Liquid metal magnetohydrodynamic power generation system driven by two-stage loop traveling wave thermoacoustic engine

Abstract

The application provides a liquid metal magnetohydrodynamic power generation system driven by a two-stage loop traveling wave thermoacoustic engine, comprising a two-stage loop traveling wave thermoacoustic engine and a liquid metal magnetohydrodynamic generator set, wherein the two-stage loop traveling wave thermoacoustic engine comprises two thermoacoustic conversion units, the two thermoacoustic conversion units are connected in a head-to-tail mode to form a traveling wave loop, the liquid metal magnetohydrodynamic generator set comprises two liquid metal magnetohydrodynamic generators, each of the two liquid metal magnetohydrodynamic generators comprises liquid metal, the two liquid metal magnetohydrodynamic generators are arranged in the traveling wave loop, under the action of any one of the two thermoacoustic conversion units, the flow directions of the liquid metals in the two liquid metal magnetohydrodynamic generators are opposite, the vibrations generated by the movements of the liquid metals offset each other, thereby reducing the vibration of the power generation system and improving the stability of the power generation output performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of thermoacoustic power generation, and in particular to a two-stage loop traveling wave thermoacoustic engine driven liquid metal magnetohydrodynamic power generation system. BACKGROUND

[0002] A thermoacoustic engine is an energy conversion device that can convert heat energy into mechanical energy. Since it has no mechanical moving parts, it has the advantages of high reliability and long service life. Since it is an external combustion engine, it has the advantage of good energy adaptability, and can utilize various heat sources such as nuclear energy, solar energy, industrial waste heat, and biomass energy. According to the characteristics of the acoustic field in the thermoacoustic engine, the thermoacoustic engine can be divided into standing wave thermoacoustic engines and traveling wave thermoacoustic engines. Since the traveling wave thermoacoustic engine is based on a reversible thermodynamic cycle, it has a high potential thermal efficiency.

[0003] A magnetohydrodynamic generator is an electromechanical conversion device with no mechanical moving parts. It uses the Lorentz force experienced by moving charged particles in a magnetic field to convert the mechanical energy of the charged particles into electrical energy. The charged particles in the magnetohydrodynamic generator are generally positive and negative charges in a conductive fluid. Since the electrical conductivity of liquid metal is very high, there is no need for high-temperature ionization, and the operating temperature of the generator can be relatively low. Therefore, in the prior art, a magnetohydrodynamic generator using liquid metal as the working medium is commonly used.

[0004] Combining the above-mentioned thermoacoustic engine and liquid metal magnetohydrodynamic generator can form a completely mechanical moving part-free thermoelectric conversion device. This power generation device combines the advantages of the thermoacoustic engine and the liquid metal magnetohydrodynamic generator.

[0005] US4599551A discloses a thermoacoustic liquid metal magnetohydrodynamic power generation device, which uses an opposed standing wave thermoacoustic engine as a driving source. Since the standing wave thermoacoustic engine is based on an irreversible thermodynamic cycle, its potential efficiency is low, and the use of liquid metal fluid as the working medium in the thermoacoustic engine increases the design difficulty and manufacturing cost. Based on the above-mentioned shortcomings, CN101282074B proposes a corresponding improvement scheme, which uses a traveling wave thermoacoustic engine as a power source, and the working medium in the thermoacoustic engine is a gas, which relies on gravity or an elastic membrane to separate the working medium in the thermoacoustic engine and the liquid metal magnetohydrodynamic generator. However, the thermoacoustic engine used in this system is a traditional traveling wave thermoacoustic engine, which has a large volume and weight, and serious loss.

[0006] To this end, the patent CN106533119A proposes a further improved scheme, in which a single-stage loop traveling wave thermoacoustic engine is used as a power source, and a liquid metal MHD generator is placed in the resonant tube of the thermoacoustic engine, thereby improving the compactness of the system and reducing the loss in the resonant tube. The scheme overcomes the shortcomings of the systems proposed in US4599551A and CN101282074B, but still has the following defects: first, due to the asymmetric structure of the device, the system vibrates greatly during operation; second, the single-stage loop traveling wave thermoacoustic engine not only has small pressure fluctuations, but also has a high starting temperature; third, the output power of the single-stage loop traveling wave thermoacoustic engine is small, and the power generation power of the system is low. SUMMARY

[0007] The present application provides a two-stage loop traveling wave thermoacoustic engine driven liquid metal MHD power generation system to solve the problem of large vibration and low power generation power of the existing technology.

