CN110701011A - Thermoacoustic engine and thermoacoustic heating method - Google Patents

Abstract

The invention relates to the technical field of thermoacoustic heating equipment, in particular to a thermoacoustic engine. The main water cooler, regenerator and high temperature heat exchanger in the thermoacoustic engine are connected in sequence, and the shell of the high temperature heat exchanger has a built-in nuclear fuel stack, so that the working gas of self-oscillation in the engine is directly exchanged with the nuclear fuel stack It converts the heat of the nuclear fuel reactor into mechanical energy or transfers it to the environment, so that the nuclear fuel reactor can be effectively cooled to form a passive gas-cooled reactor, which can improve the safety of the nuclear reactor; The direct coupling heat exchange of the acoustic engine makes the external combustion thermoacoustic engine into a form of quasi-internal combustion engine, which greatly simplifies the system heat exchange process, the system power density can be greatly improved, and the pressure bearing wall of the thermoacoustic engine is not stable. If it needs to withstand high temperature, the internal working medium can work at a higher temperature, and the potential thermal performance will also be greatly improved.

Description

A thermoacoustic engine and thermoacoustic heating method

technical field

The invention relates to the technical field of thermoacoustic heating equipment, in particular to a thermoacoustic engine and a thermoacoustic heating method.

Background technique

A thermoacoustic engine is a sound wave generator that utilizes the thermoacoustic effect to convert thermal energy into sound energy to achieve sound power output. The thermoacoustic effect is a physical phenomenon in which the acoustic self-oscillation is caused by heat in an elastic medium (usually a high-pressure noble gas). The conversion of heat into pressure fluctuations can be achieved by utilizing the thermoacoustic phenomenon that heat generates self-excited oscillations in a pressurized gas. The pressure wave is the alternating mechanical energy, which realizes the heat-mechanical conversion. A thermoacoustic engine refers to a device that generates mechanical power from heat through the thermoacoustic effect, and its input heat is provided by a heater. The high temperature heater of the thermoacoustic engine is one of the core components of the thermoacoustic engine, which transfers the time-averaged heat from the external heat source to the inert gas working medium.

Nuclear energy (or atomic energy) is the energy released from the nucleus of an atom through a nuclear reaction, in accordance with Albert Einstein's mass-energy equation. Nuclear fuel refers to materials that can generate practical nuclear energy through nuclear fission or fusion in a nuclear reactor. The nuclear fuel body is a uranium dioxide ceramic pellet sintered from uranium mixture powder. The ceramic pellet is usually a cylinder. Hundreds of pellets are stacked together into a sleeve made of slender zirconium alloy material, so that the nuclear fuel A nuclear reaction takes place inside the casing, and since the nuclear reaction is like burning atoms, the structure is called a fuel rod.

Since the energy produced by nuclear fuel when reacting in a nuclear reactor is much greater than that of fossil fuels, the nuclear fuel in the nuclear fuel body will generate a lot of heat when it reacts. In order to prevent the reactor from being burnt due to overheating, circulating water (or other substances) must be used to take away a large amount of heat energy generated by the chain reaction, and the exported heat can turn water into water vapor and exchange heat with other working fluids, and finally Convert nuclear energy into other energy. The cooling of the existing nuclear fuel body is usually carried out by water cooling (including sodium cooling and air cooling), and the heat is indirectly transferred to the outside world. Although this method is mature in technology, the quality of heat transfer is low and the heat transfer process is complicated. , the system is huge.

At present, in the existing thermoacoustic engine, when the heat is transferred from the external heat source to the working gas in the thermoacoustic engine through the wall surface, the engine casing as the heat exchange wall surface must withstand high temperature and high pressure at the same time, because the maximum heat exchange temperature is affected by the material properties. The limitation makes the thermal conversion efficiency of the thermoacoustic engine also greatly limited. In addition, since the heat needs to be introduced into the engine through the wall of the heat exchanger, the external combustion thermoacoustic engine is usually large in size and low in power density, which is not conducive to practical applications.

