave generating unit 30, the condensable fluid 12 of the working fluid 10 evaporates in the high temperature side heat exchanger 32 and condenses in the low temperature side heat exchanger 33. The condensable fluid 12 that has become a liquid phase in the low temperature side heat exchanger 33 passes through the stack 31 and moves to the high temperature side heat exchanger 32 side. With such a phase change of the condensing fluid 12, heat transfer in the stack 31 is promoted. Therefore, even when the temperature of the transport medium for transporting waste heat to the high temperature side heat exchanger 32 is relatively low and the temperature difference between the high and low temperature ends of the stack 31 is small, it is relatively due to the phase change of the condensing fluid 12. A large heat flow can be formed. As a result, a relatively large work flow can be formed by energy conversion in the stack 31, and a relatively large acoustic energy can be generated as a sound wave.

A part of the sound wave in the first loop pipe 21 is propagated into the second loop pipe 22 through the connecting pipe 23. The upstream end of the connecting pipe 23 in the sound wave traveling direction is connected to the first loop pipe 21, and the downstream end in the sound wave traveling direction is connected to the second loop pipe 22. In the vertical pipe 214 of the first loop pipe 21, the sound wave generating portion 30 is arranged relatively close to the connecting portion of the connecting pipe 23.

The second loop pipe 22 is provided with a cooler 40. The cooler 40 is a passive machine in the thermoacoustic engine 1 and has a heat storage function of converting acoustic energy into thermal energy. The cooler 40 is an output unit that converts the acoustic energy of the sound wave from the sound wave generating unit 30 into thermal energy and outputs the thermal energy. The second loop pipe 22 has upper and lower horizontal pipes 221 and 222 and left and right vertical pipes 223 and 224, and is piped in a rectangular shape. In this example, the cooler 40 is arranged in a vertical pipe 224 extending in the vertical direction.

The cooler 40 includes a stack 41 as a regenerator housed inside the second loop pipe 22, a high temperature side heat exchanger 42 provided at one end of the stack 41 which is a high temperature end, and a low temperature end of the stack 41. It has a low temperature side heat exchanger 43 provided at the other end. The high temperature side heat exchanger 42 is a heat exchanger that dissipates the heat of the working fluid 10 to the heat transport medium by heat exchange. The low temperature side heat exchanger 43 is an endothermic device that absorbs the heat of the heat transport medium into the working fluid 10 by heat exchange.

Like the stack 31, the stack 41 sandwiched between the high-temperature side heat exchanger 42 and the low-temperature side heat exchanger 43 is composed of, for example, a structure in which a plurality of stainless steel metal meshes are laminated. As a result, fine work gas passages are formed in the stack 41 at minute intervals. The stack 41 may be, for example, a honeycomb structure made of ceramics.

Sound waves are propagated into the second loop pipe 22 through the connecting pipe 23, and when they enter the fine passage in the stack 41 from the high temperature end side, the acoustic energy is changed to the thermal energy between the working fluid 10 and the passage wall. The conversion and the conversion from thermal energy to acoustic energy are repeated. In the process, heat is transferred from the low temperature end to the high temperature end of the stack 41. The cooler 40 is a heat pump that uses acoustic energy to transfer heat from the low temperature end to the high temperature end of the stack 41.

In the vertical pipe 224 of the second loop pipe 22, the cooler 40 is arranged relatively close to the connection portion of the connecting pipe 23. The cooler 40 is arranged at a portion upstream of the connecting pipe 23 connection portion in the sound wave traveling direction in the second loop pipe 22, and the high temperature side heat exchanger 42, the stack 41, and the low temperature side heat exchanger 43 are arranged in this order. Have been placed.

The cooler 40 converts acoustic energy into thermal energy, which is energy other than acoustic energy, and outputs the energy. The cooler 40 outputs heat energy as cold heat from the low temperature side heat exchanger 43 provided at the low temperature end of the stack 41.

The thermoacoustic engine 1 of the present embodiment is, for example, a device suitable for application to an air conditioner for a vehicle. For example, in the low temperature side heat exchanger 43 of the cooler 40, the heat transport medium cooled by heat exchange with the working fluid 10 can be circulated to the cooler core to cool the vehicle interior. The cold heat output from the low temperature side heat exchanger 43 is transported to the cooler core by the heat transport medium, and the air blown into the vehicle interior in the cooler core is cooled.

