一种提取次表层海水冷量的新型换热方案

提出了一种新的冷媒水与海水在海中进行换热的方案.将自来水作为冷媒水,通过输水管道送入设置于海中一定深度的换热单元,与次表层海水换热后通过地下含水层输送到用冷区域.在不同管径和流速的情况下进行的热力学计算表明,流速较小、管径较小时单管换热情况较好;在满足总供冷量一定的条件下,换热管径为0.7m、流速为0.1m/s时总输水耗功及总管长最小.与陆上换热方案相比,海中换热方案能够应用于盐度较高的海区,减少输水耗功,提高海水的冷量利用率.     

地下水在小型建筑空调中的应用研究

针对夏季空调能耗高的问题,提出了一种利用地下水作为冷媒的建筑空调方案,直接利用地下水作为冷媒,冷媒水在室内风机盘管中与室内空气进行热量交换,降低室内温度,结合房顶喷淋降低房顶表面温度,以减小热负荷;通过工程实例的计算分析可以看出:与传统空调冷水机组相比,地下水空调系统节能效果达74%,系统简单,维护方便。     

大温差空调冷冻水系统的节能分析

以单位冷量空调总能耗为目标函数,对大温差空调冷冻水系统方案进行了优化计算,得出了空调冷冻水系统最佳供回水温差为7.2℃,探讨了大温差空调水系统方案的适用场合.     

Solid-liquid phase change energy storage for driving an underwater glider

物质在物相变化过程中由环境吸收热量或冷量,也可以向环境放出热量或冷量,以实现能量储存和释放.固-液相变储能过程具有较大的承压能力.利用海洋温差能驱动的水下滑翔机工作在几百米深的海水中,承受巨大的外界海水压力,选用固-液相变材料作为感温工质-储能材料,可以保证相变储能动力系统稳定可靠地工作.利用固-液相变储能机理运行的水下机器人即水下滑翔机,不需要自带能源而吸取海洋温差能获得驱动力.本文阐述相变储能机理,回顾相变储能研究的发展.以赤道附近海域为例,以水下热滑翔机相变换热管为分析对象,说明了固-液相变储能过程在水下运载器驱动上的应用.     

高效换热管中R22传热特性的试验研究与分析

针对海水冷却的特点和要求,研究了Ｒ２２在高效换热管管内蒸发和管外冷凝的传热和压降特性,并就传热特性与相关文献报道进行了比较。实验结果表明,耐腐蚀铜合金高效换热管作为冷凝时,其传热性能比普通换热管要高出一倍左右。这些研究和分析对热泵空调换热器优化设计及海水高低温热源的应用具有重要意义。     

海水源空调用盘管换热节能效果分析

为了研究海水源空调用盘管换热器节能效果,采用现场实验的方法对盘管单位管长换热量进行测定.基于实验测试值,结合工程实例,对海水源空调系统冷却水采用盘管换热器获取方式和传统冷却塔在节能、经济和环境方面进行对比.研究结果表明,管内流速越大换热量越大,在流速为0.7 m/s时,PE32的换热管单位管长换热量为27.2 W/m.此外,夏季采用盘管与海水换热制备冷却水的海水源空调系统经济性和环境效益明显.     

海水制冷热泵系统的海水换热方案分析

对海水制冷热泵系统的原理与特点进行了简要的概述,给出了三种海水制冷热泵系统的海水换热方案,并对三种方案进行了初步技术经济分析,为海水制冷热泵系统的设计与应用提供参考。     

用于单体建筑的海水空调系统

对海水空调系统应用在单体建筑上的可行性进行了研究.首先对一个典型工程系统的设计方案进行了探讨;然后按照技术经济学中的费用年值法和追加投资动态回收年法,对传统空调系统和海水源热泵空调系统进行了方案对比,结果表明,按照优惠的收费标准,采用新系统所增加投资的动态回收期为5 a.文章还对新方案不确定因素的敏感性、环境收益和能源利用效率进行了分析.     

建筑外窗热工性能对空调能耗与节能的影响分析

利用建筑环境模拟软件DeST-c,对广州某办公建筑外窗热工性能对空调能耗的影响进行了计算,计算结果表明减小外窗遮阳系数能显著降低空调能耗,当遮阳系数从0.9减小至0.2时空调耗冷量可降低26%;而外窗传热系数对空调能耗影响较小.并通过对全年逐时空调节能率进行分析,研究了遮阳系数影响空调能耗的机理,发现遮阳系数减小引起较...     

闭式深层海水供冷系统换热特性及优化设计研究

针对低纬度岛屿地区全年温度高、湿度大,空调全年运行时间长而常规能源运输成本高,传统高能耗空调系统难以适应的问题,提出一种利用深层海水供冷的闭式空调系统。根据换热特性的差异,将换热管道分为沿程垂直换热管道和海底换热盘管两部分,通过数值模拟研究管径、流速等参数对垂直管段和海底换热盘管段传热性能的影响。研究结果表明：垂直管段管径在0.6 m以内,流速在1~2 m/s范围可保证较高的换热性能;对于海底换热盘管段,最佳管径为0.025~0.050 m,最佳流速为0.4~0.8 m/s。在此基础上建立适用于垂直管段优化设计的费用年值数学模型,计算其比摩阻、流速,形成设计用水力计算表,并给出适用于海底换热盘管段工程设计的设计线算图及其修正公式。     