SUMMARY OF THE INVENTION

(1) Technical problems to be solved

The technical problem to be solved by the present invention is to solve the problem that in the existing thermoacoustic engine, when the heat is transmitted from the external heat source to the working gas in the thermoacoustic engine through the wall surface, the engine casing as the heat exchange wall surface must withstand high temperature and high pressure at the same time. The thermal conversion efficiency of the engine is limited by the maximum heat exchange temperature that the material can withstand, as well as the problems of the large volume and low power density of the external combustion thermoacoustic engine, which are not conducive to practical applications.

(2) Technical solutions

In order to solve the above technical problems, the present invention provides a thermoacoustic engine, comprising a main water cooler, a regenerator and a high temperature heat exchanger which are connected in sequence, wherein a nuclear fuel stack is built in the shell of the high temperature heat exchanger, and the The nuclear fuel reactor is used to provide a place for the nuclear fuel utilization reaction, and heat exchange is performed between the nuclear fuel reactor and the working gas flowing through the high temperature heat exchanger, so as to increase the temperature of the working gas.

Preferably, the high-temperature heat exchanger further includes at least one control rod, each of which is inserted into the nuclear fuel stack and/or distributed around the nuclear fuel stack, each of the control rods Both are used to control the speed of the nuclear fuel reaction in the nuclear fuel reactor.

Preferably, the nuclear fuel reactor is provided with a porous structure, the porous structure is composed of nuclear fuel, and can form at least one axial gas flow channel in the nuclear fuel reactor, and the gas flow channel can be inserted into each of the gas flow channels. Control rods; the working gas flows in each of the gas flow channels, so that the working gas can exchange heat with at least one of the nuclear fuel reactors when flowing through the gas flow channels. .

Preferably, the porous structure includes:

A plurality of nuclear fuel rods arranged in the axial direction, each of the nuclear fuel rods is evenly juxtaposed in the shell of the high temperature heat exchanger; and/or

A plurality of nuclear fuel spheres, each of which is stacked within the housing.

Preferably, the gas flow channels are respectively left between the adjacent n nuclear fuel rods or the nuclear fuel balls (n≥3), and between the porous structure and the pressure-bearing inner wall of the nuclear fuel reactor, and each The control rods can be inserted into the air flow channels between the adjacent n nuclear fuel stacks (n≥3).

Preferably, the gas flow channel runs through the axis of the nuclear fuel rod.

Preferably, the cross section of the control rod is smaller than the cross section of the gas flow channel, so that when the control rod is inserted into the gas flow channel, a gap is left between the control rod and the gas flow channel for the working gas to pass through .

Preferably, when the porous structure is a plurality of nuclear fuel spheres, the plurality of the nuclear fuel spheres are stacked in several layers in the axial direction, and the plurality of the control rods are respectively inserted between the nuclear fuel spheres.

Preferably, the high-temperature heat exchanger further includes a plurality of heat-conducting fins, each of the heat-conducting fins is juxtaposed in the casing, and the gas is left between every two adjacent heat-conducting fins a flow channel; a plurality of the nuclear fuel stacks and a plurality of the control rods are respectively penetrated in each of the heat conducting fins.

Preferably, a gas flow channel runs through the axis of the nuclear fuel rod, so that the control rod can be inserted into the gas flow channel.

(3) Beneficial effects

The above-mentioned technical scheme of the present invention has the following beneficial effects:

1. In the thermoacoustic engine and the thermoacoustic heating method of the present invention, the main water cooler, the regenerator and the high temperature heat exchanger are connected in sequence, and the shell of the high temperature heat exchanger has a built-in nuclear fuel stack, thereby making the engine self-excited oscillation. The working gas directly exchanges heat with the nuclear fuel reactor, converts the heat of the nuclear fuel reactor into mechanical energy or transfers it to the environment, so that the nuclear fuel reactor can be effectively cooled, forming a passive gas-cooled reactor, which can improve the safety of the nuclear reactor. At the same time, the direct coupling heat exchange between the nuclear fuel reactor and the thermoacoustic engine turns the external combustion thermoacoustic engine into a form of quasi-internal combustion engine, which greatly simplifies the system heat exchange, and the system power density can be greatly improved;