[0008] The present application provides a two-stage loop traveling wave thermoacoustic engine driven liquid metal MHD power generation system, comprising a two-stage loop traveling wave thermoacoustic engine and a liquid metal MHD generator set;

[0009] The two-stage loop traveling wave thermoacoustic engine comprises two thermoacoustic conversion units, and the two thermoacoustic conversion units are connected in series to form a traveling wave loop.

[0010] The liquid metal MHD generator set comprises two liquid metal MHD generators, and each of the two liquid metal MHD generators comprises liquid metal. The two liquid metal MHD generators are arranged in the traveling wave loop, and under the action of any one of the two thermoacoustic conversion units, the flow directions of the liquid metals in the two liquid metal MHD generators are opposite.

[0011] According to the two-stage loop traveling wave thermoacoustic engine driven liquid metal MHD power generation system provided by the present application, the thermoacoustic conversion unit comprises a main chamber temperature exchanger, a regenerator, a heater, a thermal buffer tube and a secondary chamber temperature exchanger, and the main chamber temperature exchanger, the regenerator, the heater, the thermal buffer tube and the secondary chamber temperature exchanger are connected in series.

[0012] According to the two-stage loop traveling wave thermoacoustic engine driven liquid metal MHD power generation system provided by the present application, the two-stage loop traveling wave thermoacoustic engine further comprises a resonant tube, wherein the main chamber temperature exchanger of one of the thermoacoustic conversion units is connected to the secondary chamber temperature exchanger of the other thermoacoustic conversion unit through the resonant tube; and the secondary chamber temperature exchanger of one of the thermoacoustic conversion units is connected to the main chamber temperature exchanger of the other thermoacoustic conversion unit through the resonant tube.

[0013] The liquid metal MHD power generation system driven by the two-stage loop traveling wave thermoacoustic engine according to the present application further comprises cavities, which are arranged in the resonant tubes and communicate with the resonant tubes.

[0014] The liquid metal MHD power generation system driven by the two-stage loop traveling wave thermoacoustic engine according to the present application, wherein the resonant tubes comprise a first resonant tube, a second resonant tube, a third resonant tube and a fourth resonant tube.

[0015] The primary chamber temperature exchanger of one of the thermoacoustic conversion units is connected to one end of one of the cavities through the first resonant tube, and the secondary chamber temperature exchanger of the other thermoacoustic conversion unit is connected to the other end of the cavity through the second resonant tube.

[0016] The secondary chamber temperature exchanger of one of the thermoacoustic conversion units is connected to one end of the other cavity through the third resonant tube, and the primary chamber temperature exchanger of the other thermoacoustic conversion unit is connected to the other end of the other cavity through the fourth resonant tube.

[0017] The liquid metal MHD power generation system driven by the two-stage loop traveling wave thermoacoustic engine according to the present application further comprises DC suppressors, which are arranged at the end of the first resonant tube close to the primary chamber temperature exchanger and the end of the fourth resonant tube close to the primary chamber temperature exchanger.

[0018] The liquid metal MHD power generation system driven by the two-stage loop traveling wave thermoacoustic engine according to the present application, wherein the two liquid metal MHD generators are arranged in opposition or in parallel between the two thermoacoustic conversion units.

[0019] The liquid metal MHD power generation system driven by the two-stage loop traveling wave thermoacoustic engine according to the present application, wherein in the case of the two liquid metal MHD generators arranged in opposition, the first ends of the two liquid metal MHD generators are connected to the second resonant tube, and the second ends of the two liquid metal MHD generators are connected to the third resonant tube.