The pipe member 20 of the present embodiment is provided with a liquid storage unit 25. In this example, the liquid storage unit 25 is provided below the connection portion between the horizontal pipe 212 and the vertical pipe 213 of the first loop pipe 21. The liquid storage unit 25 has a cup-like shape in which the pipe member 20 is bulged downward, and can store the liquid phase condensing fluid 12B, which is the liquid phase condensing fluid 12, inside. The liquid storage portion 25 is not limited to the one formed by bulging the pipe member 20. The liquid storage unit 25 may have a recessed portion that is recessed downward and may be capable of storing liquid in the recess. For example, the container body may be attached to the pipe member 20.

In the pipe member 20, the lateral pipe 212 of the first loop pipe 21 extends from one end in the extending direction of the connecting pipe 23, and the lateral pipe 212 of the second loop pipe 22 extends from the other end in the extending direction of the connecting pipe 23. The pipe 222 extends. In this example, the horizontal pipe 212, the connecting pipe 23, and the horizontal pipe 222 are formed as continuous pipes having the same diameter arranged coaxially. The continuous pipe composed of the horizontal pipe 212, the connecting pipe 23, and the horizontal pipe 222 is an inclined pipe slightly inclined with respect to the horizontal direction. The continuous pipe including the horizontal pipe 212, the connecting pipe 23, and the horizontal pipe 222 is lower at the end on the liquid storage portion 25 formation side on the right side of the drawing than at the left end shown. That is, the horizontal pipe 212, the connecting pipe 23, and the horizontal pipe 222 form an inclined pipe that is gradually positioned downward as it approaches the liquid storage portion. Therefore, the lower surface portions of the horizontal pipe 212, the connecting pipe 23, and the horizontal pipe 222 facing the sound wave transmission passage form an inclined surface 24 that is gradually positioned downward as it approaches the liquid storage portion 25.

In the thermoacoustic engine 1, when the condensing fluid 12 is condensed in a place other than the stack 31 of the sound wave generating unit 30 and the low temperature side heat exchanger 33 due to the influence of the environmental temperature or the like to generate the liquid phase condensing fluid 12B. There is. The liquid-phase condensing fluid 12B generated at a location other than the sound wave generating portion 30 in the pipe member 20 flows downward along the inclined surface 24 and is collected in the liquid storage portion 25. The inclined surface 24 formed on the pipe member 20 corresponds to a liquid guide portion that guides the liquid phase condensing fluid 12B that has become a liquid phase in the sound wave transmission path to the liquid storage portion 25. The inclined surface 24 that functions as a liquid guide is provided by an inclined pipe including a horizontal pipe 212, a connecting pipe 23, and a horizontal pipe 222.

As shown in FIG. 1, the thermoacoustic engine 1 includes a supply unit 50 for supplying the liquid phase condensing fluid 12B stored in the liquid storage unit 25 to the stack 31 of the sound wave generation unit 30. The supply unit 50 has a supply pipe 51 and a pump device 52 provided in the supply pipe 51. The supply pipe 51 connects the liquid storage unit 25 and the stack 31. The upstream end of the supply pipe 51 is open to the bottom of the liquid storage portion 25 in this example. On the other hand, the downstream end of the supply pipe 51 opens at the height of the upper end of the stack 31 in this example, as shown in FIGS. 2 and 3. Specifically, the downstream end of the supply pipe 51 opens to the side of the connection portion between the stack 31 and the low temperature side heat exchanger 33.

The pump device 52 pumps the liquid-phase condensing fluid 12B stored in the liquid storage unit 25 toward the stack 31 via the supply pipe 51. As a result, the liquid phase condensable fluid 12B collected in the liquid storage unit 25 is supplied to the stack 31. The pumping device 52 is turned on when the amount of condensable fluid 12 in the stack 31 is insufficient for a suitable amount based on energy conversion efficiency. When the pump device 52 is turned on and put into an operating state, the liquid phase condensing fluid 12B stored in the liquid storage unit 25 is sent to the predetermined amount stack 31. The liquid-phase condensable fluid 12B supplied to the stack 31 enters the stack 31 due to the capillary phenomenon, and spreads over the entire area in the stack 31 due to the capillary phenomenon and gravity.

According to the thermoacoustic engine 1 of the present embodiment, the following effects can be obtained.