余热回收吸收式制冷集中空调方案研究

为回收大型炼油装置丰富的低温余热用于生活区的夏季集中空调,本文对余热资源状况和生活区集中空调建筑物供冷负荷分别进行了综合标定和统计计算,在分析比较的基础上确定采用余热热水型溴化锂吸收式制冷冷水机组和半集中式风机盘管全水型空调系统,并利用现有双管制热水集中供暖管网和泵站输送空调冷水,可以显著地节约投资。技术经济分析表明,该方案在技术上可行,节能效果和经济效益十分显著,而且可以大大改善厂区的热污染和居民的生活条件。     

燃料电池汽车高压供氢系统辅助供冷仿真

通过数值模拟的方法,从稳态和驾驶循环2种工况对供氢系统辅助供冷方案进行评价。仿真结果表明：氢气的高膨胀比有利于空调系统能耗的下降。当环境温度为45 ℃,在中国乘用车驾驶工况下,辅助供冷方案可使空调系统能耗下降5.4%。但辅助供冷方案会给空调系统的稳定运行和座舱温度的控制带来一定的挑战。     

Performance enhancement of a subcooled cold storage air conditioning system

This article experimentally investigates the enhancement of thermal performance for an air conditioning system utilizing a cold storage unit as a subcooler. The cold storage unit is composed of an energy storage tank, liquid-side heat exchanger, suction-side heat exchanger and energy storage material (ESM), water. When the cooling load is lower than the nominal cooling capacity of the system, the cold storage unit can store extra cold energy of the system to subcool the condenser outlet refrigerant. Hence, both the cooling capacity and coefficient of performance (COP) of the system will be increased. This experiment tests the two operation modes: subcooled mode with energy storage and non-subcooled mode without energy storage. The results show that for fixed cooling loads at 3.05 kW, 3.5 kW and 3.95 kW, the COP of the subcooled mode are 16.0%, 15.6% and 14.1% higher than those of the non-subcooled mode, respectively. In the varied cooling load experiments, the COP of the subcooled cold storage air conditioning system is 15.3% higher than the conventional system.     

海水冷热资源的综合利用分析

简要介绍了海水冷热资源综合利用的思路，分析了沿海城市或地区充分利用海水资源解决供冷、供暖、供淡水问题，及同时进行海水养殖和制盐的基本方案、系统构成及其经济环境效益，探讨了海水冷热费资源和化学、生物资源的综合利用模式在我国的应用和发展前景。     

A prototype flash cooling desalination system using cooling water effluents

This paper presents a flash cooling desalination system to reduce thermal pollution and also to produce freshwater using the heat rejected by the process plant into the environment. The prototype plant was erected in an existing coal‐based thermal power plant at North Chennai, India. It consists of an air‐tight barometric sealed flash cooler, positioned at a level at least 10.13 m above the ground level, for the feed seawater to flow under the effect of gravity and to maintain a low pressure. The prototype plant was tested by using a small fraction of the available flows without using any mechanical energy such as motive steam from the power plant. A freshwater production rate of 0.49% of the feed seawater is obtained from the available thermal gradient of 8.5 °C from the condenser reject heat of the power plant, and then the waste water is discharged at near intake concentration of salinity into the sea. The temperature of hot feed seawater is also reduced by 3 °C. The results are used to provide an outline technical specification for larger capacity desalination plant to meet the growing need for freshwater. This is an environment friendly desalination process and consumes no chemicals as it operates at near ambient temperature. This can be effectively utilized for the generation of freshwater, besides protecting the marine ecosystem along the shore, and reducing the load on the cooling tower or eliminating the need for it completely. Copyright © 2012 John Wiley & Sons, Ltd.     

公共建筑空调系统节能措施探讨

介绍了中国公共建筑中央空调系统能耗现状,分析了中国公共建筑中央空调系统在设计和运行管理中存在的问题,包括空调冷热负荷、空调系统新风量、空调冷热源、水系统和风系统的维护保养等,并提出了相应节能措施。     

Review of groundwater cooling systems in London

The environmental impact of the UK building stock has increased the pressure on architects, engineers and building operators to reduce the use of air conditioning in favour of more passive cooling solutions. Good progress has been made in this direction but many passive solutions are limited to new-build projects. For existing buildings, and those for which mechanical air conditioning cannot be avoided, low energy cooling capability can be incorporated to improve significantly overall efficiency. This paper focuses on one such low energy capability – cooling using groundwater, which has gained popularity in recent years in the London area. Among the reasons for this are the excellent energy efficiency and the increasing viability of water extraction systems. The paper shows that groundwater cooling technology can be incorporated into newly-build and existing buildings to help reduce the environmental impact of the UK building stock.     

夏季大空间屋顶节能喷淋器的实验研究

针对大空间建筑模型进行喷淋效果实验,通过实验得到以下结论:由于Low-E玻璃材料在夏季具有较强的温室效应,未喷淋时,屋顶内表面平均温度为56.8℃,与环境平均温差为21.9℃,增加了空调的能耗。彩钢板屋顶具有较好的保温性能,未喷淋时,屋顶内表面平均温度为40.6℃,模型内部空间平均温度为38.9℃,该温度远低于Low-E玻璃模型温度,能耗比Low-E玻璃模型小。喷淋时,Low-E内层温度比外层温度低约5.4℃;彩钢板内外层温度在喷淋时两者相差不大,仅为0.5℃,喷淋对Low-E玻璃屋顶空调节能意义明显。