集中采暖地区住宅建筑不同采暖方式的经济性比较

对集中采暖地区住宅建筑几种主要的采暖方式进行了经济性比较,在分析比较结果的基础上,提出了采暖方式的选择原则.     

太阳能采暖在行政办公楼的应用探讨

针对行政办公楼,使用综合能源价格法对太阳能地板采暖与常规热源采暖进了经济效益对比,并对太阳能采暖与生活用热水联合进行了节能、环保效益分析,得出行政办公楼的最优采暖方案.     

低温地板辐射采暖的节能分析

介绍低温热水地板辐射采暖特点,分析保温材料对保证地板采暖使用寿命和绝热层的作用。通过采暖技术的经济性分析,得出不同采暖技术的工程造价,从而得出地板辐射采暖与散热器采暖和空调系统采暖相比费用最低、热效率高,是减少建筑能耗有效方法的结论。     

低温热水地板辐射采暖的(火用)分析

本文建立了采暖系统的分析模型 ,利用所建立的模型 ,对地板辐射采暖和传统的散热器采暖两种采暖方式进行了分析。结果表明 ,当地板辐射采暖的供回水温度为 4 5℃ 35℃时 ,与传统的散热器采暖相比 ,其效率大约高 18% ,地板辐射采暖所需供水温度低 ,可以充分利用各种低温热源及工业废热等低品位能量 ,是一种具有发展潜力的节能型采暖方式     

石油企业采暖供热燃料经济分析及调整措施

本文对石油企业采暖供热的现状进行了分析，指出了存在的问题，剖析了原因。在此基础上，对采暖供热的替代燃料的经济性进行了实证分析，最后提出了调整石油企业采暖供热燃料结构的对策。     

北方采暖地区既有建筑节能改造问题研究

本文介绍了北方城镇建筑采暖能耗现状,分析了建筑采暖需要的热量、采暖系统的过量供热,以及热源和采暖系统的效率三大因素的状况和存在问题。对目前社会关注的我国建筑采暖的政策和技术的热点问题进行了专门讨论,对热计量和供热收费改革、天然气采暖、挖掘热电联产系统节能潜力、全面利用工业生产排出的低品位余热作为城市供热的主要热源等问题进行了分析研究。对2020年采暖的节能潜力进行了预测,并提出了全面推进供热体制改革的政策建议。     

基于余热利用的导热油采暖系统设计与分析

在传统采暖系统的基础上,采用高温导热油作为采暖介质,与工业高温余热相结合,形成新型采暖供热系统。通过对比高温导热油与高温热水的优缺点,设计了以高温导热油作为采暖介质的北方地区某厂房的采暖系统,分析了采用辐射板作为导热油采暖末端的可行性和经济性。利用CFD软件对厂房内高温辐射顶板采暖形式进行了数值模拟,模拟结果显示在人体活动区形成了10~20℃温度区间,满足厂房的采暖基本需求。文中提出的以导热油作为采暖介质的工业余热回收利用采暖系统设计,是一种经济节能的采暖形式,具有一定的推广价值,为采暖系统设计提供了新思路。     

低温地板幅射采暖与散热器采暖效果的对比分析

本文通过对地板、墙面和人体之间的辐射换热计算，分析了地板幅射采暖比暖气片采暖节能的原因，对比了两种采暖方式温度场水平和垂直分布的差异、空间气流分布的差异以及两种采暖方式热源热储量的差别。通过对实测数据的对比，表明地板幅射采暖在多方面优于暖气片的采暖方式。     

太阳能供热采暖工程应用推广

本文介绍了国内外太阳能供热采暖工程应用的现状与发展,给出了以太阳能热价为基础的技术经济分析,并通过对我国太阳能热利用产品的热性能质量检测分析,指出了太阳能供热采暖工程应用的发展障碍,提出了提高太阳能供热采暖市场份额的发展目标和推广策略。     

