用太阳辐射转化法计算室外照度值

针对中国光气候数据资料不足、太阳辐射数据丰富以及资金有限的现状,在分析多种光气候数据采集方法的基础上,选用太阳辐射转化法获得光气候数据.引入发光功效的概念作为室外照度值和太阳辐射量转化的基本关系,并分析对比了已有的发光功效模型,运用天空晴朗指数,以重庆1991-1992年的实测数据为基础进行拟合,建立了总发光功效模型和...     

铅垂面上太阳辐射计算方法探讨

在建筑物的太阳能利用中常涉及铅垂面上太阳辐射量的计算问题，其理论计算方法中，Perez模型计算较准确但是较繁杂，Hay模型较为简明实用。在工程应用中，通过计算铅垂面上日平均辐射量而计算月总辐射量，其中Hay模型较准确。     

陕北地区太阳能热水器最佳倾角确定

随着人们生活水平的提高,人们对生活用水的需求量越来越大,已占建筑总能耗的15%~20%。陕北地区太阳能资源丰富,利用太阳能供应生活热水,对节约资源、保护环境、提高住宅综合性能具有重要意义。本文根据Klein太阳辐射量的计算方法和Hay太阳辐射量计算模型,计算了府谷、榆林、延安、黄陵四县区的太阳辐射量,并推出各地在方位角为0°时太阳能集热器的最佳安装倾角,供该地区太阳能热利用和光伏发电工程参考。     

以晴空指数为主要依据的太阳辐射分区

太阳辐射数据是建筑节能分析设计中非常重要的基础数据。目前,由于我国记录太阳辐射数据的气象台站较少,不能代表典型气候条件,因此有必要利用现有实测辐射数据推测其它相近地区的辐射数据。而推测辐射数据的前提是必须对我国太阳能辐射资源进行合理分区。本文以晴空指数为主要依据,使用聚类分析的分区方法来研究我国的太阳辐射分区,得到了全国分为9个区域的太阳辐射划分结果。     

深圳市空调设计室外气象参数的确定

通过整理深圳市典型气象年的实测数据，依据空调设计规范提供的计算方法，得出深圳市的室外空调设计参数，与已知的香港和广州的室外空调设计参数比较：同时参考香港的气象资料给出深圳市月平均大气压力、日照百分率、太阳总辐射量和太阳辐射强度等参数，供深圳市建筑空调负荷和能耗计算参考。     

兰州太阳能集热器最佳倾角的计算与分析

以兰州地区水平面上的月平均太阳辐射数据为基础,计算不同倾角斜面上的月太阳辐射量,并以集热器倾斜面上接收到的太阳辐射量最多为目标,对不同时段内太阳能集热器的最佳倾角进行了优化。通过计算得到了集热器的月最佳倾角、季最佳倾角和年最佳倾角。集热器的安装倾角不但影响其斜面上全年接收到的总太阳辐射量,还影响月太阳辐射量的分布。采用季最佳倾角安装集热器最为合理,一年改变两次倾角,4—9月时倾角为5°,10—3月时倾角为49°,其斜面获得的年太阳辐射量比采用当地纬度36°时提高了4. 8%。     

建筑节能分析太阳总辐射模型研究综述

太阳辐射是建筑节能分析的重要基础气象参数,实测数据远远不能满足需求,理论计算是目前获取辐射数据的主要途径。将常用水平面太阳总辐射模型归纳为气象参数、空间插值和基于DEM三类,详述了各自的原理和计算方法。对三类模型在建筑节能分析中的适用性进行了分析,展望了建筑节能分析用太阳辐射模型的发展趋势:气象参数模型与DEM模型的融合。     

气候变化影响空调期自然通风应用潜力的研究

气候增暖不可避免地对与室外气象条件关系密切的自然通风技术具有影响。通过建立单侧通风房间模型,利用天津市市台站1960—2010年逐时气象数据,通过理论计算,从自然通风驱动力和室内热舒适2个方面研究自然通风对气候变化的适应性,以总综合压差和室内热舒适小时数2个指标分别评估了自然通风的应用潜力。总综合压差越大、室内热舒适的小时数越多,自然通风的应用潜力就越大。结果表明随着气候变暖,总综合压差及室内舒适总小时数呈下降趋势,说明天津地区自然通风的应用潜力正变得越来越小。     

全国主要城市晴天逐时太阳辐射强度与太阳能集热器最佳倾斜角度的模拟计算

依据太阳辐射相关理论和计算模型,运用VB编写程序,计算了全国主要城市全年晴天水平面和任意角度倾斜面上的太阳辐射量,日出时间、日落时间、峰值、全天累计辐射量以及太阳能集热器用于全年和仅冬季采暖所对应的最佳倾斜角度。可预测计算本地区太阳辐射量,并能为相近地区太阳辐射量计算提供参考。能满足一般太阳能工程和科学研究的需要。     

