35 results about "Thermoelectric efficiency" patented technology

The inventors demonstrate herein that homogeneous Ag-doped PbTe / Ag2Te composites exhibit high thermoelectric performance (˜50% over La-doped composites) associated with an inherent temperature induced gradient in the doping concentration caused by the temperature-dependent solubility of Ag in the PbTe matrix. This method provides a new mechanism to achieve a higher thermoelectric efficiency afforded by a given material system, and is generally applicable to other thermoelectric materials.

The thermoelectric material according to the present invention is characterized in that carbon nanotubes are dispersed in thermoelectric matrix powder by mechanically grinding, mixing, and treating by heating a mixed powder formed through a chemical reaction after mixing a first solution in which carbon nanotubes are dispersed and a second solution containing metallic salts. Further, a method for fabricating the thermoelectric material includes fabricating the first solution and the second solution, mixing the first solution and the second solution with each other to form a mixed solution, forming and growing a mixed powder in which carbon nanotubes and metals are mixed by a chemical reaction of the mixed solution, mechanically grinding and mixing the mixed powder, and heating the ground-and-mixed mixed powder to form the thermoelectric material. In addition, a composite can be made from the thermoelectric material by performing a spark plasma sintering process using the thermoelectric material, and has an improved thermoelectric efficiency due to the carbon nanotubes dispersed in the thermoelectric materials.

The invention relates to the technical field of thermo-acoustic generator devices, in particular to a multistage thermo-acoustic generator set and a multistage heat generative refrigeration system provided with the same. The multistage thermo-acoustic generator set comprises a plurality of sets of thermo-acoustic engines which are sequentially connected between a compressor and a generator in series. Every two adjacent sets of thermo-acoustic engines are coupled through a harmonic oscillator assembly. The harmonic oscillator assemblies are used for enabling travelling wave sound fields to be formed in the corresponding sets of thermo-acoustic engines simultaneously. Every two adjacent two sets of thermo-acoustic engines are matched well by utilization of one harmonic oscillator assembly. The travelling wave sound fields can be simultaneously formed in the multiple sets of the thermo-acoustic engines, so that the thermoelectric efficiency of the thermo-acoustic generator set is improved. Meanwhile, the working temperatures of the multiple sets of the thermo-acoustic engines are set to be different, and accordingly gradient utilization of different-grade heat energy can be further achieved through the multistage thermo-acoustic generator set, so that the multistage heat regenerative refrigeration system provided with the multistage thermo-acoustic generator set has the higher thermoelectric conversion efficiency.

The invention provides a tower solar thermal power plant utilizing a supercritical water heat absorber and molten salt heat storage. The tower solar thermal power plant comprises a condensate pump, a deaerator, a water supply pump, the supercritical water heat absorber, a molten salt heat storage system, a steam turbine, a power generator and a condenser; the molten salt heat storage system comprises a water and molten salt heat exchanger, an expanding device, a cold salt tank, a hot salt tank, a cold salt pump, a hot salt pump and a molten salt and water heat exchanger; the condensate water is heated through the deaerator and input into the supercritical water heat absorber through the water supply pump, the solar radiation is absorbed, and the deaerated water is converted into the supercritical water to enter into the steam turbine to for work applying and power generation. The tower solar thermal power plant is combined with the work applying and power generation of the supercritical water and the molten salt heat storage and accordingly the tower solar thermal power plant can be suitable for various solar radiation conditions and the thermoelectric conversion efficiency is high; the work applying of the supercritical water is high in efficiency and free of phase change and accordingly the high thermoelectric efficiency can be guaranteed through a simple single-stage heat storage system; meanwhile the risk that the molten salt is solidified in the upper tower process is voided in comparison with a molten salt heat absorber.

