Evaluation of cooling effects: outdoor water mist fan

Evaporative spray cooling systems can be used to provide thermal relief on hot days, even in a subtropical climate such as in Japan. An experiment combining a water mist spray with a fan was conducted to cool an outdoor space and ascertain the comfort of 141 participants on hot summer days. Each participant was surveyed for ‘thermal sensation', ‘general comfort' and ‘feeling of wettedness' and skin temperature was measured before and after entering a mist. To characterize more directly the cooling effect of this particular mist system, a dry silicone rubber skin analogue including embedded heat flux sensors was heated to near-body temperature to measure the near-surface heat flux due to natural convection, forced convection by the fan alone, and the fan and mist together. It was found that the cooling effect of the mist and fan combination is highly efficient and easily exceeds the thermal load of pedestrians, yielding nearly instant decreases in skin temperature. Such outdoor technology has potential to reduce heat stress and discomfort, particularly at large outdoor events and festivals. It could also reduce the required cooling loads within individual buildings by providing inhabitants with thermal relief outdoors.     

水雾雾滴粒径的分析与研究

介绍了水雾雾滴粒径的不同表征参数以及雾滴粒径的不同测量方法,并通过试验对水雾喷头以及细水雾喷头的雾滴粒径进行了测量,对通过雾滴直径这一参数如何区分描述水雾喷头和细水雾喷头的雾滴特性提出了相应的建议。     

高压单相细水雾灭火技术研究进展

介绍了细水雾灭火技术的特点和高压单相细水雾灭火系统的构成及主要特征，分析归纳了发展细水雾灭火技术及高压单相细水雾灭火技术需要解决的关键技术，概述了国内外的最新研究进展和应用。     

细水雾系统参数对有障碍物液体火灾灭火效果的影响

利用FDS 数值模拟软件，采取控制变量法设置4 组数值模拟，分别研究细水雾系统水滴粒径、雾化角度、喷水强度、喷头高度对火源周围存在无法燃烧或尚未开始燃烧的障碍物情况下灭火效果的影响。研究发现，当火源设置为乙醇池火时，存在障碍物条件下，细水雾系统水滴粒径设置在250~400 μm，雾化角度设为120°，喷水强度设为2.0~2.5 L/（min·m2），喷头高度距障碍物1 m 时灭火效果较为理想。     

细水雾灭火系统在热处理车间的应用

简要介绍了细水雾灭火系统的特点,并对其进行了分类,从油槽发生火灾的原因、灭火设施的选择等方面对细水雾灭火系统在热处理车间的应用进行了较详细的论述,以推广细水雾灭火系统的广泛应用。     

某车间蒸发冷却通风降温系统的设计及运行测试

介绍了蒸发冷却降温技术在某工厂空冷配电室的应用,对其系统运行情况进行了测试分析,结果表明在干燥地区采用直接蒸发冷却通风降温方式消除工业余热可以满足生产需求.     

保水性铺装材料的湿气特性及表面蒸发冷却效果实验研究

保水性铺装是一种能缓解城市热岛现象的有效方法。本文实验采用高吸水、保水性矿物质作为吸水材料,制成了新型吸水、保水材料。首先对该材料的吸水、保水及表面蒸发特性进行了测试,可知该材料具有很好的吸水及保水效果;而后,利用该矿物质和木屑作为吸水材料与速硬白水泥混合制成了2种保水性实验材料,并与纯速硬白水泥材料及普通沥青路面铺装材料进行表面蒸发冷却对比实验,结果显示,与沥青铺装材料相比,该矿物质材料具有很好的表面蒸发冷却效果。     

数据中心高压细水雾灭火系统设计分析

针对数据中心内不同安全等级机房的使用功能及防护要求,通过对高压细水雾灭火系统从系统选型、喷头设置及优化系统集成等方面进行探讨分析,提出了不同机房、设备用房及工作间的高压细水雾灭火系统设计方案,并设计了具体参数,在保证灭火有效性的基础上节约投资,提高了该系统设计的灵活性及有效性。     

