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一种温差电单偶热电转换效率的测试方法 总被引:1,自引:0,他引:1
提出了一种温差电单偶热电转换效率的测试方法,将测定输入温差电单偶的热流量分解为测定温差电单偶的输出电功率与测定从温差电单偶流出的热流量,并用温差电热流量计测定温差电单偶冷面流出的热流量。该测试方法避免了测量输入温差电元件的热流量,因此可以不考虑温差电元件侧面对流、辐射热损失防护问题。半导体温差电材料的塞贝克系数可以是金属的几倍,因此温差电热流量计的灵敏度高,热电转换效率的测量可以获得较高精度。给出了一些温差电单偶热电转换效率的测试结果。热面温度500℃,冷面温度50℃时,碲化铅/碲化铋级联温差电单偶的最大热电转换效率测试结果为8.45%。当冷面温度固定在50℃,作者测试了一对碲化铋温差电单偶热电转换效率随热面温度变化的规律,结果显示其热电转换效率呈近似线性增长。讨论了测试误差的来源,认为测试误差主要来源于热流量计的标定误差。 相似文献
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利用商用有限元软件ANSYS建立了带接触层的分段温差电单偶模型,不仅能考虑接触电阻,还能考虑接触热阻。该模型由n-Bi2Te3/n-PbTe,p-BiSbTe/p-Zn4Sb3组成。在电偶臂总长l=5mm时,优化温差电元件得到最大热电转换效率,并分析接触电阻和接触热阻对热电转换效率的影响,以及电臂的分界面温度。结果表明,在热端温度673K,冷端温度分别为298、323、353K时,最大转换效率为11.64%,10.70%,9.50%。当接触层厚0.1mm,接触电阻率为5×10-5Ω·m(即每电臂接触电阻为150μΩ·cm2),接触热导率为kc=6W/mK时,最大转换效率降到10.15%,9.33%,8.31%。分界面温度在材料Z-T曲线交点温度附近,大约为3%~-1%范围内。 相似文献
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碲化铋温差发电模块构型优化设计 总被引:2,自引:0,他引:2
利用温差发电技术进行发动机废热回收的研究日益受到关注。为此,以热源温度250℃、热沉温度30℃为工况,考虑半导体热电材料(碲化铋)物理参数随温度的变化,数值研究了热电元件长度和截面积、导热基底厚度这3个结构参数对温差发电模块发电性能的影响。针对1维模型精度低和灵活性差的特点,建立了3维热电耦合物理模型。数值模拟结果表明:对于峰值输出功率而言,热电元件长度存在最优值,在该研究条件下,最优值在0.075~0.125 mm范围内,与理论分析结果近似,能量转化效率则随热电元件长度的增加而减小;输出功率随热电元件截面积的增大而减小,面积比功率和能量转化效率则缓慢下降;导热基底越厚,输出功率和能量转化效率均越减小。并且建立了简易实验测试装置,通过测试商用热电器件验证了物理模型的准确性。研究结果能为温差发电模块构型设计提供参考。 相似文献
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以(GeTe)0.91(PbTe)0.09固溶体合金为研究对象,通过掺杂Sb元素来降低载流子浓度,探索Sb元素含量对(GeTe)0.91(PbTe)0.09材料热电性能的影响机制,提升材料热电性能。通过熔炼、真空热压、退火结合工艺制备了一系列(GeTe)0.91-x(PbTe)0.0 9(SbTe)x材料样品,对其热电性能进行表征和研究。结果表明:掺杂Sb元素后,成分为(GeTe)0.85-(PbTe)0.09(SbTe)0.06材料热电性能最好,其ZT值在773 K条件下可达到1.65。将(GeTe)0.91(PbTe)0.09材料和(GeTe)0.85-(PbTe)0.09(SbTe)0.06材料制成温差电单偶,测试单偶的热电转换效率,(GeTe)... 相似文献
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略述温差电技术及其应用 总被引:1,自引:0,他引:1
温差电技术就是研究温差与电之间关系的科学,或者说是研究关于热能与电能相互转换的科学。在由两种不同导体构成的闭合回路中通有直流电流时,两个交接端子中的一个温度降低(吸热端),而另一个则温度升高(放热端),在两个交接端之间产生了温差,这一效应被称之为珀尔帖效应(温差电制冷、制热效应)。温差电制冷组件一般都采用半导体材料制作而成,故又称其为半导体制冷、电子制冷组件。 相似文献
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考虑温差材料的塞贝克效应及电流的珀耳帖效应,与传热方程相结合,建立了温差发电器的一维计算模型,数值模拟了温差发电器的热电耦合工作过程。主要分析了温差材料的导热系数、电阻率和塞贝克系数的变化及其变物性计算对温差发电器工作性能的影响。计算表明,材料的导热系数、电阻率及塞贝克系数对发电器转换效率的影响规律均为非线性的,其中导热系数的影响作用最明显;当发电器的温差电元件物性参数差别较大时,其内部有不同的温度分布,采用平均值计算会有明显的误差;温差材料物性参数随温度变化后,发电器工作性能有较大的变化。 相似文献
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温差发电是一种利用热能驱动热电材料内部载流子的定向迁移,将热能转换成电能的清洁能源发电技术。目前,温差发电技术已在航空航天、军事、医学、太阳能发电等领域得到广泛应用。介绍了温差发电技术在高温汽车尾气发电上的应用,主要包括大功率汽车尾气温差发电装置的设计和制作,以及温差发电装置输出性能测试平台的搭建,并测试了汽车尾气温差发电装置的输出功率和转换效率。实验表明,在一定的温度范围内,输出功率和转换效率随热端温度的升高而线性增加,在可实现的温差和热端温度下,温差发电装置输出功率可达千瓦级别,理论转换效率接近10%。 相似文献
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在传统的掺杂卤族元素基础上掺杂一定的In元素,制备出高性能的n-PbTe基温差电材料;采用中频感应熔炼炉合金化得到均匀的基体,粉碎,然后在一定温度和压力下压制粉体得到样品锭块.测试了样品的热电性能,并且用场发射透射电镜对样品进行了微观分析,结果表明掺杂合适的Pbl2和In后,可以改善材料的热电性能,在一个较宽的温度范围内材料优值都保持一个较高的值. 相似文献