2. Since the high-temperature heat exchanger is built into the thermoacoustic engine, the inner wall of the high-temperature heat exchanger, which is part of the engine shell, is the pressure-bearing wall. Since the working gas in the engine can directly exchange heat with the nuclear fuel reactor, The pressure-bearing wall is no longer subjected to high temperature, and even temperature-controlled cooling can be performed on the outer surface of the pressure-bearing wall. Compared with the existing technology, the outer surface of the engine casing and the pressure-bearing wall are changed from the original high temperature and high pressure environment to only need Withstand high pressure environment, enhance system security and stability;

3. In the high temperature heat exchanger, the degree of nuclear reaction is controlled by the contact degree between the control rod and the nuclear fuel reactor, and then the heating power and temperature are controlled, so that nuclear energy can be controllably applied to the thermoacoustic engine;

4. The thermoacoustic engine with the above structure further reduces the overall volume and makes the structure more compact and compact.

Description of drawings

1 is a schematic structural diagram of a thermoacoustic engine according to an embodiment of the present invention;

2 is a schematic structural diagram of a cross-section of a high-temperature heat exchanger according to Embodiment 1 of the present invention;

3 is a schematic structural diagram of a cross section of a high temperature heat exchanger according to Embodiment 2 of the present invention;

4 is a schematic structural diagram of a cross section of a high temperature heat exchanger according to Embodiment 3 of the present invention;

5 is a schematic structural diagram of a high temperature heat exchanger according to Embodiment 4 of the present invention;

FIG. 6 is a schematic structural diagram of a high temperature heat exchanger according to Embodiment 5 of the present invention.

Among them, 1. Main water cooler; 2. Regenerator; 3. Nuclear fuel rod; 4. Pressure bearing inner wall; 5. Control rod; 6. Gas flow channel;

Detailed ways

The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are intended to illustrate the present invention, but not to limit the scope of the present invention.

In the description of the present invention, unless otherwise specified, "plurality" means two or more; unless otherwise specified, "notch-shaped" means a shape other than a flat cross-section. The terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail" etc. refer to the orientation or positional relationship as Based on the orientation or positional relationship shown in the drawings, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood to limit the present invention. Furthermore, the terms "first," "second," "third," etc. are used for descriptive purposes only and should not be construed to indicate or imply relative importance.

In the description of the present invention, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense, unless otherwise expressly specified and limited, for example, it may be a fixed connection or a detachable connection Connection, or integral connection; it can be mechanical connection or electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific situations.

As shown in FIG. 1 , this embodiment provides a thermoacoustic engine, which includes a main water cooler 1 , a regenerator 2 and a high temperature heat exchanger connected in sequence, and the shell of the high temperature heat exchanger has a built-in In the nuclear fuel reactor, when the working gas enters the thermoacoustic engine, it sequentially flows through the main water cooler 1, the regenerator 2, and the nuclear fuel reactor in the high temperature heat exchanger. The working gas in the high-temperature heat exchanger conducts heat exchange to heat the working gas. During this process, the system spontaneously converts part of the heat of the high-temperature heat source into mechanical energy in the form of sound waves, and part of it is transferred to the environment through the low-temperature components. The inner wall of the shell of the high temperature heat exchanger is the pressure-bearing inner wall 4 .

Because in a thermoacoustic engine, as long as there is a high temperature heat source (that is, a temperature gradient is generated), the system will self-oscillate, that is, the system spontaneously converts part of the heat of the high temperature heat source into mechanical energy in the form of acoustic waves, and part of it is transmitted to the environment through low temperature components. Using this characteristic, the nuclear reactor can be set up in the thermoacoustic engine, so as to construct the high temperature heat exchanger in the thermoacoustic engine, and the self-oscillating working medium helium in the engine is used as the working gas to directly exchange heat with the nuclear reactor, and the The heat of the nuclear reactor is converted into mechanical energy or transferred to the environment, so that the nuclear reactor can be effectively cooled to form a passive gas-cooled reactor, thereby improving the safety of the nuclear reactor. The direct coupling heat exchange between the nuclear reactor and the thermoacoustic engine makes the external combustion thermoacoustic engine into a form of quasi-internal combustion engine, which greatly simplifies the system heat exchange, and the system power density can be greatly improved. The pressure wall surface no longer needs to withstand high temperature, the internal working medium can work at a higher temperature, and the potential thermal performance will also be greatly improved.

