基于温差发电技术的空调冷凝器余热利用系统

本文项目基于半导体温差发电技术,针对压缩式空调的外机散热进行余热回收利用,将热能转换为电能,利用蓄电池进行存储。所设计的系统将温差发电系统安装在空调外机排风口,利用排风口温度与发电系统低温端之间的温差进行发电,发电量利用导线引出到电能处理单元,对蓄电池进行充电。该项目的设计是将空调冷凝器的余热回收再利用,这为减少空调能源损耗提供了一条可行性道路,具有很高的实用性和可靠性。     

转炉半导体温差发电系统结构设计及数值模拟

设计了一种回收工业转炉余热的半导体温差发电装置。针对转炉转动的特点，研究设计了风冷式的冷端结构。采用Fluent软件对温度分布及速度分布进行了数值模拟，并对计算结果进行了分析。结果表明，采用风扇顸部冲击冷却的形式可达到良好的效果，可使温差发电元件两端温差高达70℃，满足了半导体温差发电温差基本要求，该设计也满足自带风扇负载的要求。     

温差电器件低温余热发电的实验研究

本文报道以常见低温热源做能源，通过温差电技术使之转换为电能的技术途径及样机的研制，并通过对样机性能的测试对这种发电方式的社会与经济效益的初步分析评估。     

海洋温差发电

海洋温差发电郑锡荣编译海洋是世界上最大的太阳能采集器；它每年吸收的太阳能相当于３７万亿千瓦时，约为人类目前用电量的４０００倍。每平方千米大洋表面水层含有的能量相当于３８００桶石油燃烧发出的热量。从最古的水车起，人类就一宜梦想利用以波浪、海流和潮汐表现...     

温差发电技术及其在节能领域的应用

温差发电技术是利用热电转换材料直接将热能转化为电能的发电技术,具有无运动部件、体积小、重量轻、移动方便和可靠性高等特点,是绿色环保的发电方式。随着能源与环境问题的日益突出,温差发电技术在节能领域的应用日新月异,它是合理利用太阳能、地热能、海洋温差、余热和废热等热能转换为电能的有效方式。     

海洋温差发电技术

海洋温差发电的优点是几乎不会排放二氧化碳，可以获得淡水，因而有可能成为解决全球变暖和缺水这些21世纪最大环境问题的有效手段。     

温差发电技术及其一些应用

简要地介绍了温差发电的原理,热电材料方面的研究进展,并对这一技术的应用现状作了综述,指出作为利用热电转换材料将热能转化为电能的绿色发电技术,温差发电技术正引起越来越多的关注。     

海洋温差发电

在海洋里可利用潜能较大的是“温差”。海水越深越冷，在低纬度地区，海面以下1000m处和接近海面之间的温差能达到20-25℃。     

Parametric study of asymmetric thermoelectric devices for power generation

Thermoelectric devices are considered a promising technique for recycling waste heat. In the present work, a three-dimensional numerical model is developed to study the output performance of thermoelectric devices. A comprehensive analysis is performed based on a conventional π-type thermoelectric couple. The results indicate that the maximum power of thermoelectric devices generally increases with a decrease in height and an increase in cross-sectional area; the maximum efficiency exhibits the opposite trends. The best way to reduce heat losses is by using ceramic plates with higher thermal conductivity. Moreover, the parasitic internal resistance exists in the thermoelements, and its influencing factors are studied. To minimize electric losses, an asymmetric structure is proposed for thermoelectric devices. The results exhibit that the optimal cross-sectional area ratio of the p-type and n-type legs (S_p/S_n) is mainly contingent upon the thermoelectric material parameters; the greater the differences in the parameters of p-type and n-type thermoelectric materials, the greater the gains provided by the asymmetric structure. Furthermore, the experimental data present great consistency with the numerical results. The research results may help guide the design of thermoelectric devices with relatively lower power losses.     

Experimental investigation of a novel heat pipe thermoelectric generator for waste heat recovery and electricity generation

Waste heat recovery helps reduce energy consumption, decreases carbon emissions, and enhances sustainable energy development. In China, energy-intensive industries dominate the industrial sector and have significant potential for waste heat recovery. We propose a novel waste heat recovery system assisted by a heat pipe and thermoelectric generator (TEG) namely, heat pipe TEG (HPTEG),to simultaneously recover waste heat and achieve electricity generation. Moreover, the HPTEG provides a good approach to bridging the mismatch between energy supply and demand. Based on the technical reserve on high-temperature heat pipe manufacturing and TEG device integration, a laboratory-scale HPTEG prototype was established to investigate the coupling performances of the heat pipes and TEGs. Static energy conversion and passive thermal transport were achieved with the assistance of skutterudite TEGs and potassium heat pipes. Based on the HPTEG prototype, the heat transfer and the thermoelectric conversion performances were investigated. Potassium heat pipes exhibited excellent heat transfer performance with 95% thermal efficiency. The isothermality of such a heat pipe was excellent, and the heat pipe temperature gradient was within 15°C. The TEG's thermoelectric conversion efficiency of 7.5% and HPTEG's prototype system thermoelectric conversion efficiency of 6.2% were achieved. When the TEG hot surface temperature reached 625°C, the maximum electrical output power of the TEG peaked at 183.2 W, and the open-circuit voltage reached 42.2 V. The high performances of the HPTEG prototype demonstrated the potential of the HPTEG for use in engineering applications.     