[0020] The liquid metal MHD power generation system driven by the two-stage loop traveling wave thermoacoustic engine according to the present application, wherein in the case of the two liquid metal MHD generators arranged in opposition, the first ends of the two liquid metal MHD generators are connected to the first resonant tube, and the second ends of the two liquid metal MHD generators are connected to the fourth resonant tube.

[0021] The two-stage loop traveling wave thermoacoustic engine driven liquid metal magnetohydrodynamic power generation system provided by the application is characterized in that: in the case that two liquid metal magnetohydrodynamic generators are arranged side by side, the first end and the second end of one of the liquid metal magnetohydrodynamic generators are connected to the first resonant tube and the fourth resonant tube respectively; and the first end and the second end of the other liquid metal magnetohydrodynamic generator are connected to the second resonant tube and the third resonant tube respectively.

[0022] The two-stage loop traveling wave thermoacoustic engine driven liquid metal magnetohydrodynamic power generation system provided by the application is characterized in that: in the case that two liquid metal magnetohydrodynamic generators are arranged side by side, the first end and the second end of one of the liquid metal magnetohydrodynamic generators are connected to the first resonant tube and the fourth resonant tube respectively; and the first end and the second end of the other liquid metal magnetohydrodynamic generator are connected to the second resonant tube and the third resonant tube respectively. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0024] Figure 1 is one of the structural schematic diagrams of the two-stage loop traveling wave thermoacoustic engine driven liquid metal magnetohydrodynamic power generation system provided by the application;

[0025] Figure 2 is one of the structural schematic diagrams of the two-stage loop traveling wave thermoacoustic engine driven liquid metal magnetohydrodynamic power generation system provided by the application;

[0026] Reference signs:

[0027] 1: two-stage loop traveling wave thermoacoustic engine; 11: first thermoacoustic conversion unit; 111: main chamber temperature exchanger; 112: regenerator; 113: heater; 114: thermal buffer tube; 115: secondary chamber temperature exchanger; 12: second thermoacoustic conversion unit; 13: resonator; 131: first resonator; 132: second resonator; 133: third resonator; 134: fourth resonator; 14: cavity; 15: DC suppressor; 2: liquid metal MHD generator set; 21: first liquid metal MHD generator; 22: second liquid metal MHD generator; 3: connecting pipe. DETAILED DESCRIPTION

[0028] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be clearly and completely described below with reference to the drawings in the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0029] In the description of the embodiments of the present application, it should be noted that the terms "left", "right", "top", "bottom", and the like indicate the orientation or positional relationship shown in the drawings based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0030] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "provided with", "connected", "provided in" and the like should be understood broadly, for example, "connected" can be fixedly connected, or detachably connected, or integrally connected; can be mechanically connected, or electrically connected; can be directly connected, or indirectly connected through an intermediate medium, or can be the communication between two elements inside. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0031] The technical solutions of the present application will be described below in combination with Figure 1 and Figure 2 a two-stage loop traveling wave thermoacoustic engine driven liquid metal MHD power generation system.

[0032] The embodiments of the present application provide a two-stage loop traveling wave thermoacoustic engine driven liquid metal MHD power generation system, comprising: a two-stage loop traveling wave thermoacoustic engine 1 and a liquid metal MHD generator set 2.

[0033] The two-stage loop traveling wave thermoacoustic engine 1 comprises two thermoacoustic conversion units connected head to tail to form a traveling wave loop.

[0034] The liquid metal MHD generator set 2 comprises two liquid metal MHD generators, each comprising liquid metal, and arranged in the traveling wave loop.

[0035] Specifically, for the convenience of introducing the present embodiment, in the following introduction, the two thermoacoustic conversion units are defined as the first thermoacoustic conversion unit 11 and the second thermoacoustic conversion unit 12, and the two liquid metal MHD generators are defined as the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22.

[0036] In consideration of the stability of the overall system and the maximum optimization of the damping effect, the first thermoacoustic conversion unit 11 and the second thermoacoustic conversion unit 12 are preferably of the same structure, and the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are also preferably of the same structure.

