基于紫外图像相对光斑面积的绝缘子表面放电量化评估方法研究

绝缘子在运行过程中会由于表面污秽、凝露等发生表面放电,紫外成像技术作为一种绝缘子表面放电非接触式检测方法,可对绝缘子表面放电进行有效检测。常用的紫外成像光子数、光斑面积等参数会随着检测距离的变化而变化,无法实现不同检测距离时对绝缘子表面放电紫外检测的统一量化描述。基于紫外图像处理算法,研究了紫外图像相对光斑面积的计算方法,通过不同检测距离下复合绝缘子和玻璃绝缘子的紫外成像检测,验证了相对光斑面积这一参数基本不随检测距离的变化而变化,可有效实现绝缘子表面放电的量化评估。     

基于紫外图像相对光斑面积的绝缘子表面放电量化评估方法研究

绝缘子在运行过程中会由于表面污秽、凝露等发生表面放电,紫外成像技术作为一种绝缘子表面放电非接触式检测方法,可对绝缘子表面放电进行有效检测。常用的紫外成像光子数、光斑面积等参数会随着检测距离的变化而变化,无法实现不同检测距离时对绝缘子表面放电紫外检测的统一量化描述。本文基于紫外图像处理算法,研究了紫外图像相对光斑面积的计算方法,通过不同检测距离下复合绝缘子和玻璃绝缘子的紫外成像检测,验证了相对光斑面积这一参数基本不随检测距离的变化而变化,可有效实现绝缘子表面放电的量化评估。     

太阳采暖房

太阳采暖房简称太阳房,它是利用太阳的能量做为人们冬季取暖的热源,并同时加强保温的一种新型房屋。(见照片)我国北方广大地区有丰富的太阳能资源。如北京地区采暖期的日照时数为全年日照时数的三分之一,约1000小时。太阳辐照度较大:一月份太阳每天照射在一平方米南墙上的能量为3547瓦·小时。这些都为建造太阳房提供了有利条件。太阳房的平均室温比室外平均气温高     

高压设备表面放电紫外成像检测影响因素的试验研究

为研究不同因素对电晕放电紫外成像检测的影响特性,以棒-板间隙模型为研究对象,利用CoroCAM504紫外成像仪采集了不同影响因素下交流放电的紫外视频信号.试验结果表明:放电光斑面积随观测距离的增加而减小,其变化曲线近似满足幂函数关系;在相同放电强度与观测距离下,光斑面积随增益的增加而增大,其变化趋势近似满足指数函数;放...     

太阳能建筑不同朝向墙体蓄热性能差异分析

本文通过数值模拟的手段,对拉萨一栋民居建筑不同朝向围护结构的蓄热性能进行了对比研究。采用有限差分法对围护结构进行了层次划分和迭代计算,得到各朝向墙体蓄热性能状况。得到的主要结论包括：1)热惰性指标和衰减度并不能直观判断不同朝向围护结构的蓄热情况;2)不同朝向围护结构蓄热量差异明显,南墙蓄热量最多,北墙最小;3)外保温层使各个朝向墙体的蓄热量降低了50%以上;4)南墙不设保温,其他朝向设保温的情况同时利用了南向围护结构的蓄热能力和其他朝向围护结构的保温能力,室内环境舒适度高。本文的研究旨在为太阳能建筑蓄热设计提供参考,为建筑利用太阳能实现低碳和零碳目标提供技术支持。     

盐城市城镇多层居住建筑节能改造方法

为降低盐城市快速增长的采暖及制冷能耗,以盐城市城镇分布最广的6层单元式住宅建立基本模型,通过模拟得出:盐城市居住建筑采暖需求远大于制冷需求,以此确定影响采暖和制冷能耗的空间设计改造方案和围护结构热工设计改造方案。首先讨论这些改造措施对采暖能耗的影响,然后优选出采暖节能效果较好的措施,讨论其对制冷能耗及总能耗的影响。EnergyPlus87软件模拟结果表明:南向阳光间的节能效果随阳光间进深的增大而下降,最多可节能662%。北向缓冲空间的节能效果随进深的增加而升高,可节能1344%。在北墙,屋顶增加聚苯乙烯泡沫保温层的节能效果最佳,南墙次之,东、西向则收效甚微。在北墙、屋顶、南墙增加40 mm厚聚苯乙烯泡沫保温板,分别可节能939%、1033%、424%。空间组织和围护结构改造后的节能模型较基础模型节能4407%。     

