热管技术在锅炉装置上的运用

本文在叙述了热管基本概念和原理的基础上,论述热管技术在热管余热锅炉、多种能源锅炉、热管空气预热器和高、低压热管省煤器上的运用。随着高温热管换热器的问世,过热器亦可用热管过热器代替之。     

热管技术与化工生产中余热利用

1 热管技术简介 热管技术是一门新型传热技术,它是一种利用封闭在管内的物质反复进行物理相变(蒸发与凝结)来传递热量的一种高效能传热元件,以热管元件制成的换热器称为热管换热器.     

热管换热器的计算机辅助设计

热管是一种新型的传热元件,由热管组成的热管换热器具有传热效率高、结构紧凑、流体阻损小、有利于控制露点腐蚀等优点。这种换热器在利用热能、回收废热、节约原料、降低成本、以及一些特殊用途上(如散热)取得了显著的经济效益。随着应用市场的逐步打开,市场竞争也日趋激烈。为了适应市场需求、更为了能在时间上和技术上占领竞争的优势,针对     

家庭用节能供热系统开发

本文采用高新热管技术研制开发了一种家庭用小型节能供热装置，该装置采用并联热管组件作传热元件，以燃气(天然气，液化气)直接燃烧产生的热量作热源研制成热管锅炉。热管锅炉与热管暖气片组成家庭用节能供热系统，经实验研究表明：该系统体积小、启动快速简便、排烟温度低。节能20％～30％。     

中温太阳能热管接收器的开发与传热分析

介绍了一种新型的用于槽式太阳能热发电的中温(250～400℃)热管接收器,其结构为热管蒸发段外套单层玻璃套管,玻璃套管与热管之间抽真空,热管蒸发段外壁上涂有选择性吸收涂层,作为吸收层.该新型热管接收器主要用于直接产蒸汽系统.文中分析了该新型热管接收器的特点,并分3段模拟计算了采用该接收器的抛物面槽式太阳能集热器的集热效率和接收器的散热损失.结果表明,新开发的热管接收器结构简单、维护方便、热效率较高,适用于槽式太阳能集热器.     

国内分离式热管概况与热环研究的小结及展望

本文对我国分离式热管技术的研究进行了简要概况,针对工程中热源在上,冷源在下及冷热源相距较远时的热量传递问题,在分析了一般分离式热管及“水回路”等技术的基础上,对一种新型分离式热管－泵或风机驱动的动力型分离式热管（简称热环）的研究进行了小结和展望。     

热管技术在小化肥厂造气工段的应用

一、前言热管技术是60年代中期在美国发明的一项新型高效传热技术。热管是一种极为优良的传热元件,不仅具有重量轻、构造简单等优点,且其热传导效率为相同尺寸铜棒的数百倍。因此被称为“热的超导体”,发明初期主要应用在人造卫星热控制系统及空间核反应器,其后逐步扩大到电子元件冷却、精密机械温度控制、工业过程废热回收、空调及除湿换气能源回收、太阳能及地热利用等用途上。目前全球各先进国家均以热管技术作为高科技的一项发展目标。尽管热管技术在冶金、动力、石化等工业部门应用已取得重大经济效果。但要用于小化肥造气工段同收余热,决非易事。早在1980年人们已经考虑过采用热管回收上,下行     

径向热管换热器在天然气工业炉低温烟气中的应用

当前我国的能源形势紧张,能源利用状况令人担忧.在一些高耗能的企业,工业生产中排放的中低温烟气余热由于回收难度高、回收成本大等问题,一直得不到合理的利用,如何合理回收成为亟待解决的难题之一.简要介绍了一种新型余热利用换热设备——径向热管换热器,提出了计算热管换热器经济性评价指标的方法,并以某工厂低温烟气余热回收工程为实例,对烟气余热的回收利用进行了技术和经济效益分析.实践应用证明,径向热管换热器在工业低温烟气余热回收中有很好的实用性和可行性.     

