较低室外温度下保证空调冷机正常节能运行的措施

冷却水循环直接决定着压缩机能否高效、稳定运行。当过渡季节室外温度较低,但建筑物内仍需要冷负荷时,采用压差供油的冷水机组运行较为困难。通过对冷凝器的传热学分析,并根据实际经验探索空调冷机在过渡季节正常和节能运行的有效措施。根据对冷却水系统在温度较低时的理论和实验结果看,对冷却水进行旁通,不仅能够保证冷水机组安全、高效稳定运行,而且能够有效节约能源。     

冷却塔直接供冷系统应用及分析

冷却塔直接供冷系统在过渡季节及冬季有制冷需求的建筑内,在室外气候条件允许的情况下是可以实现的,其运行节能效果非常显著,本文根据负荷计算确定系统为需要全年处理冷负荷的内区建筑,选定常规运行时的系统设备,再分析负荷的变化趋势以及冷却水温度的变化趋势,通过得到不同时段的冷却水温度后,对已选设备进行校核分析计算,与室内负荷进行比较,从而确定是否由冷却塔直接供冷,实现低能耗、低费用运行。     

冬季冷却塔供冷系统在长沙卷烟厂的节能应用

本文通过对长沙卷烟厂生产车间冬季和过渡季节的供冷需求和长沙室外气象条件的分析,提出在冬季和过渡季节,采用冷却塔对产热量较大的卷烟生产车间进行供冷,可实现冷冻站节能运行的目的。本文结合长沙卷烟厂的运行实践,对冬季或过渡季节冷却塔供冷的系统设计、热工性能、全年运行时间、节能效果以及投资回收期进行了计算和分析。     

博西华家用电器有限公司供冷供热系统设计

介绍了厂房供冷供热系统设计。采用多能源联合制冷方式为舒适性空调及不同温度的工艺冷却水提供冷源,冬季采用闭式冷却塔供冷,冷水系统采用二次泵变流量系统,变频控制。制冷站根据季节自动切换制冷方式以取得最佳运行模式,达到节能目的。     

冷却塔供冷在汽车涂装车间油漆降温系统中的应用

南京某汽车制造厂涂装车间的油漆降温系统,在冬季及过渡季节采用冷却塔供冷。对切换温度、使用时限和能耗进行了分析和探讨。该降温系统使用冷却塔供冷后,减少了全年冷水机组的工作时间,降低了运行成本,取得了良好的经济效益。     

中国计量科学研究院实验基地光学热学实验楼空调系统设计

根据不同实验室功能和温度精度要求,将该工程要求相近的实验室划分为一个区域,采用空调分区域的设计方案;室内采用送回风四管制系统,以适应不同实验室的空调精度和冬季供冷或供暖需求.充分利用室外新风作为冬季及过渡季的供冷冷源;3个季节的连续测试表明,温湿度控制满足要求,空调系统运行可靠稳定.     

公共建筑开式冷却塔过渡季节供冷适宜条件分析

为评价冷却塔在过渡季节或冬季非额定工况条件下的热湿交换性能,基于冷却塔的基本热湿交换原理,以开式横流湿式冷却塔为研究对象,重点分析了室外空气湿球温度ts1、冷却塔进口水温tw1及水气比μ等因素变化对冷却塔全年运行热湿交换性能以及冷却塔冷却能力偏离额定工况的影响规律;并分析讨论了北京、南京、西安、重庆地区冷却塔过渡季节(冬季)供冷运行的适宜条件。     

利用蒸汽双效溴化锂吸收式热泵回收热电厂余热的研究

针对热电厂大量低温余热回收再利用问题,以天津市某热电厂民用建筑的空调冷热源改造工程为例,设计了一套热电厂余热回收系统。该系统采用蒸汽双效溴化锂吸收式热泵机组作为空调冷热源,冬季利用锅炉45℃脱硫塔循环水余热供热、夏季利用20℃锅炉给水作为冷却水实现供冷,过渡季节回收脱硫塔循环水余热加热锅炉给水,可实现机组全年运行。利用EnergyPlus能耗模拟软件对原有空调系统和热回收系统的运行能耗进行了模拟,结果表明该热回收系统具有良好的节能环保效益与经济收益。     

热回收型空气源热泵机组性能的实验研究

本文介绍了热回收型空气源热泵机组工作原理,提出了该系统的合理运行模式,并对热回收型热泵机组在不同运行工况下的性能进行了实验研究,研究了生活热水温度的变化对制冷系统性能的影响.夏季工况下,机组能够对冷凝热实现有效的回收利用,机组综合性能系数随着生活热水温度变化,平均达到3.39.冬季工况下可实现同时提供空调供暖和生活热水加热,但应合理没定生活热水进水温度.过渡季节换向工况,加热生活热水的性能系数为1.25.     