The invention relates to a new solar energy thermal supercritical low-temperature air energy power generator which comprises a heat absorber, an expansion generator unit, a heat regenerator, a cooler, a booster pump, a refrigerator and pipeline accessories thereof and a detection and control device; and a nitrogen or mixed working medium is filled in a closed system. The working medium becomes high-pressure supercritical fluid through passing through the heat absorber, also becomes a working medium in the supercritical state through the work application and power generation of the expansion generator unit, is pressed into the heat regenerator by the booster pump for heat exchange through being condensed by the heat regenerator and the cooler and then is thermally absorbed by the heat absorber to form a closed cycle power generation system. The power generator also can be used for low-temperature heat source power generation in excess heat, waste heat, terrestrial heat and the like; and the working medium adopts carbon dioxide or mixed working medium. The supercritical low-temperature air energy power generator can generate cool air. With the adoption of the supercritical low-temperature air energy power generator, the working medium is condensed under the supercritical state, release a small quantity of heat and can circularly utilize the condensation heat. Therefore, the supercritical low-temperature air energy power generator has high thermoelectric efficiency, high energy conversion density, low unit power investment and low cost and uses less power during the cool air generation process. The supercritical low-temperature air energy power generator successfully breaks through the key technical difficulty of low thermal efficiency during the low-temperature solar energy thermal power generation.

The invention discloses a friction nanometer power generation system driven by a thermo-acoustic engine. The friction nanometer power generation system comprises the thermo-acoustic engine and a friction nanometer power generator unit (2) installed in a resonance tube (4) which is connected with the thermo-acoustic engine. According to the friction nanometer power generation system, external heat energy is converted to sound energy by utilizing the thermo-acoustic engine, then the sound energy is converted to electric energy by utilizing the friction nanometer power generation system to be output. The whole system has the advantages of compact structure, high reliability, high potential thermoelectric efficiency and the like. Compared with the thermo-acoustic power generation technology by adopting a linear motor, the friction nanometer power generation system has the advantages of low cost, simple structure, high integration level, many preparation material types and the like. Compared with the traditional friction nanometer power generator, driven by the thermo-acoustic engine, the friction nanometer power generation system can realize stable and continuous thermoelectric conversion.

The present invention relates to a thermoelectric device and a method for manufacturing the same, characterized in that a thermoelectric substance is formed on a mesh-type substrate made of a glass fiber or the like. According to the present invention, the thermoelectric substance is supported by the substrate, without a substrate formed by alumina or the like, such that, in addition to being lightweight, heat loss by the substrate is minimized, thereby maximizing thermoelectric efficiency.

The invention provides a novel minisize thermoelectric generator with better combustion stability, combustion efficiency and thermoelectric efficiency than the prior minisize generating system. The minisize thermoelectric generator comprises a combustor and a thermoelectric module, wherein the combustor uses dimethyl ether as fuel; the inner cavity of the combustor is divided into a first gas inlet cavity, a second gas inlet cavity and a combustion chamber by a first multihole plate and a second multihole plate which are parallel and aligned; the combustion chamber is positioned between the first multihole plate and the second multihole plate; an exhaust channel just faces the center between the first multihole plate and the second multihole plate and is communicated with the combustion chamber; the exhaust channel and the heat end of the thermoelectric module are used for heat transmission; and the cold end of the thermoelectric module is provided with a water cooler. Compared with the prior thermoelectric generators, the minisize thermoelectric generator has the advantages of small size, high heat conversion efficiency and greatly enhanced performance, and is worthy of wide popularization.

The invention relates to a transcritical low-temperature air energy generating set for new energy resource. The workflow of the transcritical low-temperature air energy generating set is as follows: after being pressurized by a booster pump, liquid working medium flows to a heat exchanger to output cold, is then turned into high-pressure supercritical fluid by a heat absorber, and expands to do work to generate electricity, part of the working medium is condensed by the heat exchanger, and then flows to the booster pump, and thereby an electricity-generating circulation system is formed; part of the working medium is throttled, expanded, cooled and depressurized to output cold, is then pressurized and cooled, and then flows to a throttle valve, and thereby a condensation circulation system is formed. The transcritical low-temperature air energy generating set also can be used for generating electricity with medium- and low-temperature heat sources such as residual heat, waste heat and terrestrial heat. The transcritical low-temperature air energy generating set condenses the working medium under the critical state, the cold in the system is sufficiently recycled, the power consumption of circulation is minimum, an outside cold source is not needed, the thermoelectric efficiency is high, the energy conversion density is high, the unit power investment is low, the cost is low, and the production of the cold air does not consume electricity. The transcritical low-temperature air energy generating set successfully breaks through the key difficult technology of low-temperature solar thermal power generation in terms of low thermal efficiency.