[0037] As shown in FIG. 1, the first thermoacoustic conversion unit 11 and the second thermoacoustic conversion unit 12 are arranged in reverse 180 degrees, and connected head to tail through the resonant tube 13 to form a closed loop, thereby constituting a traveling wave loop. Figure 1

[0038] The first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are connected in parallel and then connected at symmetrical positions of the traveling wave loop through connecting pipes 3 on both sides, i.e., connected at the head and tail of the first thermoacoustic conversion unit 11 and the second thermoacoustic conversion unit 12, respectively. This arrangement not only effectively improves the stability of the structure, but also the liquid metals in the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 always move in opposite directions, so the vibrations generated by the movement of the liquid metals in the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 can be offset, thereby achieving the effect of damping.

[0039] In addition, the liquid metal MHD generator can be a conduction type MHD generator, which is composed of a neodymium iron boron permanent magnet, silicon steel, liquid metal, a copper electrode, a copper strip, a stainless steel channel, and an elastic film on both sides of the stainless steel channel.

[0040] ​The neodymium-iron-boron permanent magnet and silicon steel are used for providing a magnetic field for the liquid metal; the liquid metal is a low-melting-point metal or an alloy containing a low-melting-point metal, for example, a gallium-indium-tin alloy; the copper strip is used as a load of the power generation device to consume electric energy; the copper electrode is used for connecting the liquid metal and the copper strip; the stainless steel channel is used for containing the liquid metal, and an electrically insulating layer is sprayed on the inner side of the stainless steel channel; and the elastic membranes on the two sides of the stainless steel channel are used for separating the liquid metal and the gas working medium in the connecting pipe 3 at the two ends of the liquid metal magnetohydrodynamic generator.

[0041] The working principle of the liquid metal magnetohydrodynamic generator is as follows: when the liquid metal reciprocates in the axial direction in the magnetohydrodynamic channel, the liquid metal cuts the magnetic lines of force to generate an induced electromotive force, which can drive an external electric load and output electric energy.

[0042] The two-stage loop traveling wave thermoacoustic engine driven liquid metal magnetohydrodynamic power generation system provided by the embodiment of the present application is characterized in that: the two-stage loop traveling wave thermoacoustic engine is provided, two thermoacoustic conversion units in the two-stage loop traveling wave thermoacoustic engine are connected in a head-to-tail manner to form a traveling wave loop, the thermoacoustic conversion units are used for converting heat energy into mechanical energy of reciprocating oscillation of the gas working medium in the traveling wave loop, further, two liquid metal magnetohydrodynamic generators are arranged on the traveling wave loop, the mechanical energy generated by the two-stage loop traveling wave thermoacoustic engine is transmitted to the liquid metal magnetohydrodynamic generator set, and the reciprocating oscillation of the liquid metal in the two liquid metal magnetohydrodynamic generators is driven, so as to generate electric energy, in the process, the flow directions of the liquid metals in the two liquid metal magnetohydrodynamic generators are always opposite, so that the vibrations generated by the movements of the liquid metals in the two liquid metal magnetohydrodynamic generators can be offset, thereby reducing the vibration of the power generation system, and further, compared with the single-stage loop traveling wave thermoacoustic engine, the two-stage loop traveling wave thermoacoustic engine has higher energy density, lower starting temperature, and more stable power generation output performance, and can effectively improve the power generation power of the power generation system.

[0043] In the optional embodiment, the thermoacoustic conversion unit comprises a primary chamber temperature exchanger 111, a regenerator 112, a heater 113, a thermal buffer tube 114, and a secondary chamber temperature exchanger 115, and the primary chamber temperature exchanger 111, the regenerator 112, the heater 113, the thermal buffer tube 114, and the secondary chamber temperature exchanger 115 are sequentially connected in a head-to-tail manner.