不同太阳因子下复合墙壁传热过程及室内温度场的数值模拟

本文将室外空气温度与辐射温度的关系通过UDF(User Defined Functions,用户自定义功能)加载至Flunet边界条件界面,分析了夏季不同太阳因子下复合墙壁传热过程及密闭室内温度分布特性,结果表明:太阳因子从0.3增至1时,各墙体与室内温度受室外辐射的影响较大;南墙内壁面温度波动要远小于北墙内壁面;夏季...     

定西地区被动太阳房室内热环境实测研究

分析了附加阳光间被动太阳房在冬、夏季室内、外气温和相对湿度的变化情况,并对建造技术进行了阐述,提出了改造措施,以便为当地既有民居的改造和新民居的建造提供参考依据。     

基于Energyplus的附加阳光间式太阳房节能分析

本文将内蒙地区的站区公寓改造为附加阳光间式太阳房,通过动态模拟软件的计算,对模拟结果进行评价,同时对附加阳光间的经济性进行计算。结果表明附加阳光间式太阳房仅需15.93 W/m2的热量就能满足房间的采暖需求。在太阳能丰富的北方地区,对房屋进行附加阳光间节能改造是完全可行的。     

甘肃启动农村建筑节能“南墙计划”

为推动农村地区太阳能建筑一体化应用,改善农村能源结构,带动相关领域技术进步和企业发展,近日,甘肃省住房和城乡建设厅制定下发了《关于开展甘肃省农村建筑节能"南墙计划"的指导意见》,从2013年开始将在全省逐步推广实施农村建筑节能"南墙计划"。"南墙计划"是指在农村地区建筑物朝阳的南立面上加设阳光间、暖廊,配设太阳能光热、光伏等设施设     

Computer simulation of sunlight concentration due to façade shape: application to the 2013 Death Ray at Fenchurch Street,London

Reflected sunlight from the Walkie-Talkie building in 20 Fenchurch Street, London, was reported to have caused the melting of plastic components of a car parked at street level in late August of 2013. The incident was explained by the concave-shaped south façade of the building, which converges solar radiation into a hotspot. In this study, we test the sunlight concentation hypothesis with a lighting simulation. A geometry model with material properties was created, and different weather situations were modelled. The results are illustrated in irradiance maps indicating time, position and peak heat fluxes. The highest simulated flux on the day of the incident was 3320?Wm^?2 (10 to 15 fold increase compared to direct solar radiation). Additionally, the specific time and day for maximum heat fluxes between June and December were determined . For the worst scenario, which was avoided becuase the sky was partially cover with clouds that day and the hotspot did not fall on street level, the simulations showed that the peak heat flux would have reached well over 4000?Wm^?2.     

遮阳板和内缩窗对建筑外窗太阳辐射的影响研究

遮阳板和内缩窗是我国南方建筑较常采用的一种遮阳形式,为研究这两种遮阳结构对建筑外窗太阳辐射的影响,计算了建筑东、南、西、北外墙上,采用遮阳板的内缩窗的太阳辐射能量。对太阳直射辐射采用投影相加法计算遮阳板和内缩墙面对建筑外窗的遮挡。计算表明:遮阳板和内缩窗可以明显减弱东、南、西侧外墙上窗户的太阳辐射,对北侧外墙窗户的遮阳作用较小。     

高层居住区太阳能与建筑一体化技术的应用

通过对太阳能与建筑一体化技术背景和本地太阳能资源情况的分析,提出太阳能热水系统分类及系统设计选用的原则,详述了日照与集热器安装部位的选择、集热器安装方位、分户太阳能热水系统的管路布置、集热器与建筑的结合等技术及应用细节。     