不同采暖方式的技术经济评价分析

解决好采暖问题,不但对我国节能减排目标的实现将产生重要的影响,而且对解决老百姓"温饱"问题和建设全面小康社会具有重要意义。随着各地居民对采暖提出越来越高的要求,随着能源结构调整带来的大量新型采暖方式和技术的不断涌现,应该发展什么样的采暖方式,成为当前摆在政府和用户面前的重要问题。本文就该问题开展了比较深入的研究。在对各种采暖方式进行总结归纳的基础上,从能耗、污染物排放、经济性角度提出了比较不同采暖方式的评价指标。并以北京为案例,分析了各种采暖方式的节能环保性能和经济性特点。最后,总结了在发展和选择合理采暖方式的过程中应该注意的一些问题。     

以S - CO2为底循环工质的燃气联合循环系统优化

建立以超临界CO_2为底循环工质的联合循环系统,对比分析再压缩循环系统、部分加热循环系统、预压缩循环系统的性能参数,计算表明再压缩循环系统的效率最高。以再压缩循环为基础建立再压缩+简单循环和再压缩+部分加热循环模型,功率和效率比再压缩循环都有相应提高。对再压缩+部分加热循环进行性能参数优化,得到最佳运行工况点。     

Determination of household energy using ‘fingerprints’ from energy billing data

Electric and gas utilities (in the U.S.A.) bill their customers on a regular basis, usually monthly or bimonthly. These data provide a truly valuable information resource for energy conservation programme analysts and evaluators. This paper discusses ways to analyse such billing data. The starting point is the Princeton University score-keeping model, which permits decomposition of total household energy use into its weather-and non-weather-sensitive elements; the weather-sensitive portion is assumed to be proportional to heating degree days. The score-keeping model also allows one to compute weather-adjusted energy consumption for each household based on its billing data and model parameters; this is the model's estimate of annual consumption under long-run weather conditions. The methods discussed here extend the score-keeping results to identify additional characteristics of household energy use. The methods classify households in terms of the intensity with which the particular fuel is used for space heating (primary heating fuel vs. supplemental heating fuel vs. no heating at all with the fuel). In addition, households that use the particular fuel for air conditioning are identified. In essence, the billing data and model results define household energy use ‘fingerprints’. The billing data and model results can also be used to identify and correct anomalous bills. Finally, the methods permit careful examination and analysis of changes in energy use from one year to another. They help explain why some households show anomalously large energy savings (e.g. they began using wood as a heating fuel during the second year) or negative energy savings (e.g. very high air conditioning energy use during the second year).     

采用燃气—蒸汽联合循环冷热电三联供能源系统在焦炉煤气制液化天然气工厂的应用研究

日益恶化的全球环境问题,要求中国天然气消费与生产保持高速增长,资源的特征决定了须从多种渠道解决天然气来源问题,焦炉煤气制液化天然气作为煤制天然气的一个路线,也将逐步地成为一个新兴的行业而快速成长与发展,国家已将此技术列入了近年重点示范推广的关键技术。在这个生产过程中冷热电能消耗都比较大,本文研究的是运用燃气轮机,进行燃气—蒸汽联合循环,实现"冷热电"三联供的典型分布式能源系统,使系统的循环效率从22～23%提高到40%以上。     

Experimental investigation of a comfort heating system for a passenger vehicle with an air-cooled engine

This study describes a novel approach utilizing waste heat from the exhaust gas for comfort heating of the passenger compartment of a vehicle with an air-cooled engine. In the devised system, a water stream heated by the hot exhaust gas was sent to the passenger compartment of a commercial minibus with an air-cooled engine, and the system was tested under various operating conditions. Variations of the temperatures at several locations inside the vehicle were monitored while ambient temperatures were −3, 0, 5 and 10 °C and there were various numbers of passengers on board. It is found that the system shows a reasonable heating performance while consuming no extra fuel for this purpose, and experimental data is in good agreement with numerical results based on heat loss calculations. Results show that when the ambient temperature is above 0 °C and the engine speed is above 2500 rpm, the system yielded comfortable compartment temperatures. Compared with alternative methods using extra fuel for comfort heating, the proposed system decreases vehicle operating costs and environmental pollution caused by the heating system as well as causing a lower global warming.     