某舰船桅杆高发热舱室热管降温技术研究

本文采用分离式热管,对桅杆舱室局部高温进行降温控制,并作为冬季及过渡季节集桅杆专用柜机空调系统的替补设备。用FLUENT软件对舰船桅杆舱室的空气流动和热环境状况进行模拟,模拟结果表明:用分离式热管对舰船桅杆舱室部分机柜上方局部高温有良好的控制降温效。冬季及过渡季节仅启动热管空调系统就能保障舰船舱室内电子设备运行的环境温度要求。     

Measurements of indoor thermal environment and energy analysis in a large space building in typical seasons

Shanghai International Gymnastics Stadium is the selected object for site-measurement. The site-measurements have been carried out during summer, winter, and the transitional seasons. Their indoor thermal environments were controlled by continuous air-conditioning, intermittent air-conditioning and natural ventilation, respectively. The site-measurement includes outdoor environment (the weather conditions and peripheral hallway), indoor air temperature distribution (the occupant zone temperature, radial temperature near upper openings and the vertical temperature distributions, etc.), and the heat balance of air-conditioning system, etc. It is found that temperature stratification in winter with air-conditioning is most obvious. The maximum difference of vertical temperature is 15 °C in winter. The second largest one is 12 °C in summer, and less than 2 °C in the transitional season. The results of measurements indicate that it is different in the characteristics on energy saving of upper openings during the different seasons. With heat balance measurements, it is discovered that the roof load and ventilated and infiltrated load account for larger percentages in terms of cooling and heating load. In this paper, many discussions on the results of site measurements show some characteristics and regulations of indoor thermal environment in large space building.     

大型数据中心制冷系统设计

结合北京市某大型数据中心的工程实例,介绍了对该数据中心进行制冷空调系统设计的设计思路和方法。阐述当前各种制冷形式和送风方式,并分析对比各自优劣,提出目前较节能的新方式:冷通道封闭和自然冷却。根据计算所得数据对空调系统进行设计,大致分析了系统采用的节能措施,并且进行了经济性分析和PUE计算。设计的节能亮点为:采用多台高效离心式冷水机组的冷源;将冷冻水温度从12/7℃提高至13/18℃;运用冷通道封闭的下送上回式气流组织形式;冬季和过渡季节可使用的自然冷却方式。     

Solar integrated energy system for a green building

Shanghai is characteristic of subtropical monsoonal climate with the mean annual temperature of 17.6 °C, and receives annual total radiation above 4470 MJ/m² with approximately 2000 h of sunshine. A solar energy system capable of heating, cooling, natural ventilation and hot water supply has been built in Shanghai Research Institute of Building Science. The system mainly contains 150 m² solar collector arrays, two adsorption chillers, floor radiation heating pipes, finned tube heat exchangers and a hot water storage tank of 2.5 m³ in volume. It is used for heating in winter, cooling in summer, natural ventilation in spring and autumn, hot water supply in all the year for 460 m² building area. The whole system is controlled by an industrial control computer and operates automatically. Under typical weather condition of Shanghai, it is found that the average heating capacity is up to 25.04 kW in winter, the average refrigerating output reaches 15.31 kW in summer and the solar-enhanced natural ventilation air flow rate doubles in transitional seasons. The experimental investigation validated the practical effective operation of the adsorption cooling-based air-conditioning system. After 1-year operation, it is confirmed that the solar system contributes 70% total energy of the involved space for the weather conditions of Shanghai.     