The performance of a passive solar house with window sunspace systems

The performance of a single family residential solar house with three different window systems is presented. Of these three systems, two are window sunspace systems that operate as a heating component in winter and as a solar chimney for summer ventilation.The first window sunspace system is a small, local one and operates like a Trombe wall. However, contrary to a Trombe wall, the system presented here allows the penetration of daylight like any window. This window system can easily be used in small apartment buildings, where extra area for full-scale sunspace is not available.The second window sunspace system is a large central one and is designed between two tilted roofs. The heat collected by this sunspace is driven down into the living area by forced convection. The central window sunspace system collects sufficient amount of energy to heat the floor, which is shaded by the neighbouring building to its south. Such a situation is frequently encountered in low-rise high density areas. The realized solution can generally be applied to such areas.Evaluation of the expected performance of the building was carried out during the design process by means of a detailed simulation model. Comparisons between actual measurements during the first year occupancy and the simulation model are presented.     

交叉双尖窄状多重温室与太阳能热利用

文章介绍了将日光温室进一步改造为内部成交叉双尖窄状的多重温室,并将这种特殊结构的温室安装在建筑物窗户外面下端的墙壁上,就构成一种窗户型太阳能热利用装置。文中详细论述了由此产生的众多优越性。     

基于daysim软件对城市形态优化探析

本研究基于daysim光模拟软件,计算出全年太阳光在建筑表面的某点曝光量总和,根据不同的城市空间形态对某栋建筑南立面采光的影响,从定量的角度分析该建筑南立面某点全年曝光量,对城市太阳能获得以及太阳能建筑一体化(BIPV)的发展提出相应的优化策略。     

Casa Termicamente Optimizada

Traditional Portuguese building forms were adapted to create this relatively massive two‐storey house in Northern Portugal, which incorporates direct solar gain, Trombe wall and water‐wall systems. Two‐year results from both free‐floating and thermostatic control modes are here discussed; one conclusion was that existing simulation methods under‐predict the performance of massive structures.     

陕北地区太阳能建筑朝向确定

太阳能建筑朝向的选择要以冬季有较多的日照和辐射,夏季避免过多的日照和辐射为基本原则.一般认为,南向及其邻近的朝向可满足这一条件,但具体界限难以确定.本文根据陕北地区各县区的太阳高度角,推算出了府谷、榆林、延安、黄陵四县区的对等日照方位角,再根据对等日照方位角确定出陕北地区太阳能建筑的最佳朝向,供大家参考.     

村镇住宅建设与太阳能利用

通过对我国太阳能资源分布情况的分析以及太阳能应用可行性研究,提出了一种既节约能源又节省投资的太阳能绿色建筑设计方案.将建筑设计技术与太阳能利用技术相结合,建造一种利用南外墙进行集热和蓄热的被动式太阳房或利用太阳能热水循环技术的主动式太阳房,解决严寒季节供暖问题以及生活热水供应问题,对发展村镇建设,提高人居环境质量,创建"和谐社会"有着重大的现实意义.     

The predicted impact of roof aperture design on the energy performance of office buildings

An investigation has been made of potential lighting electricity reductions and associated thermal impacts of replacing electric light with sunlight admitted through rooftop glazing on a single-story, prototypical office building. Experimental scale models have been used to determine the fraction of the solar radiation entering the aperture which reaches the work plane as useful illumination. This information is used in a developmental version of the building energy analysis computer program BLAST-3.0 to predict reductions in lighting electricity and the impacts on energy consumption for heating and cooling the building. The results indicate that a large fraction of the electricity consumed for lighting a single-story office building can be displaced using modest amounts of glazing in the roof. Also, both heating and cooling energy consumption reductions are possible from a daylighting system, but they are substantially smaller than the potential lighting electricity reductions. The design implications of the results are discussed and future directions for the work are outlined.