The invention discloses a supercritical carbon dioxide power circulating system and method for a fusion reactor. Aiming at different working medium conditions of different nuclear heat sources of a fusion reactor cladding layer, a divertor and a vacuum chamber, S-CO2 is heated by stage-by-stage heat regeneration on the high-pressure side and cooled by stage-by-stage heat regeneration on the low-pressure side through three stages, namely a low-temperature heat regenerator, a middle-temperature heat regenerator and a high-temperature heat regenerator; 20 percent of S-CO2 is selected to be cooledand then pressurized and heated so as to be used for heat regeneration of a low-temperature heater and cooling of the divertor and the vacuum chamber, so that the operation requirements of differentcooling media for different heat sources of three components in the reactor are met, a negative temperature effect during heat regeneration is avoided, the heat sources of all components in the reactor are effectively utilized, and the heat energy utilization efficiency is greatly improved; and compared with the current designs only using helium gas carrying cladding layer core heat and a Rankinecirculatory system with two-loop pressure water heat exchange to generate electricity, the thermoelectricity efficiency of the fusion reactor is improved to 41 percent from 30 percent, and the supercritical carbon dioxide power circulating system for the fusion reactor has the remarkable advantages of simple structure, low cost, high heat efficiency and the like.

The Invention relates to a process for transforming heat and work in a thermoelectric cycle, wherein charge carriers of an electronic gas are cyclically subjected to at least a first and second (7) heat source. Thereby, heat is exchanged between elements of the cycle representing adjacent sections (c-d, d-a) of a thermodynamic representation of the thermoelectric cycle. The process can be performed without thermal loss and without thermal (entropy) degradation of the second source, which provides a thermoelectric efficiency higher than that of Carnot cycles.

Provided is nano thermoelectric powder with a core-shell structure. Specifically, the nano thermoelectric powder of the core-shell structure of the present invention forms coating layer on the surface of nano powder prior to sintering of the nano powder. An advantage of some aspects of the present invention is that it provides thermoelectric elements having reduced thermal conductivity and enhanced thermoelectric efficiency without affecting electrical conductivity using the nano thermoelectric powder with the core-shell structure.

The invention relates to a device (1) for generating electric energy, comprising at least one heated heat-conducting base (2) having at least one projection (3) and thermoelectric elements (4) which are laterally attached to the at least one projection (3), a thermoelectric efficiency of every thermoelectric element (4) and a thermal capacity of the at least one projection (3) being matched to each other.

The thermoelectric material according to the present invention is characterized in that carbon nanotubes are dispersed in thermoelectric matrix powder by mechanically grinding, mixing, and treating by heating a mixed powder formed through a chemical reaction after mixing a first solution in which carbon nanotubes are dispersed and a second solution containing metallic salts. Further, a method for fabricating the thermoelectric material includes fabricating the first solution and the second solution, mixing the first solution and the second solution with each other to form a mixed solution, forming and growing a mixed powder in which carbon nanotubes and metals are mixed by a chemical reaction of the mixed solution, mechanically grinding and mixing the mixed powder, and heating the ground-and-mixed mixed powder to form the thermoelectric material. In addition, a composite can be made from the thermoelectric material by performing a spark plasma sintering process using the thermoelectric material, and has an improved thermoelectric efficiency due to the carbon nanotubes dispersed in the thermoelectric materials.