The thermoacoustic engine 1 includes a tube member 20, a high temperature side heat exchanger 32 as a heat absorber, a low temperature side heat exchanger 33 as a radiator, a stack 31, a liquid storage unit 25, an inclined surface 24 as a liquid guide unit, and A supply unit 50 is provided. The tube member 20 is filled with the working fluid 10 which is a mixture of the non-condensable fluid 11 and the condensing fluid 12 to form a sound wave transmission path of the working fluid in the gas phase. The high temperature side heat exchanger 32 is provided on the pipe member 20 and absorbs heat from the outside to the working fluid 10. The low temperature side heat exchanger 33 is provided on the pipe member 20 and dissipates heat from the working fluid 10 to the outside. The stack 31 is provided on the tube member 20, is sandwiched between a heat absorber and a radiator, and performs energy conversion between thermal energy and acoustic energy of sound waves by a thermoacoustic effect. The liquid storage unit 25 is provided in the pipe member 20 and stores the liquid phase condensing fluid 12B. The inclined surface 24 is provided on the pipe member 20 and guides the liquid phase condensing fluid 12B, which has become a liquid phase in the sound wave transmission path, to the liquid storage unit 25. The supply unit 50 supplies the liquid phase condensing fluid 12B stored in the liquid storage unit 25 to the stack 31.

According to this, the liquid phase condensing fluid 12B which became the liquid phase in the sound wave transmission path can be guided to the liquid storage part 25 by the inclined surface 24 which is the liquid conducting part. Then, the liquid phase condensable fluid 12B stored in the liquid storage unit 25 can be supplied to the stack 31. Therefore, even if a large amount of condensable fluid is condensed other than the stack 31, the liquid phase condensable fluid 12B that has become a liquid phase is collected in the liquid storage unit 25, and the liquid phase condensable fluid 12B is supplied to the stack 31. be able to. As a result, the effect of latent heat accompanying the gas-liquid phase change of the condensing fluid 12 can be surely exhibited in the stack 31. In this way, the energy exchange performance can be stably exhibited.

Further, the supply unit 50 has a pump device 52 that pumps the liquid phase condensing fluid 12B stored in the liquid storage unit 25 to the stack 31. According to this, the liquid phase condensing fluid 12B stored in the liquid storage unit 25 can be reliably supplied to the stack 31 by pumping with the pump device 52.

Further, the liquid guide portion of the present embodiment has an inclined surface 24 which is formed so as to face the sound wave transmission path on the lower side of the sound wave transmission path and is gradually positioned downward as it approaches the liquid storage section 25. According to this, the liquid phase condensing fluid 12B which has become a liquid phase in the sound wave transmission path can be easily guided to the liquid storage unit 25 by using the inclined surface 24.

Further, the inclined surface 24 is formed in a part of the pipe member 20, and is provided by a horizontal pipe 212, a connecting pipe 23, and a horizontal pipe 222 that form an inclined pipe that is gradually positioned downward as it approaches the liquid storage portion 25. To. According to this, the inclined surface 24 for flowing the liquid phase condensing fluid 12B which became the liquid phase in the sound wave transmission path toward the liquid storage unit 25 can be easily provided by the inclined pipe.

(Second Embodiment)
Next, the second embodiment will be described with reference to FIG.

The second embodiment has a different configuration of the supply unit as compared with the first embodiment described above. The same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. The components having the same reference numerals as those in the drawings according to the first embodiment and the other configurations not described in the second embodiment are the same as those in the first embodiment and have the same effects.

As shown in FIG. 4, in the present embodiment, the liquid storage unit 25 is provided below the connection portion between the horizontal pipe 212 and the vertical pipe 214 of the first loop pipe 21. In the pipe member 20 of the present embodiment, the connecting pipe 23 and the horizontal pipe 222 are formed as continuous pipes having the same diameter arranged coaxially. As is clear from FIG. 4, the continuous pipe composed of the connecting pipe 23 and the horizontal pipe 222 is an inclined pipe slightly inclined with respect to the horizontal direction. On the other hand, the horizontal pipe 212 connected to the connecting pipe 23 on the anti-horizontal pipe 222 side is an inclined pipe slightly inclined to the side opposite to the continuous pipe composed of the connecting pipe 23 and the horizontal pipe 222 in the horizontal direction. There is.