[0044] Specifically, in order to ensure the overall symmetry and stability of the power generation system, the structure of the first thermoacoustic conversion unit 11 is the same as that of the second thermoacoustic conversion unit 12, as shown in the figure, both of the thermoacoustic conversion units are sequentially connected in a head-to-tail manner by the primary chamber temperature exchanger 111, the regenerator 112, the heater 113, the thermal buffer tube 114, and the secondary chamber temperature exchanger 115. Figure 1

[0045] ​By heating the heater 113 in the thermo-acoustic conversion unit and cooling the main chamber heat exchanger 111, an axial temperature gradient can be formed in the regenerator 112. When the axial temperature gradient is greater than the critical temperature gradient of the two-stage loop traveling wave thermo-acoustic engine 1, the gas working substance in the two-stage loop traveling wave thermo-acoustic engine 1 generates self-excited oscillation under the action of thermal energy, and further converts the thermal energy input by the heater 113 into acoustic energy (mechanical energy) of the reciprocating oscillation of the gas working substance.

[0046] In an optional embodiment, the two-stage loop traveling wave thermo-acoustic engine further comprises a resonant tube 13, wherein the main chamber heat exchanger 111 of one thermo-acoustic conversion unit is connected with the secondary chamber heat exchanger 115 of the other thermo-acoustic conversion unit through the resonant tube 13; and the secondary chamber heat exchanger 115 of one thermo-acoustic conversion unit is connected with the main chamber heat exchanger 111 of the other thermo-acoustic conversion unit through the resonant tube 13.

[0047] Specifically, as shown in Figure 1 the main chamber heat exchanger 111 of the first thermo-acoustic conversion unit 11 is connected with the secondary chamber heat exchanger 115 of the second thermo-acoustic conversion unit 12 through the resonant tube 13, and the secondary chamber heat exchanger 115 of the first thermo-acoustic conversion unit 11 is also connected with the main chamber heat exchanger 111 of the second thermo-acoustic conversion unit 12 through the resonant tube 13, thereby realizing the communication between the two thermo-acoustic conversion units and forming a closed loop.

[0048] The diameter, length and shape of the resonant tube 13 are not specifically limited and can be set according to actual needs.

[0049] In the process of converting thermal energy into acoustic energy, the gas in the resonant tube 13 can affect the acoustic sensitivity and further affect the resonant frequency. In actual operation, inert gases such as argon, helium, nitrogen and carbon dioxide can be applied to the thermo-acoustic conversion unit protected in the embodiments of the present application.

[0050] In an optional embodiment, the two-stage loop traveling wave thermo-acoustic engine further comprises a cavity, which is arranged in the resonant tube and communicates with the resonant tube.

[0051] Specifically, the two-stage loop traveling wave thermo-acoustic engine 1 further comprises two cavities 14, as shown in Figure 1 one cavity 14 is arranged on the resonant tube 13 between the main chamber heat exchanger 111 of the first thermo-acoustic conversion unit 11 and the secondary chamber heat exchanger 115 of the second thermo-acoustic conversion unit 12, and symmetrically, one cavity 14 is also arranged on the resonant tube 13 between the secondary chamber heat exchanger 115 of the first thermo-acoustic conversion unit 11 and the main chamber heat exchanger 111 of the second thermo-acoustic conversion unit 12. The two cavities 14 are symmetrically arranged, which can be beneficial to the balance of acoustic energy in the resonant tube 13, thereby promoting the balance of the whole system.

[0052] The purpose of the cavity 14 is to establish a suitable sound field, further enhance the resonance effect of the gas working substance, increase the traveling wave component in the resonant tube 13, increase the efficiency of converting thermal energy into acoustic energy, make the power generation output performance of the whole system more stable, and effectively improve the power generation power of the power generation system.

[0053] In an optional embodiment, the resonant tube 13 includes a first resonant tube 131, a second resonant tube 132, a third resonant tube 133, and a fourth resonant tube 134.

[0054] The primary chamber temperature exchanger 111 of one of the thermoacoustic conversion units is connected to one end of one of the cavities 14 through the first resonant tube 131, and the secondary chamber temperature exchanger 115 of the other thermoacoustic conversion unit is connected to the other end of the cavity through the second resonant tube 132.

[0055] The secondary chamber temperature exchanger 115 of one of the thermoacoustic conversion units is connected to one end of the other cavity through the third resonant tube 133, and the primary chamber temperature exchanger 111 of the other thermoacoustic conversion unit is connected to the other end of the other cavity through the fourth resonant tube 134.