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A thermoelectric generator has been manufactured and evaluated for the purpose that the behavior of heat conduction and power generating performance can be clarified when the thermoelectric generator is powered by a high‐temperature heat transfer medium oil over 500 K. The thermoelectric generator needs a compression fitting mechanism which holds heat sinks and thermoelectric generating modules so tight that desirable heat conduction can be maintained for thousands of heat cycles. The pressure required for the compression fitting mechanism was experimentally investigated with a trial manufactured thermoelectric generator. As an experimental result the compression fitting mechanism of the modules requires 0.28 MPa compressive load, which is 80% less than the recommended value by one of the module manufacturers. Electricity obtained by the trially manufactured thermoelectric generator with bismuth telluride‐based modules increases in proportion to the square of the logarithmic mean temperature difference between the heat transfer medium oil and cooling water and attains 165 W at the logarithmic temperature difference of 180 K. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 141(1): 36–44, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10042 相似文献
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Masaaki Imamura Hironori Asada Daisuke Tashima Jiro Kitagawa 《Electrical Engineering in Japan》2019,208(3-4):10-20
A spin‐thermoelectric (STE) voltage is generated when a temperature gradient ?T is applied to an element having a thin Pt layer coated on a magnetic substance. In this study, yttrium iron garnet (YIG) ferrimagnetic films prepared by liquid phase epitaxy (LPE) were tested as magnetic insulators. In addition, polycrystalline YIG slabs were tested to compare the STE voltages of film and slab samples. In a Pt coating and YIG film bilayer structure made by an ultrathin Pt layer of 1‐4 nm thickness and an LPE film of approximately 10 µm thickness, a large STE voltage of 600 µV was observed at a probe distance of 5 mm with a temperature difference ?T of 30 K. On the other hand, the STE voltage of a Pt layer and YIG slab bilayer structure was 340 µV, which is roughly half of that of the Pt/YIG‐film element. The cause of the large voltage observed experimentally for the longitudinal spin Seebeck effect element incorporating an LPE YIG film was discussed mainly from the viewpoint of the Pt layer resistivity and the effects of YIG specimen surface conditions on crystallinity and the magnetization process. 相似文献
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Purushottam Poddar 《Integrated ferroelectrics》2017,184(1):15-22
ABSTRACTSuperlattice thermoelectric materials are important for power-generation devices that are designed to convert waste heat into electrical energy. Thermoelectric technology has only occupied niche areas, such as the radioisotope thermoelectric generators for NASA'S spacecrafts, where the energy-conversion efficiency are outweighed by the application requirements. Superlattice thermoelectric materials advances and an increasing awareness of energy and environmental conservation issues have rekindled prospects for automotive and other applications of thermoelectric materials. This article reviews thermoelectric energy-conversion technology for radioisotope space power systems and several proposed applications of thermoelectric waste-heat recovery devices in the automotive industry. 相似文献
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