新型分离热管式太阳能热水器

一前言本文介绍的新型分离热管,原理明了、结构简单、加工容易,生产设备及工艺均与现有热管一样;本文所述的分离热管太阳能热水器,自动运行,无需消耗额外能源,适合在寒冷地区分体安装。     

回转加热炉热管余热回收装置

一、概述 热管是一种高效传热元件。由这种元件构成的各种热管换热装置,具有传热效率高、占地面积少、阻力低等优点,近年来在热能利用和余热回收等技术领域日益受到重视。 本文介绍一种由热管余热锅炉和热管空气预热器组成的新型高温烟气余热回收装置。这套装置已研制成功,并在齐齐哈尔建     

Heat pipes application to solar energy systems

Today widespread application of energy-saving equipment based on heat pipes makes a significant contribution to the task of resources saving. Using the heat pipes as heat transfer and heat exchange design elements allows creating new effective equipment generation for solar energy systems. Heat pipes are widely used both to improve the outdated equipment, increase its efficiency, reliability and lifetime and in the creation of new high-quality and economic technology samples. Up to the present day there are the following systems and solar energy equipment where heat pipes are widely used: photovoltaic-thermal solar collectors, solar thermal collectors, concentrating photovoltaic and concentrating solar plant. The article presents an analysis of the current state and prospects of heat pipes using in solar energy systems.     

Research,development and industrial application of heat pipe technology in China

This paper introduces some typical cases of industrial applications, which include the equipment for the waste heat recovery and the industrial process equipment. Carbon steel–water heat pipe technology, applied to air preheater and waste heat boiler, has been successfully used in many fields, such as waste heat recovery, energy conservation and environmental protection. Liquid metal high-temperature heat pipe technology has been extensively employed in the process equipment, for example, high-temperature hot air generators and heat extractors. Heat pipe technology also finds its use in chemical reactors including ammonia converters. The success of applications is founded on the basis of fundamental research of heat pipe technology, which includes the theoretical and experimental researches on the vapor–liquid two-phase flow and heat transfer inside the heat pipe, the heat transfer limits of heat pipes, the heat transfer enhancement with heat pipes, and researches on the material compatibility and life tests of heat pipes. Hi-efficient heat pipe heat and mass transfer equipment is going to play a more and more important role in the various industrial fields.     

Unified Thermal Shock Resistance of Ultra-High Temperature Ceramics Under Different Thermal Environments

The thermal shock resistance (TSR) of the ultra-high temperature ceramic (UHTC) plate under convective environments is studied. The critical failure temperature difference has a danger temperature range about the thermal shock initial temperature. However, the critical failure dimensionless time decreases as the thermal shock initial temperature increases. The TSR of UHTCs is susceptible to thermal environments. The heat transfer condition shows its advantage in representing the TSR of UHTCs under different thermal environments. Universal conclusions about the TSR of UHTCs under different thermal environments are drawn using heat transfer condition. Three types of critical heat transfer condition that respectively correspond to the first, second, and third type thermal boundary conditions are introduced to characterize the TSR of UHTCs under different thermal environments similar to using various types of strength in representing the fracture-resistance abilities of the materials under different loads. The critical heat transfer condition is applied to the TSR of the UHTC plate under active cooling. The critical heat transfer condition is susceptible to the difference of the thermal shock initial temperature and the coolant temperature.     

表面活性剂对水工质超长重力热管传热性能的影响

超长重力热管是近年来被提出的用于干热岩地热能开采的一种新技术.该技术方案通过工质的沸腾?冷凝相变来进行热量传输从而在地面获得地下数千米深的热量,突破了常规热管的热力输运距离.表面活性剂能降低液体的表面张力,从而改变液体工质的沸腾特性,能在一定程度上提升常规热管的热力性能,但在超长重力热管中的作用仍有待研究.本文在自行搭...     

Enhancement of latent heat energy storage using embedded heat pipes

Latent heat thermal energy storage (LHTES) utilizing heat pipes or fins is investigated experimentally. Photographic observations, melting and solidification rates, and PCM energy storage quantities are reported. Heat pipe effectiveness is defined and used to quantify the relative performance of heat pipe-assisted and fin-assisted configurations to situations involving neither heat pipes nor fins. For the experimental conditions of this study, inclusion of heat pipes increases PCM melting rates by approximately 60%, while the fins are not as effective. During solidification, the heat pipe-assisted configuration transfers approximately twice the energy between a heat transfer fluid and the PCM, relative to both the fin-assisted LHTES and the non-heat pipe, non-fin configurations.     