[0056] Specifically, as shown in Figure 1 the primary chamber temperature exchanger 111 of the first thermoacoustic conversion unit 11 is in communication with the left cavity 14 through the first resonant tube 131, and the primary chamber temperature exchanger 111 of the second thermoacoustic conversion unit 12 arranged in the opposite direction is also in communication with the right cavity 14 through the fourth resonant tube 134; the secondary chamber temperature exchanger 115 of the first thermoacoustic conversion unit 11 is in communication with the right cavity 14 through the third resonant tube 133, and the secondary chamber temperature exchanger 115 of the second thermoacoustic conversion unit 12 arranged in the opposite direction is also in communication with the left cavity 14 through the second resonant tube 132.

[0057] The structures of the four resonant tubes 13 can be the same or different. Considering that the sound fields in the primary chamber temperature exchangers 111 and the secondary chamber temperature exchangers 115 connected respectively are different, the resonant tubes 13 connected correspondingly are also different. Therefore, the first resonant tube 131 and the fourth resonant tube 134 are preferably of the same structure, and the second resonant tube 132 and the third resonant tube 133 are preferably of the same structure. The specific structural parameters, such as the length and diameter of the resonant tube 13, are not specifically limited, and are made according to actual needs to meet the sound field adjustment requirements.

[0058] In an optional embodiment, the two-stage loop traveling wave thermoacoustic engine 1 further includes a direct current suppressor 15, and two direct current suppressors 15 are respectively arranged at one end of the first resonant tube 131 close to the primary chamber temperature exchanger 111 and one end of the fourth resonant tube 134 close to the primary chamber temperature exchanger 111.

[0059] Specifically, as shown in Figure 1As shown, a straight flow inhibitor 15 is arranged at the connection between the first resonant pipe 131 and the main chamber temperature exchanger 111 of the first thermoacoustic conversion unit 11, and a straight flow inhibitor 15 is also arranged at the connection between the fourth resonant pipe 134 and the main chamber temperature exchanger 111 of the second thermoacoustic conversion unit 12. In the embodiment of the present application, the straight flow inhibitor 15 can be an elastic film or an asymmetric jet pump, which functions to inhibit the acoustic straight flow in the thermoacoustic loop, guarantee the normal operation of the two-stage loop traveling wave thermoacoustic engine 1, and improve the thermal energy utilization rate of the two-stage loop traveling wave thermoacoustic engine 1.

[0060] In an optional embodiment, the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are arranged in opposition or in parallel between the two thermoacoustic conversion units.

[0061] Specifically, in order to realize the 180-degree reverse movement of the metal liquid in the first liquid metal MHD generator 21 and the metal liquid in the second liquid metal MHD generator 22 driven by the pressure wave in the resonant pipe 13, the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 can be arranged in opposition as shown in Figure 1 As shown, the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are arranged in opposition between the two thermoacoustic conversion units through the connecting pipe 3, or can be arranged in parallel as shown in Figure 2 As shown, the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are arranged in parallel between the two thermoacoustic conversion units through the connecting pipe 3. In the two liquid metal MHD generators, the vibration caused by the movement of the liquid metal can be offset, thereby realizing the effect of vibration reduction.

[0062] In an optional embodiment, in the case of the two liquid metal MHD generators arranged in opposition, the first ends of the two liquid metal MHD generators are connected to the second resonant pipe 132, and the second ends of the two liquid metal MHD generators are connected to the third resonant pipe 133.

[0063] Specifically, as shown in Figure 1 As shown, the two liquid metal MHD generators are arranged in opposition, i.e., the first ends of the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are connected through the connecting pipe 3, the second ends of the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are connected through the connecting pipe 3, and the two liquid metal MHD generators connected in opposition are connected between the secondary chamber temperature exchangers 115 of the two thermoacoustic conversion units through the connecting pipe 3, i.e., the first ends of the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are connected to the second resonant pipe 132 through the connecting pipe 3, and the second ends of the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are connected to the third resonant pipe 133 through the connecting pipe 3.