In the thermoacoustic engine of this embodiment, the high-temperature heat exchanger is built in the engine, and the high-temperature heat exchanger utilizes the reaction of nuclear fuel to directly contact the working gas flowing through the airflow channel to achieve heat exchange, so as to heat the working gas, thereby The working gas is directly heated inside the engine, and there is no need to set an additional heat exchange working medium outside the engine, which simplifies the energy transfer link, avoids the indirect heat transfer, and enhances the heat exchange effect, thereby greatly reducing the heat. loss, and greatly increase the heating power and heating temperature of the heater.

At the same time, since the high-temperature heat exchanger is built into the thermoacoustic engine, the pressure-bearing wall is the engine casing. Since the working gas in the engine can directly exchange heat with the nuclear fuel reactor, the pressure-bearing wall can no longer bear the high temperature, and even can Temperature-controlled cooling is performed on the outer surface of the pressure-bearing wall. Compared with the prior art, the outer shell and pressure-bearing wall of the airflow channel are changed from the original high temperature and high pressure environment to only need to withstand the high pressure environment, which enhances the safety and stability of the system.

More importantly, the working gas directly exchanges heat between the inside of the engine and the high-temperature heat exchanger, so that the working gas directly causes the high-temperature heat exchanger to release heat and cool down by heating up and absorbing heat, and a water-cooling mechanism can be set separately on the engine casing. , to assist the temperature-controlled cooling of the nuclear fuel rods 3, and further improve the heat transfer coefficient, energy utilization rate, safety and stability.

Specifically, the high-temperature heat exchanger includes a nuclear fuel stack and a gas flow channel 6, a plurality of nuclear fuel stacks are arranged in the gas flow channel according to a certain structure, and a working gas flows in the gas flow channel 6, so that the working gas flows through each gas flow When the channel 6 is used, heat exchange can be performed with at least one nuclear fuel reactor respectively.

In order to reliably control the reaction of the nuclear fuel reactor, preferably the high-temperature heat exchanger further comprises at least one control rod 5, each control rod 5 is respectively inserted in the nuclear fuel reactor and/or distributed around the nuclear fuel reactor. 5 are used to control the speed of the nuclear fuel reaction in the nuclear fuel reactor. The control rods 5 can be inserted into the nuclear fuel reactor or placed around the fuel reactor. The number of control rods 5 can be based on the size of the thermoacoustic engine and the degree of control of the reaction. make adjustments.

In this embodiment, it is preferable that the nuclear fuel reactor is provided with a porous structure, the porous structure is composed of nuclear fuel, and at least one axial gas flow channel 6 can be formed in the nuclear fuel reactor, and each gas flow channel 6 can be inserted into the control rod 5; Working gas flows in each gas flow channel 6, so that when the working gas flows through each gas flow channel 6, heat exchange can be performed with at least one nuclear fuel reactor.

It should be noted that the size, shape and arrangement order of each unit constituting the nuclear fuel reactor with the porous structure can be adjusted according to the heating power and the heating temperature. Preferably, the composition of the porous structure includes uniformly arranged nuclear fuel rods 3 and/or uniformly stacked nuclear fuel balls 8. When the porous structure is the uniformly arranged nuclear fuel rods 3, the porous structure is composed of a plurality of nuclear fuel rods arranged in the axial direction. The rods 3 are juxtaposed, and each nuclear fuel rod 3 is evenly juxtaposed in the shell of the high temperature heat exchanger; when the porous structure is uniformly stacked nuclear fuel balls 8, a plurality of nuclear fuel balls 8 are stacked in the shell.