In the continuous pipe composed of the connecting pipe 23 and the horizontal pipe 222, the end portion on the liquid storage portion 25 forming side on the right side in the drawing is lower than the left end portion in the drawing. On the other hand, the horizontal pipe 212 is lower at the end on the left side of the drawing on the liquid storage portion 25 formation side than at the right end in the drawing. That is, the horizontal pipe 212, the connecting pipe 23, and the horizontal pipe 222 form an inclined pipe that is gradually positioned downward as it approaches the liquid storage unit 25. Therefore, the lower surface portion of the horizontal pipe 212 facing the sound wave transmission passage and the lower surface portion of the connecting pipe 23 and the horizontal pipe 222 facing the sound wave transmission passage are both inclined surfaces 24 that are gradually positioned downward as they approach the liquid storage portion 25. To form. Also in the present embodiment, the inclined surface 24 that functions as a liquid guide portion is provided by an inclined pipe made of a horizontal pipe 212 and an inclined pipe made of a connecting pipe 23 and a horizontal pipe 222.

The thermoacoustic engine of the present embodiment uses an electric heater 250, which is an example of a heating device, as a supply unit for supplying the liquid phase condensing fluid 12B stored in the liquid storage unit 25 to the stack 31 of the sound wave generation unit 30. I have. The electric heater 250 is provided in the liquid storage unit 25 and is provided so as to be able to heat the liquid phase condensing fluid 12B stored in the liquid storage unit 25. When the electric heater 250 is energized and the liquid phase condensing fluid 12B of the liquid storage unit 25 is heated, the liquid phase condensing fluid 12B is vaporized to become a gas phase condensing fluid 12A, and the generated gas phase condensing fluid 12A is generated. 12A diffuses into the sound transmission path.

When the amount of the condensable fluid 12 in the stack 31 is insufficient for a suitable amount based on the energy conversion efficiency, the electric heater 250 is turned on and the liquid phase condensable fluid 12B stored in the liquid storage unit 25 is turned on. Becomes a vapor-phase condensing fluid 12A and is supplied to the stack 31. The electric heater 250 is a temperature control device that heats and adjusts the temperature of the liquid phase condensing fluid 12B stored in the liquid storage unit 25, and corresponds to the supply unit in the present embodiment.

In the thermoacoustic engine of the present embodiment, the supply unit has a temperature control device that heats the liquid phase condensing fluid 12B stored in the liquid storage unit 25 to control the temperature. According to this, the liquid phase condensing fluid 12B is vaporized by heating the liquid phase condensing fluid 12B stored in the liquid storage unit 25 by the temperature control device, and the gas phase condensing fluid 12A is supplied to the stack 31. be able to. Further, the supply unit of the present embodiment can have a relatively simple configuration having no movable unit. The temperature control device is not limited to the electric heater 250, and may be any device that can heat the liquid phase condensing fluid 12B stored in the liquid storage unit 25.

(Third Embodiment)
Next, the third embodiment will be described with reference to FIG.

The third embodiment has a different configuration of the temperature control device used as the supply unit as compared with the second embodiment described above. The same parts as those in the first and second embodiments are designated by the same reference numerals, and the description thereof will be omitted. The components having the same reference numerals as the drawings according to the first and second embodiments, and the other configurations not described in the third embodiment are the same as those in the first and second embodiments, and have the same effects. It is a thing.

As shown in FIG. 5, the thermoacoustic engine of the present embodiment uses the Peltier element 350 as a supply unit for supplying the liquid phase condensing fluid 12B stored in the liquid storage unit 25 to the stack 31 of the sound wave generation unit 30. I have. The Peltier element 350 is provided on the lower surface of the bottom portion of the liquid storage unit 25, and is provided so that the liquid phase condensing fluid 12B stored in the liquid storage unit 25 can be heated and cooled. When the Peltier element 350 is energized and the surface on the liquid storage unit side becomes a heat generating surface, the liquid phase condensing fluid 12B of the liquid storage unit 25 is heated, and the liquid phase condensing fluid 12B is vaporized to become the gas phase condensing fluid 12A. Become. Then, the generated vapor-phase condensing fluid 12A diffuses into the sound wave transmission passage. When the polarity of the current of the Peltier element 350 is reversed and the surface on the liquid storage unit side becomes an endothermic surface, the liquid phase condensing fluid 12B of the liquid storage unit 25 is cooled, and the liquid phase condensing fluid stored in the liquid storage unit 25 is cooled. The vapor phase condensing fluid 12A condenses on the surface of 12B.