[0064] Two liquid metal MHD generators can be arranged as shown in the left side, or arranged in the right side, as long as they are arranged symmetrically in the same side. Figure 1

[0065] In this way, when the sound wave reaches the liquid metal MHD generator, the paths are completely opposite, and the directions of the liquid metal movement driven by the sound wave are also completely opposite, so that the vibrations caused by the liquid metal movement in the two liquid metal MHD generators can be offset, thereby achieving the effect of vibration reduction.

[0066] In an optional embodiment, when the two liquid metal MHD generators are arranged opposite to each other, the first ends of the two liquid metal MHD generators are connected to the first resonant tube 131, and the second ends of the two liquid metal MHD generators are connected to the fourth resonant tube 134.

[0067] Specifically, as described above, the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are arranged opposite to each other, and can also be connected between the main chamber heat exchanger 111 of the two thermoacoustic conversion units through the connecting pipe 3, that is, the first ends of the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are connected to the first resonant tube 131 through the connecting pipe 3, and the second ends of the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are connected to the fourth resonant tube 134 through the connecting pipe 3.

[0068] In this way, when the sound wave reaches the liquid metal MHD generator, the paths are completely opposite, and the directions of the liquid metal movement driven by the sound wave are also completely opposite, so that the vibrations caused by the liquid metal movement in the two liquid metal MHD generators can be offset, thereby achieving the effect of vibration reduction.

[0069] In actual operation, the effect of converting heat energy into sound energy and converting sound energy into electric energy by this connection mode is not as good as the above connection mode, but it can also achieve a certain power generation effect and has a good vibration reduction effect, so this embodiment also falls within the protection scope of the present application.

[0070] In an optional embodiment, when the two liquid metal MHD generators are arranged side by side, the first end and the second end of one of the liquid metal MHD generators are connected to the first resonant tube 131 and the fourth resonant tube 134 respectively, and the first end and the second end of the other liquid metal MHD generator are connected to the second resonant tube 132 and the third resonant tube 133 respectively.

[0071] Specifically, as described above, the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are arranged opposite to each other, and can also be connected between the main chamber heat exchanger 111 of the two thermoacoustic conversion units through the connecting pipe 3, that is, the first ends of the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are connected to the first resonant tube 131 through the connecting pipe 3, and the second ends of the first liquid metal MHD generator 21 and the second liquid metal MHD generator 22 are connected to the fourth resonant tube 134 through the connecting pipe 3. Figure 2 ​As shown, the two liquid-metal MHD generators can be arranged side by side through the connecting pipe 3, the first end of the first liquid-metal MHD generator 21 is connected to the first resonant pipe 131 near one end of the first thermoacoustic conversion unit 11 through the connecting pipe 3, and the second end of the first liquid-metal MHD generator 21 is connected to the fourth resonant pipe 134 near one end of the second thermoacoustic conversion unit 12 through the connecting pipe 3, i.e. the first liquid-metal MHD generator 21 is connected between the first resonant pipe 131 and the fourth resonant pipe 134.

[0072] Correspondingly, the second liquid-metal MHD generator 22 is arranged in parallel with the first liquid-metal MHD generator 21 in the same direction, the first end of the second liquid-metal MHD generator 22 is connected to the second resonant pipe 132 near one end of the second thermoacoustic conversion unit 12 through the connecting pipe 3, and the second end of the second liquid-metal MHD generator 22 is connected to the third resonant pipe 133 near one end of the first thermoacoustic conversion unit 11 through the connecting pipe 3, i.e. the second liquid-metal MHD generator 22 is connected between the second resonant pipe 132 and the third resonant pipe 133.

[0073] In this way, since the two thermoacoustic conversion units are not synchronized, there is a phase difference of 180°, while there is only a phase difference of not more than 10° between the two ends of the thermoacoustic conversion unit, so the liquid metals inside the two liquid-metal MHD generators move approximately in opposite directions, thereby reducing the vibration of the entire power generation device during operation.

