新型碳纤维电加热辐射管的开发

用高性能碳纤维作为发热体,采用独特的绕线结构形式,运用内热外涂的复合热效应设计,研制了一种高性能强辐射电加热管。该辐射管具有电热转换效率高,红外辐射能力强,管体设计柔性灵活,工作寿命超长等特点,可广泛应用于食品加工,家用电暖,工业烘烤等中低温炉型之中。     

玻璃套管双层吸热芯的热辐射特性研究

为降低多孔介质高温吸热器的辐射散热损失,设计一种玻璃套管-多孔介质双层吸热芯。采用实验测量和蒙特卡洛数值模拟方法,定量分析双层吸热芯的多光谱热辐射传输特性。结果表明,绝大多数太阳辐射外热源在双层吸热芯的内部被吸收（多孔介质入口段）。当工作温度为1000 K时,双层吸热芯的太阳光吸收比与自身红外辐射发射比之比达到约2.0,其辐射热效率较单层多孔介质吸热芯高约30%。     

碳纤维电热元件红外辐射特性研究

以碳纤维远红外管状电热元件为研究对象,研究了辐射反射罩的曲率及排布位置对辐射特性的影响,为获得均匀稳定的辐射场提供了参考。对比了几种不同类型的加热元件反射系统,结果表明碳纤维红外辐射反射系统的加热效果明显,加热质量较高。     

高温红外辐射釉料的应用研究

高温红外辐射釉料是一种非晶态结构的耐高温、热辐射率高、具有抗渗碳、耐腐蚀的新型红外辐射节能材料.测试和统计表明,辐射管涂敷高温红外辐射釉料后,温度均匀性得到很大改善、变形减小、寿命延长、热效率提高、节能显著.     

绞型和棒型碳纤维导线主要性能对比及问题分析

研究了两类碳纤维复合芯新型导线(棒型碳纤维复合芯导线、绞型碳纤维复合芯导线)的制造工艺、性能和结构情况等,对比了两种导线的优劣性能。结果表明:两类导线损伤多发生在紧线过程中卡线器临锚处以及压接过程中导线接续金具压接处附近,稳定结构的绞型碳纤维芯和现有配套耐张线夹难以达到默契的配合应用。最后针对上述两个问题提出了解决方案。     

绞合型碳纤维复合芯导线在新建线路中的应用研究

与目前普及应用的棒型碳纤维复合芯导线相比,绞合型碳纤维复合芯导线具有柔软性能良好、安全稳定性高、连接金具简单和架线施工方便的系列优点,是未来碳纤维复合芯导线的发展趋势。为研究该导线在500 kV新建架空输电线路工程中的应用前景,以两典型500 kV双回交流线路模型为例,分别从节材和节能的角度相应选取碳纤维复合芯导线,与推荐的铝包钢芯铝绞线方案进行综合技术经济比较,总结绞合型碳纤维复合芯导线经济性方面的优劣势,以指导实际工程应用。     

碳纤维复合芯导线在华东电网的应用分析

碳纤维复合芯导线是一种新型增容导线,它在机械、电气性能等方面都有突出的优势。通过对华东电网一条500kV线路的技术经济分析,论述了应用碳纤维复合芯导线增容改造线路,可以节省改造项目成本,但运行损耗比较大。在华东地区,基于不同的具体情况,可以利用碳纤维复合芯导线的性能优势,解决一些特殊环境下的线路增容问题。     

碳纤维电热元件的阻温特性研究

研究了发热芯线型、预处理工艺、黏结剂浓度和支撑芯的存在对碳纤维电热元件阻温特性的影响。结果表明：支撑芯的脱离、保护气氛下的瞬时高温除杂工序、采用多股线型的发热芯及适宜浓度黏结剂的定型处理可以使碳纤维电热元件获得较为稳定的阻温变化特性,降低电阻变化率;优化制备工艺,可以使无芯碳纤维电热元件的阻温特性与碳毡元件媲美,其电阻变化率较小。     

W型辐射管燃烧器热工特性数值研究

对W型辐射管燃烧器建立了数学模型,并采用数值模拟的方法对燃烧器内热工特性进行了研究,得出了辐射管输入功率、空燃比、炉膛温度以及空气入口温度等燃烧参数对辐射管热工特性的影响。结果表明,输入功率的增大将会导致辐射管表面温度均匀性降低、热效率降低等问题,空燃比在化学计量比附近时辐射管表面温差和热效率均达到最大值,提高炉膛温度和空气预热温度对辐射管热工特性的影响均利弊各有。文中的研究成果可以为W型辐射管燃烧器的设计和实际操作提供技术支持。     

ACCC导线的应用和金具的研制

介绍ACCC导线结构、主要品种、技术参数及应用实例,得出ACCC导线具有高强度、高容量、耐高温、耐腐蚀、线损低、低弧垂等技术特性,提出金具国产化研制的设想,供采用ACCC碳纤维复合芯铝绞线的研究、设计、施工参考。     