Provided is nano thermoelectric powder with a core-shell structure. Specifically, the nano thermoelectric powder of the core-shell structure of the present invention forms coating layer on the surface of nano powder prior to sintering of the nano powder. An advantage of some aspects of the present invention is that it provides thermoelectric elements having reduced thermal conductivity and enhanced thermoelectric efficiency without affecting electrical conductivity using the nano thermoelectric powder with the core-shell structure.

The invention discloses a point-line focusing combined solar thermal power generation system and method. A low-temperature heat collection section utilizes the characteristics of low temperature and high mirror field efficiency of line focusing to replace a preheater, a high-temperature section adopts the characteristics of high temperature and high thermoelectric efficiency of point focusing, the height of a point focusing heat absorber is reduced, and the mirror field efficiency is improved. The point-line focusing combined solar thermal power generation system is high in integration efficiency, small in loss and low in cost.

The inventors demonstrate herein that homogeneous Ag-doped PbTe / Ag2Te composites exhibit high thermoelectric performance (˜50% over La-doped composites) associated with an inherent temperature induced gradient in the doping concentration caused by the temperature-dependent solubility of Ag in the PbTe matrix. This method provides a new mechanism to achieve a higher thermoelectric efficiency afforded by a given material system, and is generally applicable to other thermoelectric materials.

A thermoelectric material comprising carbon nanotubes and lignin. The carbon nanotubes are present as fibres and the lignin is present in pores and / or voids in the carbon nanotube fibres. The lignin may act as a dopant to increase the thermoelectric efficiency of the carbon nanotubes, multi-walled carbon nanotubes in particular. A method of forming a thermoelectric material involving impregnating fibres of carbon nanotubes with lignin, is also provided. A thermoelectric element, a fabric and a thermoelectric device comprising the thermoelectric material are also provided. The thermoelectric material may be particularly useful for the production of wearable thermoelectric devices.

The invention provides a tower solar thermal power plant utilizing a supercritical water heat absorber and molten salt heat storage. The tower solar thermal power plant comprises a condensate pump, a deaerator, a water supply pump, the supercritical water heat absorber, a molten salt heat storage system, a steam turbine, a power generator and a condenser; the molten salt heat storage system comprises a water and molten salt heat exchanger, an expanding device, a cold salt tank, a hot salt tank, a cold salt pump, a hot salt pump and a molten salt and water heat exchanger; the condensate water is heated through the deaerator and input into the supercritical water heat absorber through the water supply pump, the solar radiation is absorbed, and the deaerated water is converted into the supercritical water to enter into the steam turbine to for work applying and power generation. The tower solar thermal power plant is combined with the work applying and power generation of the supercritical water and the molten salt heat storage and accordingly the tower solar thermal power plant can be suitable for various solar radiation conditions and the thermoelectric conversion efficiency is high; the work applying of the supercritical water is high in efficiency and free of phase change and accordingly the high thermoelectric efficiency can be guaranteed through a simple single-stage heat storage system; meanwhile the risk that the molten salt is solidified in the upper tower process is voided in comparison with a molten salt heat absorber.

The invention relates to a low-grade waste heat recovery antimonide thermoelectric module with high conversion efficiency and a preparation method thereof. The thermoelectric module comprises an insulating heat-conducting ceramic plate and an n-p thermoelectric unit which is fixed on the insulating heat-conducting ceramic plate and is connected in series by a metal diversion layer. The n-type thermoelectric element is composed of Ni / Fe / Mg3SbBi / Fe / Ni, and the p-type thermoelectric element is composed of Ni / Sb / CdSb / Sb / Ni. The thermoelectric material selected by the thermoelectric device belongs to antimonide, the composition elements of the thermoelectric material have the characteristics of high abundance and low price, and the thermoelectric material has thermoelectric performance comparable to that of a commercial Bi2Te3-based material. Compared with a traditional commercial Bi2Te3-based thermoelectric device, the thermoelectric device has the advantages of being high in conversion efficiency, wide in application temperature range, high in power-price ratio and the like, and the thermoelectric efficiency of the thermoelectric device is the highest value of the thermoelectric efficiency of a low-grade waste heat recovery temperature range at present. In addition, the thermoelectric module has relatively high thermal stability, the machinability of thermoelectric elements is high, and a necessary condition for realizing large-scale production and application is achieved.