相变传热在半导体热电转换中的应用

为了解决温差发电技术中发电片热端与尾气间热损失大造成输出功率和热电转化效率不高的问题,提出在尾气与温差发电片热端加装相变传热结构,并计算了加装相变结构后发电器的输出功率和效率,同时与相同传热面积时无相变传热情况进行了对比,并模拟了蒸发段管数和冷凝段高度对发电器输出功率及效率的影响。结果表明,相变结构可提高发电器的输出功率及转化效率,且输出功率随冷凝段长度增加出现峰值,蒸发段管数越多,峰值对应的冷凝段长度越长,而发电效率则随冷凝段长度增加而减少;蒸发段管数增加,输出功率和发电效率均增大。     

Developments in semiconductor thermoelectric materials

A surge in interest in developing alternative renewable energy technologies has been observed in recent years. In particular, thermoelectrics has drawn attention because thermoelectric effects enable direct conversion between thermal and electrical energy, and provide power generation and refrigeration alternatives. During the past decade, the performance of thermoelectric materials has been considerably improved; however, many challenges continue to exist. Developing thermoelectric materials with superior performance means tailoring interconnected thermoelectric physical parameters-electrical conductivities, Seebeck coefficients, and thermal conductivities for a crystalline system. The objectives of this paper are to introduce the recent developments in semiconductor thermoelectric materials, and briefly summarize the applications of such materials.     

A novel maximum power point tracker for thermoelectric generation system

In this paper, a novel hybrid maximum power point tracking (MPPT) method is proposed and investigated. The proposed MPPT technique combines the simplicity of perturb and observe (P&O) method and the fast tracking ability of open circuit voltage (OCV) method. The advantages of the proposed MPPT approach include fast tracking speed, no additional circuit required and no temporary power loss. To validate the feasibility of the proposed MPPT technique, an 1.2 kW thermoelectric generation system for industrial waste heat recovery is also constructed, experimental results show that comparing with conventional P&O technique, the proposed method can improve the tracking speed for 42.9% and 86.2% when temperature differences are ΔT = 60 °C and ΔT = 180 °C, respectively. Moreover, the energy loss can be improved by 24.0% and 87.0% when temperature differences are ΔT = 60 °C and ΔT = 180 °C, respectively.     

新型发动机排气温差发电器结构探索

根据汽车发动机排气可利用能量的形式,提出了一种新型的置于排气通道内的热电转换系统,使热电偶与热气流直接进行对流/辐射换热,将强化热流密度和转换电流密度、提高系统的温差。在使用现有热电材料的条件下,提高温差发电器的功率密度。     

Experimental investigation on heat extraction using a two-phase closed thermosyphon for thermoelectric power generation

An experimental investigation on heat extraction using a two-phase closed thermosyphon charged with water (a filling ratio of 40%) for thermoelectric power generation was conducted to study the temperature gradients on the thermosyphon and the thermoelectric conversion characteristics. Results showed that the thermosyphon had a relatively stable working state at 100–300°C, and the maximum output power increased exponentially with temperature difference, being 20 W at a temperature difference of 210°C. The power generation efficiency increased in Hill function with increasing heating power input, the maximum value being approximately 0.01924.     

水泥厂余热利用研究

本文论述了焦作水泥厂中温烟气余热发电方案研究。讨论了设计方案、设备选型并进行了技术经济分析。本文结论对同类型余热利用工程具有参考价值。     

Numerical investigation on side heat transfer enhancement in 300 kA aluminum reduction cell

Industrial test and numerical simulation were synchronously applied to analyze the side heat transfer process and enhance heat transfer in aluminum reduction cell. The 3D slice finite element model of aluminum reduction cell was developed, with which the sidewall temperature field of the cell was computed by using software ANSYS. The main influencing factors on heat dissipation were analyzed and some effective measures were proposed to enhance sidewall heat transfer. The results show that the shell temperature of the test cell and the common cell is respectively 312°C and 318°C and the ledge thickness is 16 cm and 15 cm when side coefficient of heat transfer between the shell and the surroundings is 70 W/(m²·K). With the increase of the side coefficient of heat transfer between the shell and the surroundings, the temperature of the shell decreases but the thickness of the side ledge increases when the electrolytic temperature, the ambient temperature, the coefficient of heat transfer between molten bath and ledge, the eutectic temperature and the thermo-resistance of the side lining are constant.