Preferably, when the porous structure is a plurality of nuclear fuel rods 3 arranged in the axial direction, the arrangement order of the plurality of nuclear fuel rods 3 is sequential or inserted. The axes of each row of the nuclear fuel rods 3 are on the same straight line; when the arrangement sequence of a plurality of nuclear fuel rods 3 is the insertion row, the axes of the nuclear fuel rods 3 in two adjacent rows are staggered, and the two adjacent rows of nuclear fuel rods The distances between the axes of the rods 3 are equal. Similarly, when the porous structure is a plurality of nuclear fuel balls 8 , the plurality of nuclear fuel balls 8 are densely stacked in several layers in the axial direction, and a plurality of control rods 5 are respectively interspersed between the nuclear fuel balls 8 . According to the arrangement order of the nuclear fuel reactor, the arrangement order of the control rods 5 can be adjusted accordingly.

In this embodiment, the degree of contact between the control rod 5 and the nuclear fuel reactor can be adjusted as required, so as to control the degree of reaction of the nuclear fuel reactor, thereby controlling the heating power and the heating temperature. Preferably, gas flow channels 6 are left between adjacent n nuclear fuel rods 3 or nuclear fuel balls 8 (n≥3), and between the porous structure and the pressure-bearing inner wall 4 of the nuclear fuel reactor, and each adjacent n nuclear fuel Control rods 5 can be inserted into the airflow channels between stacks (n≥3).

At the same time, preferably a gas flow channel 6 runs through the axis of each nuclear fuel rod 3, so that a part of the working gas flows through the nuclear fuel stack from the axial pores, and the other part flows through the nuclear fuel stack from the gas flow channel to enhance heat exchange. effect and reduce resistance to gas flow. Further, in order to avoid obstructing the gas flow, it is preferable to make the cross section of the control rod 5 smaller than the cross section of the gas flow channel, so that when the control rod 5 is inserted into the gas flow channel 6, there is space between the control rod 5 and the gas flow channel 6 for working. In the gap through which the gas passes, when the control rod 5 is completely inserted into the gas flow channel, the gas flow can continue to flow in the gap to continue heat exchange, but the speed of the nuclear reaction is slowed down. Conversely, when the control rods 5 are completely pulled out of the nuclear fuel rods 3, the nuclear fuel rods 3 have the largest degree of reaction, so as to obtain the maximum and minimum degree of reaction, that is, to reliably control the speed of the internal reaction of the nuclear fuel reactor. When the control rods 5 are arranged around the nuclear fuel stack, the control strength of the control rods 5 can be enhanced.

In order to improve the structural stability, enhance the heat exchange effect, and reduce the gas flow resistance, it is preferable that the high temperature heat exchanger further includes a plurality of thermally conductive fins 7. and support; each heat-conducting fin 7 is juxtaposed in the casing, and the gas flow channel 6 is left between every two adjacent heat-conducting fins 7; a plurality of nuclear fuel stacks and a plurality of control rods 5 pass through respectively It is arranged in each heat conduction fin 7 to ensure that the internal structure of the high temperature heat exchanger is stable and reliable, and is not easily deformed; wherein, when there is a gas flow channel 6 running through the axis of the nuclear fuel rod 3, the control rod 5 can be inserted into the gas flow channel. 6 , so that the reaction of the nuclear fuel rods 3 can be controlled from the inside of the nuclear fuel rods 3 to control the heat exchange between the nuclear fuel rods 3 and the gas.

The above-mentioned thermoacoustic engine and thermoacoustic heating method will be described in detail below through five specific embodiments. The working gas is an inert gas such as helium gas, and the material of the control rod 5 is a material that is easy to absorb neutrons, such as boron and cadmium.