The invention provides a waste straw energy source, raw material and fertilizer co-production technology and a biomass thermoelectric base three-phase clean cogeneration device thereof. The device ischaracterized in that the waste straw energy source, raw material and fertilizer co-production technology and a biomass thermoelectric base three-phase clean cogeneration device mechanism thereof areinnovated to form an agriculture and forestry waste biomass thermoelectric cogeneration intensive structure and a waste straw three-phase clean cogeneration intensive integrated structure, and is composed of an agriculture and forestry waste biomass storage and fine classification equipment system, an agriculture and forestry waste biomass cogeneration thermoelectric ash equipment system, a wastestraw clean material preparation and negative pressure dustproof equipment system, an initial heated or initial alkaline condensation hydrolysis and alcohol method hemicellulose preparation equipmentsystem, a reheated low-consumption compound and composite drug hydrolysis and cellulose preparation equipment system, a lignin and compound and composite substances thereof preparation and condensed water energy-saving environmental protection equipment system and the like. The technology and device have the advantage of providing a solution for rural agricultural environment control and agriculture and forestry waste biomass thermoelectric efficiency and the development of the waste straw energy, raw material and fertilizer co-production technology and the biomass thermoelectric base three-phase clean cogeneration device thereof.

The circuit board mainly comprises an interconnection base, a thermoelectric conductor, a joint layer, a top buffer layer, at least one heat conduction adulteration and a top routing layer. An interconnect base is attached around the peripheral sidewall of the thermoelectric conductor by a bonding layer, and a top buffer layer mixed with a thermally conductive admixture overlies the thermoelectric conductor and the interconnect base and is located between the top routing layer and the interconnect base / thermoelectric conductor. The top buffer layer has an elastic modulus smaller than that of the thermoelectric conductor, so that a stress buffer effect can be provided. The thermally conductive admixtures dispersed in the top buffer layer facilitate conduction of heat generated by a device assembled on the top routing layer from the top routing layer to the thermoelectric conductor. Therefore, the circuit board provided by the invention can show excellent thermoelectric efficiency and reliability.

The invention discloses a rapid energy-saving water heater, comprising a main shell and a heating element, wherein the heating element is sequentially provided with a ceramic matrix material, graphene and a heat-resistant insulating waterproof layer from inside to outside; the main shell has an interlayer structure, and is sequentially provided with a housing structure protecting layer, a middle insulating layer and an internal heat-resistant waterproof layer from outside to inside; the ceramic matrix material in the heating element can be a ceramic net or a ceramic column; the ingredient of the ceramic matrix material can be one of Al2O3, SiC and quartz; the graphene is deposited on the ceramic matrix material by a chemical vapor deposition method. The rapid energy-saving water heater has the beneficial effects that the water heater is high in heating rate, long in service life, acid-resistant, alkali-resistant, corrosion-resistant, high in thermoelectric efficiency, simple in structure and convenient to use.

The invention discloses a method for manufacturing a planar thermoelectric element, which is characterized in that: a piezoelectric material is used as a substrate, thermoelectric semiconductor material circuits are printed on the substrate, and circuit layers of N-type and P-type thermoelectric materials are printed on both sides of the substrate. A row of through holes is drilled at both ends of the substrate, and the through holes are plated with metal. The circuit layers on both sides are connected through the through holes plated with metal at both ends to form an alternating series circuit structure of N-P-N-P... to obtain a planar thermoelectric element. The advantage of the present invention is that the planar thermoelectric element circuit produced by this method has a compact structure and high energy density. It uses the piezoelectric material substrate to generate polarization in the normal direction, and can adjust the thermoelectric efficiency and cooling efficiency of the thermoelectric material circuit, especially when improving refrigeration efficiency. The introduction of the longitudinal electric field avoids the disadvantages of Joule heat generated by increasing the current. In addition, this process is compatible with flexible devices and can be used to prepare flexible thermoelectric conversion elements.