含添加剂细水雾灭火模型及其应用

通过对细水雾的一维瞬间模型进行修改，建立了含添加剂细水雾灭火模型，并论述了该模型的实际应用，结合已有的实验条件对模型进行了验证。主要在于通过含添加剂细水雾灭火模型，提出了细水雾中添加剂灭火有效性的评价指标K，该模型还可对已安装的细水雾灭火系统的灭火有效性进行评价，因而具有较大的实际应用意义。     

封闭式水系统全年空调的构思与分析

提出了一种可使用水冷冷水机组同时实现夏季制冷和冬季供暖的集中空调系统冷热源方案，该机组夏季可利用水冷冷水机组制冷系数高的特点而冬季又能以热泵方式工作。初步分析表明在中南部地区其全年能耗低于空气源热泵机组。     

地铁高压细水雾系统与相关专业接口分析

根据已有的工程实例和相关国家规范规定,系统全面地对上海市地铁地下车站的高压细水雾系统的设计接口进行了总结和探讨,以期对其他城市相关地铁工程设计提供借鉴和参考。     

高压细水雾灭火系统在档案库的灭火试验研究

细水雾灭火系统已被建议用于保护对水敏感的区域,如档案库房。通过试验研究了细水雾灭火系统控制与扑灭档案库房火灾的可能性,并比较不同喷头形式的细水雾灭火系统在扑救档案库房火灾中的局限性,为细水雾灭火系统在档案库房内的推广应用提供建议。     

国内某地铁加装细水雾灭火系统方案

对行业内自动灭火系统进行对比,提出细水雾灭火系统在城市轨道交通车辆上应用的优势.通过在国内某地铁加装细水雾灭火系统的实例,介绍了细水雾灭火系统的方案、系统组成及细水雾装置的配置方案,依据地方标准的要求,通过对灭火时环境参数的分析,验证了加装的细水雾灭火系统达到了设计要求,起到了灭控火的目的.     

直线加速器间细水雾灭火系统设计与分析

针对直线加速器间作为医疗建筑中的重要设备房间,其设备贵重、设置空间的辐射防护要求特殊,为解决其灭火系统不同常规的设计要求研究了设计对策。建立了灭火系统选择安全性、适用性、经济性的原则,结合应用场所的需求对各种灭火系统进行了分析,研究了直线加速器间应用细水雾灭火系统的适用性和合理性,建议采用高压细水雾灭火系统的单联锁预作用系统。以某医疗中心的直线加速器间为例,从系统选型、应用方式和设计参数等方面,说明了其高压细水雾灭火系统的设计。就设计中关注的误喷、系统的压力和水雾粒径、设计参数的问题进行了分析,并探讨了值得注意的几个问题。     

Study on a novel thermally driven air conditioning system with desiccant dehumidification and regenerative evaporative cooling

Existing desiccant cooling systems reduce the temperature of process air either by adopting evaporative coolers or incorporating vapor compression systems. While the former is restricted by inaccurate control, the latter still consumes certain quantity of electric power. To solve this problem, a thermally driven air conditioning system, which combines the technologies of rotary desiccant dehumidification and regenerative evaporative cooling, has been proposed and investigated. In addition to dehumidification, the system is capable of producing chilled water, thereby realizing separate temperature and humidity control without increasing electrical load. To find out the characteristics of produced chilled water and evaluate the feasibility and energy saving potential of this novel system, a mathematical model has been developed. Case studies have been conducted under Air conditioning and Refrigeration Institute (ARI) summer, ARI humid and Shanghai summer conditions. It is found that the system can achieve a thermal COP higher than 1.0 and an electric COP about 8.0. The temperature of chilled water produced by the system is around 14–20 °C. This chilled water can be used with capillary tube mats for radiant cooling. It is suggested that the system can also be designed as a standalone chilled water plant. As a desiccant dehumidification-based chilled water producing technology, this would expand desiccant cooling to a boarder niche application. The effects of chilled water flow rate, air distribution ratio, inlet air conditions and regeneration temperature have been analyzed in detail. Reachable handling regions, which will be helpful to system design and optimization, have been obtained.     