城市住宅及企业集中供热浅析

随着住宅商品化进程的进一步加快 ,以及供热商品化意识的普及 ,人们对集中供热提出了更高的要求 ,在利用其它手段诸如空调、电暖气等设施取暖的同时对集中供热进行开发     

红外加热技术的新发展

在回顾了红外加热技术领域两大产业，即工业加热、干燥、固化和人体理疗设备的基础上，指出第三大产业将是具有广泛建筑供暖市场的“壁挂式建筑辐射供暖器”。     

Experimental and modeling analysis of thermal characteristics in carbon fiber wires

To understand the thermal characteristics of carbon fiber heating wires, we tested the heating rules of carbon fiber heating wires with inner core tows of 12k and 24k and different lengths. We found that the surface temperature of the carbon fiber heating wires rose and fell quickly when the power supply was turned on and off by 82.9 and 18.3°C/min, respectively. After the quick rise period, the surface temperature tended to be steady with ±2°C of fluctuation; the steady temperature decreased as the length increased. With an increase in the length from 7 to 12 m, the steady temperature of the 12k and 24k wires reduced from 122°C and 166°C to 53°C and 71°C, respectively. Using the COMSOL Multiphysics software to simulate the carbon fiber heating wires, the simulated surface temperatures were in good agreement with the experimental results, with errors less than 7%. The convective and radiative heat transfer of the simulated carbon fiber electric heating wire decreased with an increase in length and the number of tows, and the convective heat transfer was much higher than the radiative heat transfer to indicate that the convective heat transfer is the main heat transfer mode in the heat dissipation of the carbon fiber electric heating wire. Results indicate that there is a rapid increase in temperature when power is on, and thereafter temperature remains constant. These are the important characteristics of carbon fiber heating wires.     

Bipolar plate design and fabrication using graphite reinforced composite laminate for proton exchange membrane fuel cells

A bipolar plate is designed to have high electric conductivity, low corrosion and good mechanical strength characteristics. The two most common materials adopted for bipolar plates are carbon and metal. The carbon bipolar plate has good electric conductivity and corrosion resistance but brittle. The metal bipolar plate has good mechanical strength, acceptable electrical conductivity but worse corrosion resistance. The main objective of this paper is to design and fabricate graphite composite laminate based PEMFC bipolar plate. A thermoset type phenolic resin is adopted as the matrix with a plain weave type woven graphite fiber cloth adopted as the composite laminate reinforcement. In the fabrication process, thermoset phenol-formaldehyde resin is first printed onto the plain-weave woven carbon fiber cloth and the waiting until air-dry as prepregs. Several layers of prepregs were then stacked into a mold and heated. The resin contained in the prepregs melted and cured into a composite laminate. The carbonization process is further conducted to increase the electric conductivity. The flow channels are carved and the bipolar plate is completely fabricated. The developed bipolar plates are assembled into a single cell PEMFC and tested. The composite bipolar plate performance with or without carbonization are also studied. The back side bipolar plate electric conductivity would also significantly affect the cell performance. Therefore, increasing the back side conductivity could increase the cell performance.     

Performance of low bandgap thermophotovoltaic cells in a small cogeneration system

In recent years there has been significant progress in fabrication of low bandgap thermophotovoltaic (TPV) devices, such as InGaAsSb, InGaAs and GaSb cells. However, only limited data are available in the literature with respect to the performance of these TPV cells in combustion-driven radiant sources. In this study, power generation using InGaAsSb TPV cells has been investigated in a gas-fired home heating furnace. The radiant power density and radiant efficiency of a gas-heated radiator were determined at different degrees of exhaust heat recuperation. Heat recuperation is shown to have a certain effect on combustion operation and radiant power output. The electric output characteristics of the InGaAsSb TPV devices were investigated under various operating conditions. An electric power density of 5.4×10³ W m⁻² was produced at a radiator temperature of 1463 K for the small cogeneration system. The cell short circuit density was observed to be greater than 1×10⁴ A m⁻² at a radiator temperature of 1203 K. Furthermore, the design aspects of combustion-driven TPV systems have been discussed. It is shown that development of a special combustion device with high conversion level of fuel chemical energy to useful radiant energy is required, to improve further the system efficiency.     

Heat transfer modelling of a plate radiator for district heating applications

The paper presents a heat transfer model of a plate radiator for district heating applications, developed by the authors. A microcomputer program based on the model was implemented for use in design and simulation of radiator space heating systems. The theoretical model is compared with a model based on experimental data. Results from using the new model to evaluate the accuracy of the German standard DIN 4703 (Q/Q_o = (LMTD/LMTD₀)^1.3) for Icelandic geothermal district heating are presented. Conclusions are drawn on the basis of the results.     

低温辐射电热炉的远红外加热元件的选择

本文着重阐述了远红外加热元件的优选方法和电炉设计步骤,并列举了实例。