The present invention relates to thermoelectric power generating devices using thermoelectric elements and thereby generating electricity realizing direct conversion of heat to electric power due to difference in temperature. The present invention is targeted on improving thermoelectric efficiency of a thermoelectric device. According to the first variant of the present invention, technical result is achieved by that a) in thermoelectric element consisting of p-type leg and n-type leg jointed in serial electrical circuit, p-type leg is made of polycrystalline textured semiconductor Bi2Te3—Sb2Te3 alloy with high thermoelectric efficiency in the operating temperature range T>100° C. and b) in p-type leg, heat flux is directed from the hot end to the cold end parallel the crystallographic axis C. According to the second variant of the present invention, technical result is achieved by that a) in thermoelectric element consisting of p-type leg and n-type leg jointed in serial electrical circuit, p-type leg is made of polycrystalline textured semiconductor Bi2Te3—Sb2Te3 alloy and built up of two parts which are in perfect electrical and thermal contact and b) in part of p-type leg at low-temperature end of thermoelectric element, heat flux is directed from the hot end to the cold end transverse the crystallographic axis C, while in part of p-type leg at high-temperature end of thermocouple, heat flux is directed from the hot end to the cold end parallel the crystallographic axis C.

The invention discloses a water electrolysis hydrogen production system performance optimization method suitable for volatility input, and aims to solve the problem that performance optimization of a water electrolysis hydrogen production system suitable for volatility input cannot be realized, and the method comprises the following steps: S1, establishing a key equipment model according to a multi-energy conversion and energy transmission mechanism; s2, analyzing the output characteristics of the key parameters to the system according to the key equipment model; s3, optimizing the system flow based on the wide power regulation range and the output characteristics of the system; and S4, carrying out optimization matching on the key parameters of the key equipment. The method has the advantages that by analyzing the influence rule of key parameters and combining the service life of equipment, thermoelectric efficiency and safety constraints, the layered parameter optimization of a system and components under all working conditions can be carried out; load loading and solving can be carried out through the established electrolytic cell finite element model, an expected simulation result is obtained and analyzed, and therefore the optimization design of electrolytic cell grouping is achieved.

A thermoelectric generator of a vehicle converts thermal energy of exhaust gas of an engine into electric energy by using a thermoelectric phenomenon, and may include: a high-temperature part heated by exchange heat and a plurality of pairs of heat transfer plates mounted on an outer peripheral surface of an exhaust pipe at a predetermined interval; pairs of thermoelectric modules acquired by bonding a P-type semiconductor and an N-type semiconductor, interposed between the pairs of heat transfer plates to generate electricity, and electrically connected to each other; and a low-temperature part interposed between the pairs of thermoelectric modules and cooling inner surfaces of the pairs of thermoelectric modules. The plurality of thermoelectric modules generates electricity by a difference in temperature between heated outer surfaces and cooled inner surfaces. Thermoelectric efficiency is improved and a small-sized thermoelectric generator of a vehicle may be implemented.

The invention relates to an SOFC (Solid Oxide Fuel Cell) combined heat and power system capable of improving heat efficiency and optimizing water management, which is characterized in that combustion tail gas sequentially preheats air, reforming reaction, fuel, reforming water and domestic water, so that the comprehensive recycling of energy and water contained in the combustion tail gas is realized, the water and heat management of the system is optimized, and the thermoelectric efficiency of the system is effectively improved. According to the system, the assembly layout and the heat exchange process are optimized, the waste heat recovery heat exchanger and the condenser are additionally arranged, heat energy in tail gas is recovered through cooling water, and external heat supply is achieved; by additionally arranging the water storage tank, the circulating pipeline and the electromagnetic control valve, water in tail gas can be recycled. Water and heat management in the system operation process can be optimized, the heat efficiency of the system is greatly improved, the water consumption of the system is reduced, and the operation cost is reduced.