Energy savings potential of a desiccant assisted hybrid air source heat pump system for residential building in hot summer and cold winter zone in China

In hot summer and cold winter zone in China, air conditioning system has four running modes yearly including cooling with dehumidification, cooling, dehumidification and heating in residential buildings. The conventional air source heat pump (ASHP) system is not designed to independently control temperature and humidity, and is not very suitable for the dehumidification mode in the view of building energy consumption. A novel ASHP system combining radiant cooling/heating for residential buildings was presented. The main feature of this hybrid ASHP system is that desiccant wheel and cooling coil accomplish dehumidification process together, and the regenerative heat needed by the desiccant wheel is supplied by the condenser dissipated heat. Based on simulation studies and performance analysis, this paper predicts the primary energy consumption of the hybrid ASHP system in comparison with the conventional ASHP system during the cooling and heating seasons. It was found that primary energy requirement can be reduced by more than 8% in cooling with dehumidification mode, by 50% in dehumidification mode, and by more than 14% in heating mode. The study results prove that the hybrid ASHP system can keep great energy saving and running cost saving yearly, especially in the dehumidification process.     

复合式风冷热泵机组的研究开发

根据长江流域及其以南地区气候特征,研究开发了复合式热泵机组,机组的冷凝器由翅片管组和光面管组串联组成,兼具风冷冷却和蒸发冷却方式特点,介绍了机组的结构和工作原理,分析了机组的技术经济性,比较了该机组相对于风冷机组的节能效果,认为复合式机组具有市场潜力,该样机经过较长时间的实际运行,冬、夏节能效果显著。     

A raw water source heat pump air-conditioning system

Raw water source is one of the promising new heat sources that researchers are looking into along with various others water-based sources such as ground, lake, river and sewage water. Generally, the water that is taken from the environment and supplied to a water treatment facility is called raw water. In this study, the heating and cooling performance of a heat pump utilizing the heat energy of raw water supplied to a water treatment facility is investigated. The two heat pumps being investigated have a heating capacity of 65.2 kW and were installed at the site for the heating and cooling of the central control room. A brazed plate heat exchanger was used for obtaining heat energy from the raw water. The raw water source provides a favorable heat source compared to the ambient air source except in spring. In the seasons of spring and autumn, the heating and cooling load are extremely low, this is the main reason for the poor performance of the raw-water heat pump system for those seasons. The average unit COP during the heating season is 3.3, and the average unit COP for the cooling season is 7.2.     

台湾办公建筑冬季蓄能混合式地源热泵空调节能潜力分析

系统整理了台湾各地的平均地温,重点研究冬季蓄能混合式地源热泵(STES-HyGCHP)系统在台湾办公类建筑中的运行策略与节能潜力。在夏季和过渡季节的部分时间用地埋管取代冷却水塔,在冬季通过冷却水塔和地埋管联合运行带走土壤积蓄的热量并储存"冷"能,可解决土壤热容失衡问题也可提高空调主机效率。经过eQuest模拟和全年逐时迭代计算,在台南应用混合式地源热泵系统,模拟案例的全年空调系统耗能最高可降低5.85%,利用尖峰和离峰电价差,可实现电费降低7.44%,在台北这两项数值分别为3.21%和4.71%,并证实该系统为具备可持续运行的能力。地下水流动的影响和经济性在文中并未涉及。     

地源热泵系统运行中土壤温度场变化特性的实例分析

对某一地源热泵系统的实测土壤温度场数据进行了初步分析,总结了冬季、夏季及过渡季工况下土壤温度场的变化特点及其影响因素。指出地源热泵系统运行过程中的地下能量堆积问题是一个长期效应,记录分析土壤温度场的长期变化趋势对于调控地源热泵系统的运行状态具有积极的指导作用,有利于保证系统的长期可靠性和节能性。     

国内规模最大再生(海)水源热泵系统运行状况分析

本文介绍了我国目前单机制热容量最大(8.3 MW)的某再生(海)水源热泵原理、系统运行方式和运行状况,对该系统冬夏季运行时一次网供回水温度、再生水温度、环境温度和制冷(热)量等进行了在线监测,并对系统的节能减排效果进行了分析。结果表明:系统各项参数运行良好,测试期间系统供热COP均在3.2以上,系统制冷COP均在4.0以上,节能减排效果显著。