Techno-economic analysis of a novel hybrid heat pump system to recover waste heat and condensate from the low-temperature boiler exhaust gas

This paper is based on the proposal of a new waste heat recovery (WHR) system, which can be utilized to heat the boiler return water, boiler supply air, and building heating air. The system is the combination of an indirect contact condensing unit (IDCCU), a mechanical compression heat pump, and two air preheaters. The system is modeled on the basis of mass and energy balance and then thermodynamically analyzed. Improved performance results were obtained in the form of an increase in the boiler's energy efficiency of about 10.47%, with 4.87% increase in exergy efficiency. The coefficient of performance (COP) of the heat pump was increased from 1.23 to 1.45 by the addition of an air heater in the conventional heat pump. The exergy destruction in each component is calculated. Sensitivity analysis was performed to check the influence of different operating parameters on the performance of the WHR system and boiler. It can be observed from the results that for a specific refrigerant temperature and a calculated amount of mass, flow rate can maximize the condensation efficiency of IDCCU by decreasing the flue gas temperature, while the use of the air heater can further reduce the flue gas temperature, and a stream of hot air can be utilized for space heating. A comparison is made with the other system on a performance basis. The results shows a clear difference in efficiencies and profit earned.     

肝海绵状血管瘤的研究进展——图例式阐述

【摘要】 肝海绵状血管瘤(cavernous hemangioma of the liver, CHL)从胚胎发生学和组织病理学上均已确认其并非肿瘤,而是源自肝脏血窦胚胎发育障碍所致的先天性肝脏血管畸形。本文旨在从CHL的血供和血流动力学、影像学表现、临床分型和介入治疗方面进行论述,并配以例证/插图,以使读者对CHL有一全面的新认识。     

太阳能、热泵辅助燃气供热系统实验研究

搭建了太阳能、热泵辅助燃气的供热系统测试平台,对太阳能辅助燃气供热系统、热泵辅助燃气供热系统以及太阳能、热泵辅助燃气供热系统的热性能进行测试,并对三种供热系统的经济环境效益进行分析.试验结果表明,试验条件下,三种供热系统的修正后一次能源利用率分别为93.3％、92.8％、103.9％,与燃气供热系统相比,节能率分别为3...     

燃气锅炉供热系统节能技术与应用

今冬以来持续低温,北京市政府及时启动燃气供热突发事件应急预案,但天然气日用气量仍然持续突破5000万m3,已经危及到北京市燃气系统安全。本文通过调查分析燃气供暖系统存在的主要问题,介绍节能技术在燃气供热系统应用步骤和成功实例。     

Thermal performance of combined solar and pellet heating systems

Various pellet heating systems are marketed in Sweden, some of them in combination with a solar heating system. Several types of pellet heating units are available and can be used for a combined system. This article compares four typical combined solar and pellet heating systems. System 1 and 2 with a pellet stove, system 3 with a store integrated pellet burner and system 4 with a pellet boiler. The often lower efficiency of pellet heaters compared to oil or gas heaters increases the final energy demand. Consequently, heat losses of the various systems have been studied. The systems have been modeled in TRNSYS and simulated with parameters identified from measurements. For almost all systems the flue gas losses are the main heat losses except for system 3 where store heat losses prevail. Relevant are also the heat losses of the burner and the boiler to the ambient. Significant leakage losses are noticed for system 3 and 4. For buildings with an open internal design system 1 is the most efficient solution. Other buildings should preferably apply system 2 or 3. The right choice of the system depends also on whether the heater is placed inside or outside of the heated area. Unlike the expectations and results from other studies, the operation of the pellet heaters with modulating combustion power is not necessarily improving the performance. A large potential for system optimisation exists for all studied systems, which when applied could alter the relative merits of the different system types.     

An engineering model for heating energy and emission assessment The case of North Karelia, Finland

This paper presents a regional engineering model for assessing space heating energies and related greenhouse gas emissions. The objective of the modeling is to improve the quality and quantity of heating energy and emission data, especially for the benefit of local decision making. The model incorporates fuel and energy statistics, building register data, demographic parameters and technical characters of heating into a single framework, allowing explorations of fuel and heat source changes, heating electricity procurement and energy conservation. The case area of the study is the province of North Karelia in Eastern Finland. A model structure, with calibration and evaluation procedures is presented, and extensive municipal estimates of heating energy and related greenhouse gas emission are produced. New indicators characterising the sustainability of heating energy use are introduced. These include municipal per capita estimates of heating energy and emissions as well as the determination of the shares of domestic and renewable energies in space heating.