Example 1

In the thermoacoustic engine described in the first embodiment, the high-temperature heat exchanger is shown in Figure 2. The high-temperature heat exchanger mainly includes nuclear fuel rods 3, pressure-bearing inner walls 4 (ie, the shell of the high-temperature heat exchanger), and control rods. 5 and the gas flow channel 6. Among them, the plurality of nuclear fuel rods 3 are evenly arranged in the casing in the form of a row, and the gaps between the nuclear fuel rods 3 respectively form a plurality of gas flow channels 6, and the gas flow channels 6 in this part are respectively filled with There are control rods 5 for controlling nuclear reactions; there are also gaps between the nuclear fuel rods 3 arranged on the edge and the pressure-bearing inner wall 4, and these gaps also form a plurality of gas flow channels 6, all of which are axially penetrating Inside the high temperature heat exchanger, the helium gas that needs to be heated as the working gas passes through the gas flow channels 6 respectively, and conducts heat exchange with the nuclear fuel rods 3 respectively.

When the control rods 5 are all inserted into the gas flow channel 6, the reaction of the nuclear fuel rods 3 slows down; when the control rods 5 completely leave the gap, the reaction of the nuclear fuel rods 3 is the strongest, and the high temperature heat exchanger can provide the maximum heating power and heating temperature. Therefore, the degree of reaction progress can be controlled by controlling the depth of insertion of the control rod 5, thereby controlling the temperature of the helium gas.

Embodiment 2

The thermoacoustic engine described in the second embodiment can enhance the heat exchange effect and reduce the flow resistance. Specifically, the high-temperature heat exchanger of the second embodiment is shown in FIG. 3 , wherein the same parts of the high-temperature heat exchanger as those of the first embodiment will not be repeated, and the difference is that the nuclear fuel rods 3 described in the second embodiment are The shape has become a ring shape, that is, a gas flow channel 6 is provided through the axis of the nuclear fuel reactor, and the arrangement of the nuclear fuel rods 3 has changed from a straight row to a fork row, so that the internal structure of the high temperature heat exchanger becomes more for compactness and stability.

A plurality of nuclear fuel rods 3 are fixed at their respective positions in a fork row, and the gaps between each nuclear fuel rod 3 and the center of the annular nuclear fuel rod 3 are filled with control rods 5 for controlling the nuclear reaction, and the helium gas that needs to be heated flows from the fuel rods. The gas flow passages 6 at the annular centers of the nuclear fuel rods 3 and the gas flow passages 6 formed by the gaps between the nuclear fuel rods 3 pass through to obtain heat and cool the nuclear fuel stack.

Embodiment 3

The thermoacoustic engine described in the third embodiment can not only enhance the heat exchange effect, but also make it easier to control the degree of reaction. Specifically, the high-temperature heat exchanger of the third embodiment is shown in FIG. 4 , wherein the same parts of the high-temperature heat exchanger as those of the second embodiment will not be repeated, and the difference is: The cross-sectional shape has changed from a circle to a polygon, and a plurality of nuclear fuel rods 3 are juxtaposed into a honeycomb-like structure. The shape of the control rod 5 is still a cylindrical rod-like structure. Taking the nuclear fuel rod 3 with a hexagonal cross-section as an example, the control rod 5 can be inserted between the adjacent three hexagonal nuclear fuel rods 3, and the working gas passes between the nuclear fuel rods 3 and the gap between the nuclear fuel rod 3 and the control rod 5 and exchanges heat with the fuel rods.

When the control rods 5 are all inserted into the gaps between the hexagonal nuclear fuel rods 3, the control rods 5 absorb neutrons, control the reaction speed, and the nuclear reaction speed of the nuclear fuel reactor slows down; when the control rods 5 completely leave the space between the nuclear fuel rods 3 During the gap, the nuclear reaction between the nuclear fuel rods 3 is the most intense, and the high temperature heat exchanger can provide the maximum heating power and heating temperature at this time. Therefore, the degree of reaction progress can be controlled by adjusting the insertion depth of the control rod 5, and then the temperature of the helium gas can be controlled.

Embodiment 4

The thermoacoustic engine described in the fourth embodiment can further enhance the heat exchange efficiency and reduce the flow resistance. The high-temperature heat exchanger of the fourth embodiment is shown in FIG. 5 . The same parts of Example 2 and Example 3 will not be repeated, and the difference is that a plurality of thermally conductive fins 7 are inserted into the high-temperature heat exchanger described in Example 4.