[0074] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for some technical features thereof; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A liquid metal magnetohydrodynamic power generation system driven by a two-stage circuit traveling wave thermoacoustic engine, characterized in that: include: Two-stage loop traveling wave thermoacoustic engine and liquid metal magnetohydrodynamic generator set; The two-stage loop traveling wave thermoacoustic engine comprises two thermoacoustic conversion units, which are connected end to end to form a traveling wave loop; The liquid metal magnetohydrodynamic generator set includes two liquid metal magnetohydrodynamic generators, both of which include liquid metal. The two liquid metal magnetohydrodynamic generators are arranged in the traveling wave circuit. Under the action of any one of the two thermoacoustic conversion units, the liquid metals in the two liquid metal magnetohydrodynamic generators flow in opposite directions. The thermoacoustic conversion unit includes a main room temperature heat exchanger, a regenerator, a heater, a heat buffer tube and a sub-room temperature heat exchanger, wherein the main room temperature heat exchanger, the regenerator, the heater, the heat buffer tube and the sub-room temperature heat exchanger are connected end to end in sequence; The two-stage loop traveling wave thermoacoustic engine further includes a resonance tube, wherein the main room temperature heat exchanger of one of the thermoacoustic conversion units is connected to the sub-room temperature heat exchanger of another of the thermoacoustic conversion units via the resonance tube; and the sub-room temperature heat exchanger of one of the thermoacoustic conversion units is connected to the main room temperature heat exchanger of another of the thermoacoustic conversion units via the resonance tube; The two-stage loop traveling wave thermoacoustic engine further includes a cavity, which is provided in the resonance tube and communicates with the resonance tube; The resonance tubes include a first resonance tube, a second resonance tube, a third resonance tube and a fourth resonance tube; The main room-temperature heat exchanger of one of the thermoacoustic conversion units is connected to one end of one of the cavities through the first resonance tube, and the secondary room-temperature heat exchanger of the other thermoacoustic conversion unit is connected to the other end of one of the cavities through the second resonance tube; The sub-room temperature heat exchanger of one of the thermoacoustic conversion units is connected to one end of the other cavity through the third resonance tube, and the main room temperature heat exchanger of the other thermoacoustic conversion unit is connected to the other end of the other cavity through the fourth resonance tube.

2. The liquid metal magnetohydrodynamic power generation system driven by a two-stage loop traveling wave thermoacoustic engine according to claim 1 is characterized in that: The two-stage loop traveling wave thermoacoustic engine also includes a DC suppressor, and the two DC suppressors are respectively arranged at one end of the first resonance tube close to the main room temperature heat exchanger and one end of the fourth resonance tube close to the main room temperature heat exchanger.

3. The liquid metal magnetohydrodynamic power generation system driven by a two-stage loop traveling wave thermoacoustic engine according to claim 2 is characterized in that: The two liquid metal magnetohydrodynamic generators are arranged opposite to each other or in parallel between the two thermoacoustic conversion units.

4. The liquid metal magnetohydrodynamic power generation system driven by a two-stage loop traveling wave thermoacoustic engine according to claim 3 is characterized in that: When the two liquid metal magnetohydrodynamic generators are arranged opposite to each other, the first ends of the two liquid metal magnetohydrodynamic generators are connected to the second resonance tube; the second ends of the two liquid metal magnetohydrodynamic generators are connected to the third resonance tube.

5. The liquid metal magnetohydrodynamic power generation system driven by a two-stage loop traveling wave thermoacoustic engine according to claim 3 is characterized in that: When the two liquid metal magnetohydrodynamic generators are arranged opposite to each other, the first ends of the two liquid metal magnetohydrodynamic generators are connected to the first resonance tube; the second ends of the two liquid metal magnetohydrodynamic generators are connected to the fourth resonance tube.

6. The liquid metal magnetohydrodynamic power generation system driven by a two-stage loop traveling wave thermoacoustic engine according to claim 3, characterized in that: When the two liquid metal magnetohydrodynamic generators are arranged in parallel, the first end and the second end of one of the liquid metal magnetohydrodynamic generators are connected to the first resonance tube and the fourth resonance tube respectively; the first end and the second end of the other liquid metal magnetohydrodynamic generator are connected to the second resonance tube and the third resonance tube respectively.

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