When the amount of the condensable fluid 12 in the stack 31 is insufficient for a suitable amount based on the energy conversion efficiency, the Peltier element 350 is energized to generate heat, and the stored liquid-phase condensing fluid 12B is heated. The mode is set. When the heating mode is set, the liquid phase condensing fluid 12B stored in the liquid storage unit 25 becomes the gas phase condensing fluid 12A and is supplied to the stack 31.

When the amount of the condensing fluid 12 in the stack 31 is excessive with respect to a suitable amount based on the energy conversion efficiency, the Peltier element 350 is back-energized to absorb heat and cool the stored liquid-phase condensing fluid 12B. Cooling mode is set. When the cooling mode is set, as the temperature of the liquid phase condensing fluid 12B stored in the liquid storage unit 25 drops, the gas phase condensing fluid 12A in the pipe member 20 condenses and enters the liquid storage unit 25. Will be collected in. In this way, the Peltier element 350 can switch between a heating mode in which the liquid phase condensing fluid 12B stored in the liquid storage unit 25 is heated to control the temperature and a cooling mode in which the liquid phase condensing fluid 12B is cooled to control the temperature. The Peltier element 350 is a temperature control device configured to be able to switch between a heating mode and a cooling mode, and corresponds to a supply unit in the present embodiment.

In the thermoacoustic engine of the present embodiment, as in the second embodiment, the supply unit has a temperature control device that heats the liquid phase condensing fluid 12B stored in the liquid storage unit 25 to control the temperature. .. According to this, the liquid phase condensing fluid 12B is vaporized by heating the liquid phase condensing fluid 12B stored in the liquid storage unit 25 by the temperature control device, and the gas phase condensing fluid 12A is supplied to the stack 31. be able to. Further, the supply unit of the present embodiment can have a relatively simple configuration having no movable unit.

Further, the Peltier element 350, which is a temperature control device, has a heating mode for heating the liquid phase condensing fluid 12B stored in the liquid storage unit 25 and cooling the liquid phase condensing fluid 12B stored in the liquid storage unit 25. It is configured to be able to switch between the cooling mode that adjusts the temperature. According to this, the temperature controller can easily switch between the heating mode and the cooling mode to adjust the amount of condensable fluid present in the stack 31.

By making it possible to set the cooling mode by the temperature control device, when the amount of the condensable fluid 12 in the stack 31 is excessive with respect to a suitable amount, a part of the condensable fluid 12 can be recovered. Therefore, it is possible to prevent the excess condensable fluid 12 from hindering heat exchange and the excess condensable fluid 12 from blocking the fine passages in the stack. Further, it is possible to prevent the gas-phase condensing fluid 12A from becoming excessive inside the pipe member 20 and causing thermal energy loss due to the heat pipe effect.

(Fourth Embodiment)
Next, the fourth embodiment will be described with reference to FIGS. 6 and 7.

In the fourth embodiment, the posture of the pipe member is different from that in the first embodiment described above. The same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. The components having the same reference numerals as those in the drawings according to the first embodiment and the other configurations not described in the fourth embodiment are the same as those in the first embodiment and have the same effects.

The thermoacoustic engine of the present embodiment is mounted on the vehicle with the front and back directions of the illustrated paper facing up and down. The front side of the paper corresponds to the upper side of the thermoacoustic engine, and the back side of the paper corresponds to the lower side of the thermoacoustic engine. As shown in FIG. 6, the liquid storage unit 25 of the present embodiment is provided in the second loop pipe 22 in the vicinity of the low temperature side heat exchanger 43 of the cooler 40.

As shown in FIG. 7, the second loop pipe 22 is composed of at least a part of the inclined pipe slightly inclined with respect to the horizontal plane. The second loop pipe 22 is inclined so that the position of the low temperature side heat exchanger 43 is slightly lower than the position of the high temperature side heat exchanger 42 at the cooler 40 arrangement portion. The second loop pipe 22 is provided with a liquid storage unit 25 at a portion close to the low temperature side heat exchanger 43.

The second loop pipe 22 is lower at the cooler 40 arrangement portion at the end on the left side of the drawing on the liquid storage portion 25 formation side than at the right end in the drawing. That is, the cooler 40 arrangement portion of the second loop pipe 22 constitutes an inclined pipe that is gradually positioned downward as it approaches the liquid storage portion 25. Therefore, the lower surface portion of this portion facing the sound wave transmission passage forms an inclined surface 24 that is gradually positioned downward as it approaches the liquid storage portion 25.