A terrestrial solar energy power system

Development of an effective solar energy utilization technique is of prime importance in solving the energy crisis mankind is confronted with today. In recent years advancements have been made in high temperature measurements, high efficiency selective radiation materials, high temperature heat pipes, heat storage medium, semiconductor manufacturing techniques, space technology, etc. In this article the authors outline a solar energy utilization system (a terrestrial solar energy power system) and discuss the feasibility of a solar energy power system.     

Integration of Heat Pipe into Fuel Cell Technology

This paper describes recent applications of heat pipe technology in fuel cell systems, which include new stack designs with heat pipes to improve heat transfer as well as work on fuel cell system level design and engineering with adopting the heat pipe concept. In one design, micro-heat pipes are inserted and bonded in bipolar plates for thermal control in the fuel cell stack. In another design, flat heat pipes are integrated with a carbon bipolar plate for improving thermal control in the fuel cell stack. Finally, based on the heat pipe concept, we specifically developed a series of direct methanol fuel cell (DMFC) systems characterized as passive technology for methanol fuel delivery, water recirculation, and air and thermal management. Long-term durability and stability of the passive DMFC systems have been proved experimentally.     

Experimental investigation of wraparound loop heat pipe heat exchanger used in energy efficient air handling units

Building legislation along with environmental and comfort concerns are increasingly driving designers of building services and air conditioning equipment towards more energy efficient solutions. Heat pipe technology is emerging as a viable, efficient and environmentally-sound technology for applications in efficient air handling unit designs. In this paper, an experimental investigation on the thermal performance of an air-to-air heat exchanger, which utilises heat pipe technology, will be presented. The heat exchanger consisted of 7 loop heat pipes with finned evaporator and condenser sections. The heat exchanger was fully instrumented to test for the effect of the variation of heat load and the air velocity, through the heat exchanger, on the overall thermal resistance of the loops. The values of the effectiveness of the heat pipe heat exchanger are shown to vary with the air velocity as expected but the results also allow the prediction of effectiveness variation with the heat load and operating temperature (previously assumed to be constant). The results allow an interpretation of the overall thermal performance of each loop heat pipe as a function of the load and air velocity. The paper concludes with a theoretical analysis of the energy savings that would be expected when utilising the technology in a representative application.     

A review of the applications of heat pipe heat exchangers for heat recovery

The waste heat recovery by heat pipes is accepted as an excellent way of saving energy and preventing global warming. This paper is a literature review of the application of heat pipes heat exchangers for the heat recovery that is focused on the energy saving and the enhanced effectiveness of the conventional heat pipe (CHP), two-phase closed thermosyphon (TPCT) and oscillating heat pipe (OHP) heat exchangers. The relevant papers were allocated into three main categories, and the experimental studies were summarized. These research papers were analyzed to support future works. Finally, the parameters of effectiveness of the CHP, TPCT and OHP heat exchangers were described. This review article provides additional information for the design of heat pipe heat exchangers with optimum conditions in the heat recovery system.     

Numerical study of heat pipe application in heat recovery systems

Heat pipes are two-phase heat transfer devices with extremely high effective thermal conductivity. They can be cylindrical or planar in structure. Heat pipes can be embedded in a metal cooling plate, which is attached to the heat source, and can also be assembled with a fin stack for fluid heat transfer. Due to the high heat transport capacity, heat exchangers with heat pipes have become much smaller than traditional heat exchangers in handling high heat fluxes. With the working fluid in a heat pipe, heat can be absorbed on the evaporator region and transported to the condenser region where the vapour condenses releasing the heat to the cooling media. Heat pipe technology has found increasing applications in enhancing the thermal performance of heat exchangers in microelectronics, energy and other industrial sectors.Utilisation of a heat pipe fin stack in the drying cycle of domestic appliances for heat recovery may lead to a significant energy saving in the domestic sector. However, the design of the heat pipe heat exchanger will meet a number of challenges. This paper presents a design method by using CFD simulation of the dehumidification process with heat pipe heat exchangers. The strategies of simulating the process with heat pipes are presented. The calculated results show that the method can be further used to optimise the design of the heat pipe fin stack. The study suggests that CFD modelling is able to predict thermal performance of the dehumidification solution with heat pipe heat exchangers.