Specifically, the plurality of heat-conducting fins 7 are arranged in sequence along the axial direction of the air flow channel, and all the annular nuclear fuel rods 3 and the control rods 5 vertically pass through each heat-conducting fin according to a certain arrangement (eg, in a row or a fork row). 7. In other words, the fin plates of each heat conduction fin 7 are parallel to the axis of the high temperature heat exchanger, and each nuclear fuel rod 3 and each control rod 5 are respectively perpendicular to the axis of the high temperature heat exchanger. The control rods 5 can be inserted into the gaps between the nuclear fuel stack and the heat-conducting fins 7 or into the annular nuclear fuel rods 3 . The helium gas passes through the gas flow passages 6 between the heat-conducting fins 7 and exchanges heat with the heat-conducting fins 7 and the nuclear fuel stack respectively, so as to transport the heat out.

When the control rods 5 are all inserted into the gaps between the nuclear fuel reactors, the reaction of the nuclear fuel reactors slows down, and the temperature of the helium gas gradually decreases; when the control rods 5 completely leave the above-mentioned gaps, the nuclear fuel reactors react the most strongly, and the high temperature The heat exchanger can provide the maximum heating power and heating temperature. Therefore, the degree of reaction of the nuclear fuel reactor can be controlled by controlling the depth of insertion of the control rod 5, thereby controlling the temperature of the helium gas.

Embodiment 5

In the thermoacoustic engine described in the fifth embodiment, the high-temperature heat exchanger is shown in FIG. 6 , and the parts of the high-temperature heat exchanger that are the same as those in any of the above-mentioned embodiments will not be repeated, and the difference is that the embodiment The nuclear fuel stack described in Section 5 is transformed from nuclear fuel rods 3 into nuclear fuel balls 8, which are stacked together according to a certain arrangement. The nuclear fuel ball 8 has a larger specific surface area than the nuclear fuel rod 3, so its heat exchange capacity is also better than that of the nuclear fuel rod 3, and the nuclear fuel ball 8 is of the order of millimeters, and has a metal sealing cladding on the ball surface to prevent the spread of nuclear pollution.

When the thermoacoustic engine works, the nuclear fuel spheres 8 react with each other, and the working gas quickly flows through the gas flow channel 6 reserved between the nuclear fuel spheres 8 and exchanges heat with the nuclear fuel spheres 8, thereby attracting The heat is heated up, and the nuclear fuel ball 8 is exothermic and cooled. The direction in which the control rods 5 are inserted into the nuclear reactor is perpendicular to the direction of the gas flow channel 6, and the control rods 5 are inserted into the gaps between the nuclear fuel balls 8 from around the pressure-bearing wall surface to slow down the reaction of the nuclear fuel reactor. The temperature of the helium gas at this time is decreasing gradually.

To sum up, in the thermoacoustic engine and the thermoacoustic heating method of this embodiment, first, the main water cooler 1 , the regenerator 2 and the high temperature heat exchanger are connected in sequence, and the shell of the high temperature heat exchanger has a built-in nuclear fuel reactor , so that the self-excited oscillating working gas in the engine directly exchanges heat with the nuclear fuel reactor, converts the heat of the nuclear fuel reactor into mechanical energy or transfers it to the environment, so that the nuclear fuel reactor can be effectively cooled, forming a passive gas-cooled reactor, The safety of the nuclear reactor can be improved; at the same time, the direct coupling heat exchange between the nuclear fuel reactor and the thermoacoustic engine turns the external combustion thermoacoustic engine into a form of quasi-internal combustion engine, which greatly simplifies the system heat exchange and reduces the power consumption of the system. The density can be greatly improved.

Secondly, since the high-temperature heat exchanger is built into the thermoacoustic engine, the inner wall of the high-temperature heat exchanger, which is part of the engine shell, is the pressure-bearing wall. Since the working gas in the engine can directly exchange heat with the nuclear fuel reactor, The pressure-bearing wall is no longer subjected to high temperature, and even temperature-controlled cooling can be performed on the outer surface of the pressure-bearing wall. Compared with the existing technology, the outer surface of the engine casing and the pressure-bearing wall are changed from the original high temperature and high pressure environment to only need Withstand high pressure environment, enhance system security and stability.