The second loop pipe 22 also constitutes an inclined pipe that is gradually positioned downward as it approaches the liquid storage unit 25 at a portion on the left side of FIG. 7 in the figure. Therefore, the lower surface portion of this portion facing the sound wave transmission passage also forms an inclined surface 24 that is gradually positioned downward as it approaches the liquid storage portion 25. Also in this embodiment, the inclined surface 24 that functions as the liquid guide portion is provided by the inclined pipe portion of the second loop pipe 22.

As shown in FIG. 6, the downstream end of the supply pipe 51 of the present embodiment is open to the high temperature end of the stack 31. Specifically, the downstream end of the supply pipe 51 opens at the connection portion between the stack 31 and the high temperature side heat exchanger 32. The pump device 52 pumps the liquid-phase condensing fluid 12B stored in the liquid storage unit 25 toward the stack 31 via the supply pipe 51. As a result, the liquid phase condensable fluid 12B collected in the liquid storage unit 25 is supplied to the stack 31.

In the thermoacoustic apparatus of the present embodiment, the temperature of the low temperature side heat exchanger 43 arrangement portion is most likely to be low. Therefore, the gas phase condensing fluid 12A tends to condense in the vicinity of the low temperature side heat exchanger 43 to become the liquid phase condensing fluid 12B. A part of the liquid phase condensing fluid 12B generated by the low temperature side heat exchanger 43 enters the stack 41, and the remaining part is guided to the inclined surface 24 and is reliably stored in the liquid storage unit 25. .. Then, the liquid phase condensable fluid 12B stored in the liquid storage unit 25 is supplied to the stack 31 as needed.

In the thermoacoustic device of the present embodiment, the second loop pipe 22 has a slightly inclined inclined pipe portion, and a cooler 40 is arranged in this inclined pipe portion. Therefore, it is easier to suppress performance deterioration due to natural convection of the gas phase working fluid than when the cooler 40 is provided in the upright pipe portion extending in the vertical direction.

(Other embodiments)
The technique disclosed in this specification can be variously modified and implemented without any limitation on the embodiment for carrying out the disclosed technique. The disclosed techniques are not limited to the combinations shown in the embodiments and can be implemented in various combinations. The embodiments can have additional parts. The portion of the embodiment may be omitted. The portion of the embodiment can be replaced or combined with the portion of another embodiment. The structure, action, and effect of the embodiments are merely examples. The technical scope of the disclosed technology is not limited to the description of embodiments. Some technical scopes of the disclosed technology are indicated by the description of the scope of claims and should be understood to include all modifications within the meaning and scope equivalent to the description of the scope of claims. ..

In the above embodiment, the passive device as the energy output unit is the cooler 40, but the present invention is not limited to this. The passive device may output anything other than acoustic energy. For example, a passive device may be used as a heat pump to output heat. Further, for example, a passive device may be used as a generator to output electric energy.

Further, in the first embodiment described above, the supply unit 50 supplies the liquid phase condensable fluid 12B to the upper end portion of the stack 31, and in the fourth embodiment, the supply unit 50 supplies the liquid phase condensable fluid 12B to the stack 31. It was supplied to the hot end, but is not limited to this. The liquid-phase condensable fluid may be supplied so as to be distributed throughout the stack. For example, a liquid-phase condensing fluid may be supplied to the central portion of the stack in the sound wave traveling direction.

Further, in the first and fourth embodiments, the supply unit pumps the liquid phase condensable fluid and supplies it to the stack, and in the second and third embodiments, the supply unit heats the liquid phase condensable fluid. The condensable fluid that became the gas phase was supplied to the stack, but the present invention is not limited to this. The supply unit may have both a pumping function of the liquid-phase condensing fluid and a heating function of the liquid-phase condensing fluid.

Further, in the above embodiment, the inclined surface 24 is provided by an inclined pipe in which the pipe itself is inclined, but the present invention is not limited to this. An inclined surface may be provided on a part of the pipe member extending in the horizontal direction. Further, the liquid guide portion is not limited to the one in which an inclined surface is provided on at least a part of the pipe member. For example, a liquid guide tube that is attached to the tube member along the tube member and is separate from the tube member may be adopted.

Further, in the above embodiment, the supply unit supplies the condensable fluid to the stack 31 of the prime mover, but the present invention is not limited to this. For example, the supply unit may supply the condensable fluid to the stack 41 of the passive machine.