循环水和冷水系统的一种节能运行方式

对常规的循环水、冷水系统运行方式进行了比较分析,提出了在过渡季节冷却塔参与到冷水系统的运行方式可以降低运行费用的方法,通过实例的运行情况研究总结得出结论,该运行方式节能效果明显。     

Experimental study of cooling effects of a passive evaporative cooling wall constructed of porous ceramics with high water soaking-up ability

As a passive cooling strategy aimed at controlling increased surface temperatures and creating cooler urban environments in summer, the authors developed a passive evaporative cooling wall (PECW) constructed of porous ceramics. These ceramics possess a capillary force to soak water, which means that their vertical surface is wet up to a level higher than 100 cm when their lower end is placed in water. The present paper describes an experiment that clarifies the cooling effects of a prototype PECW constructed of pipe-shaped ceramics. The PECW is capable of absorbing water and allows wind penetration, thus reducing its surface temperature by means of water evaporation. Passive cooling effects such as solar shading, radiation cooling, and ventilation cooling can be enhanced by incorporating PECWs into the design of outdoor or semi-outdoor spaces in parks, pedestrian areas and residential courtyards. The following findings were understood from an experimental data collected over a summer period. Wet vertical surfaces of the ceramic pipe reached a height of over 1 m at an outdoor location exposed to solar radiation. Wet surface conditions can be maintained throughout successive sunny days during summer. A slight difference in the vertical surface temperatures of the ceramic pipe was found. The air passing through the PECW was cooled, and its temperature can be reduced to a minimum value by several degrees during summer daytime. It was also found that the surface temperature of the shaded ceramic pipe can be maintained at a temperature nearly equal to the wet-bulb temperature of outdoor air.     

高压细水雾对商场货架障碍火辐射热影响的研究

采用高压细水雾灭火系统,以障碍物较多的商场、超市火灾为研究对象,分析在存在障碍物遮挡的条件下火灾中产生辐射热的变化规律。相同燃烧方式下变换细水雾工作压力测量辐射热通量变化。实验结果表明:燃烧组件单侧敞开燃烧时产生的辐射热较全敞开时的辐射热强;细水雾控火效果明显,但将火焰熄灭需一定的时间;细水雾系统压力过大时雾滴直径小,容易蒸发或被吹散,难以达到燃烧物表面;细水雾系统压力太小雾滴速度不足,难以发挥作用。     

Innovative low-energy evaporative cooling system for buildings: study of the porous evaporator wall

To face the current increase of building cooling demand and the concerns related to climate changes, an energy-efficient evaporative cooling system using porous material has been developed. This article presents the innovative cooling system and a detailed hygrothermal analysis of its main element: the porous evaporator. A mathematical model and an experimental set-up are presented, which enable to determine the suitable material properties for the evaporator and its impact on the overall cooling system performance, focusing on the optimal use of both energy and water. A good agreement is observed between numerical and experimental results, and the evaporative cooling power is estimated from 12 to 72?W/m² of evaporator wall, depending on the evaporator characteristics. A parametric analysis is conducted to select the best material for the evaporative cooling system. An intrinsic permeability of the material of 4?×?10^?17?m² is recommended for this new cooling system.     

高压细水雾灭火对古建筑木构件的水渍损失研究

高压细水雾灭火系统喷雾后会对木构件造成一定的水渍损失,为了探明木构件的水渍损失情况,对10 种木材喷雾后含水率、阴干速率和腐朽状态进行研究。通过搭建实验平台进行模拟实验,测定了不同大气湿度、环境温度下高压细水雾喷雾后实验木块含水率变化情况,分析了实验木块的含水率变化趋势、阴干速率和腐朽状态。实验结果表明,高压细水雾灭火系统喷雾后实验木块含水率测定值在35%以内,阴干2 h 后木材含水率下降至20%,阴干5 h 后木材含水率下降至河南地区平衡含水率以内,封存45 d 后实验木块肉眼观察无腐朽症状。通过对济渎庙玉皇殿消防改造工程的介绍,阐明高压细水雾灭火系统在古建筑消防改造中的技术优势,为古建筑消防系统的设计提供参考。