At the same time, in the high temperature heat exchanger, the degree of nuclear reaction is controlled by the contact degree between the control rod 5 and the nuclear fuel reactor, thereby controlling the heating power and temperature, so that nuclear energy can be controllably applied to the thermoacoustic engine;

In addition, the thermoacoustic engine with the above structure further reduces the overall volume, making the structure more miniaturized and compact.

The embodiments of the present invention are presented for purposes of illustration and description, and are not intended to be exhaustive or to limit the invention to the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiment was chosen and described in order to better explain the principles of the invention and the practical application, and to enable others of ordinary skill in the art to understand the invention for various embodiments with various modifications as are suited to the particular use.

Claims (9)

1. A thermoacoustic engine, characterized in that it comprises a main water cooler, a regenerator and a high-temperature heat exchanger that are communicated in sequence, and the shell of the high-temperature heat exchanger has a built-in nuclear fuel stack, and the nuclear fuel stack is used for Provide a place for nuclear fuel utilization reaction, heat exchange is performed between the nuclear fuel reactor and the working gas flowing through the high temperature heat exchanger, so as to make the working gas warm up; the high temperature heat exchanger also includes at least one control rod , each of the control rods is respectively inserted in the nuclear fuel reactor, and/or distributed around the nuclear fuel reactor, and each of the control rods is used to control the speed of the nuclear fuel reaction in the nuclear fuel reactor. . 2 . The thermoacoustic engine according to claim 1 , wherein the nuclear fuel stack is provided with a porous structure, the porous structure is composed of nuclear fuel, and can form at least one axial gas flow in the nuclear fuel stack. 3 . The control rod can be inserted into each of the gas flow channels; the working gas is circulated in each of the gas flow channels, so that when the working gas flows through each of the gas flow channels, Heat exchange is possible with at least one of the nuclear fuel stacks, respectively. 3. The thermoacoustic engine of claim 2, wherein the porous structure comprises: A plurality of nuclear fuel rods arranged in the axial direction, each of the nuclear fuel rods is evenly juxtaposed in the shell of the high temperature heat exchanger; and/or A plurality of nuclear fuel spheres, each of which is stacked within the housing. 4 . The thermoacoustic engine according to claim 3 , wherein the pressure between the adjacent n nuclear fuel rods or the nuclear fuel balls (n≧3), and the pressure between the porous structure and the nuclear fuel stack. 5 . The gas flow channels are respectively left between the inner walls, and the control rods can be inserted into the gas flow channels between every adjacent n of the nuclear fuel stacks (n≥3). 5 . The thermoacoustic engine according to claim 3 , wherein the gas flow channel runs through the axis of the nuclear fuel rod. 6 . 6 . The thermoacoustic engine according to claim 5 , wherein the cross section of the control rod is smaller than the cross section of the gas flow channel, so that when the control rod is inserted into the gas flow channel, the control rod is connected to the gas flow channel. 7 . A gap for the working gas to pass through is left between the flow channels. 7 . The thermoacoustic engine according to claim 3 , wherein when the porous structure is a plurality of nuclear fuel balls, the plurality of nuclear fuel balls are stacked in several layers in the axial direction, and a plurality of the control rods are respectively interspersed. 8 . between each of the nuclear fuel spheres. 8 . The thermoacoustic engine according to claim 3 , wherein the high-temperature heat exchanger further comprises a plurality of heat-conducting fins, and each of the heat-conducting fins is respectively juxtaposed in the casing, 9 . The gas flow channel is left between every two adjacent heat-conducting fins; a plurality of the nuclear fuel stacks and a plurality of the control rods are respectively penetrated in each of the heat-conducting fins. 9 . The thermoacoustic engine according to claim 8 , wherein a gas flow channel runs through the axis of the nuclear fuel rod, so that the control rod can be inserted into the gas flow channel. 10 .

Images