Further, in the above embodiment, the tube member 20 is a so-called double loop type thermoacoustic engine having a first loop tube 21 and a second loop tube 22, but the present invention is not limited to this. For example, one loop tube may be provided with a sound wave generating unit and an output unit. Further, for example, a sound wave generating section may be provided in the loop tube section, and an output section may be provided in the straight tube section as a resonance tube connected to the sound wave generating section. Further, for example, a sound wave generating unit and an output unit may be provided on a straight pipe having no loop pipe portion.

Further, in the above embodiment, the thermoacoustic engine has been applied to an air conditioner for a vehicle, but the present invention is not limited to this. For example, it may be applied to a stationary air conditioner.

1 Thermoacoustic engine 10 Working fluid 11 Non-condensable fluid 12 Condensable fluid 20 Tube member 24 Inclined surface (condensation part)
25 Liquid storage unit 31 Stack 32 High temperature side heat exchanger (heat absorber)
33 Low temperature side heat exchanger (radiator)
50 Supply unit 250 Electric heater (supply unit)
350 Peltier element (supply part)

Claims (7)

A pipe member (20) in which a working fluid (10), which is a mixture of a non-condensable fluid (11) and a condensable fluid (12), is filled therein to form a sound wave transmission path of the working fluid in the gas phase. When,
A heat absorber (32) provided on the pipe member to absorb heat from the outside to the working fluid, and
A radiator (33) provided on the pipe member and radiating heat from the working fluid to the outside,
A stack (31) provided on the tube member, sandwiched between the heat absorber and the radiator, and performing energy conversion between thermal energy and acoustic energy of sound waves by a thermoacoustic effect.
A liquid storage unit (25) provided on the pipe member for storing the condensable fluid in the liquid phase, and
A liquid guide section (24) provided on the pipe member and guiding the condensable fluid, which has become the liquid phase in the transmission path, to the liquid storage section.
Supply units (50, 250, 350) that supply the condensable fluid of the liquid phase stored in the liquid storage unit to the stack, and
With
The supply unit is a thermoacoustic engine having a temperature control device (250, 350) for heating and adjusting the temperature of the condensable fluid of the liquid phase stored in the liquid storage unit. The thermoacoustic engine according to claim 1, wherein the supply unit has a pump device (52) for pumping the condensable fluid of the liquid phase stored in the liquid storage unit to the stack. The temperature control device (350) has a heating mode for heating the condensable fluid of the liquid phase stored in the liquid storage unit and cooling the condensable fluid of the liquid phase stored in the liquid storage unit. The thermoacoustic engine according to claim 1 or 2, wherein the cooling mode for adjusting the temperature can be switched. Claims 1 to 3 include the liquid guide portion, which is formed so as to face the transmission path on the lower side of the transmission path and has an inclined surface (24) which is gradually positioned downward as it approaches the liquid storage portion. The thermoacoustic engine according to any one of the above. A pipe member (20) in which a working fluid (10), which is a mixture of a non-condensable fluid (11) and a condensable fluid (12), is filled therein to form a sound wave transmission path of the working fluid in the gas phase. When,
A heat absorber (32) provided on the pipe member to absorb heat from the outside to the working fluid, and
A radiator (33) provided on the pipe member and radiating heat from the working fluid to the outside,
A stack (31) provided on the tube member, sandwiched between the heat absorber and the radiator, and performing energy conversion between thermal energy and acoustic energy of sound waves by a thermoacoustic effect.
A liquid storage unit (25) provided on the pipe member for storing the condensable fluid in the liquid phase, and
A liquid guide section (24) provided on the pipe member and guiding the condensable fluid, which has become the liquid phase in the transmission path, to the liquid storage section.
Supply units (50, 250, 350) that supply the condensable fluid of the liquid phase stored in the liquid storage unit to the stack, and
With
The thermoacoustic engine having an inclined surface (24) formed so as to face the transmission path on the lower side of the transmission path and gradually positioned downward as it approaches the liquid storage section. The thermoacoustic engine according to claim 5, wherein the supply unit has a pump device (52) for pumping the condensable fluid of the liquid phase stored in the liquid storage unit to the stack. According to claim 4, the inclined surface is formed in at least a part of the pipe member, and is provided by an inclined pipe (23, 212, 222, 22) which is gradually positioned downward as it approaches the liquid storage portion. Item 6. The thermoacoustic engine according to any one of items 6.

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