基于全景图的城市街区太阳日总辐射计算方法对比

太阳辐射是影响城市室外热环境的关键气象要素。在西安建筑科技大学校园内18个具有不同街道形态特征的地点进行了太阳辐射日总值实测,并利用百度地图平台获取了街道全景图。利用PTgui和Rayman模型软件对全景图进行分析后获取了鱼眼图像、天空开阔度(SVF,Sky view factor)和树木遮挡水平(TVF,Tree view factor)数据,在每个测点利用鱼眼图像与SVF分别采用两种不同的计算方法对该测点的太阳总辐射日总值进行了计算,并依据TVF对每个测点进行了分类。将计算结果与实测结果对比后,结合分类结果,发现在TVF较大(TVF≥0. 3)和较小(TVF 0. 3)的点分别采用不同的方法,得出的计算值与实测值更接近。综上,为了保证计算结果的准确性,在进行测试城市中不同地点的太阳辐射日总值计算时,应依据测点的环境形态特征选取不同的计算方法。     

太阳辐射直散分离模型比较研究——以北京地区为例

在建筑能耗模拟与太阳能建筑系统设计中,逐时的太阳直射和散射气象数据是最重要的基本参数。由于中国辐射观测数据的缺失,逐时直射和散射数据很难获得。很多学者对此进行了研究,提出了数十种直散分离模型。采用北京地区2009年—2011年3年太阳总辐射和散射实测数据,选取Erbs模型、Orglill模型、清华大学随机气象模型、宇田川光弘模型、张晴原模型5个代表性的直散分离模型进行计算验证,分析比较了实测数据和计算数据之间的相关系数R、均方根误差RMSE和相对误差RE,得出晴空指数Kt可以作为最主要的影响因子,Erbs模型预测散射的准确率最高,其次为张晴原模型和Orglill and Hollands模型。     

根据光气候数据确定隧道洞外景物亮度的方法

具体某地区隧道洞外景物亮度参考值的确定一直缺乏方便可靠的方法。为了解决这一问题,根据隧道照明的实际需求,以重庆地区一年的光气候实测数据为依据,首先以垂直面照度映射洞外景物亮度,分析它的各影响因素,然后建立了不同朝向垂直面转换发光功效和晴朗指数及太阳高度角的数学模型。经过与重庆地区其他年份实测数据的对比,证明该模型具有较高的精度。基于光气候数据中长期连续的水平太阳辐射及天气状况的观测,该方法可快速且相对精确地确定洞外景物亮度参考值。     

不同气候区建筑获得太阳辐射的动态分布特征

提高太阳能资源在建筑中的利用水平是减缓建筑对传统能源依赖程度的重要途径,也是推广可再生能源建筑应用的基本举措。基于全国五类气候分区代表性城市全年典型气象数据,结合计算模型研究分析了建筑屋面、东面、南面、西面、北面获得太阳辐射量的动态分布特征,确定了建筑各个方位利用太阳能资源的潜力。研究结果表明除了传统地发挥屋面利用太阳能的方法外,建筑立面接收太阳能辐射的能力也能达到良好的效果,即建筑立面利用太阳能具有较好的应用价值。     

Estimation of direct solar irradiance intercepted by a solar concentrator in different modes of tracking (case study: Algeria)

While reasonably accurate knowledge of solar radiation data at the location of interest is necessary for the design of any solar energy conversion system, the use of concentrating solar collectors implies that these systems only work with the direct solar irradiance. In the present study, by using a methodology based on simple equations, the total hourly, daily, monthly and annual direct radiations incident on four different oriented solar concentrators were calculated only from the recorded data of monthly mean daily global and diffuse horizontal solar irradiance for three different Algerian sites, in order to choose the best mode of tracking for concentrating solar thermal power systems and concentrating solar photovoltaic power systems applications. The model predictions were found to be consistent with ground measurements and prior studies of Kalogirou. It was found that the greatest energy gains were achieved by using full tracking. Furthermore, the model can be included for application to other Algerian and worldwide locations for estimating direct solar irradiance intercepted by a solar concentrator in different modes of tracking.     

温度作用设计中气象参数代表值的确定

在结构温度作用计算中需气象参数作为其边界条件,主要有日照辐射、气温日较差、风速这三个参数。根据上述环境气象参数的变化规律,在对上海地区最近30年的气象资料分析的基础上,确定了太阳辐射日最大值、夏季最大气温日较差、年最大气温日较差的概率分布接近极值I型分布,日平均风速最小值的概率分布接近正态分布。根据概率分布模型,可得到对应于不同重现期的气象参数代表值。本文所提出的方法使得结构温度作用计算中边界条件的确定建立在概率统计分析的基础上,从而使结构温度作用的计算与工程结构可靠度设计方法相协调。     

A simple model for assessing the energy performance of windows

A simple model for the annual energy balance of the window taking solar radiation and heat losses into consideration has been further developed and analysed. Hourly meteorological data for the solar irradiation and the outside temperature are used together with the optical and thermal performance of the window to evaluate the net energy heat flow through a window. The model renders a very simple way to compare different advanced windows in different geographical locations, orientations and buildings using basically only the balance temperature as building input. The energy balance and the cost efficiency for several glazing combinations are evaluated for buildings with different balance temperatures in a typical mid-Swedish climate. This model has a potential to be used for energy rating of windows.     

Solar disinfection (SODIS): simulation of solar radiation for global assessment and application for point-of-use water treatment in Haiti

Haiti and other developing countries do not have sufficient meteorological data to evaluate if they meet the solar disinfection (SODIS) threshold of 3-5 h of solar radiation above 500 W/m2, which is required for adequate microbial inactivation in drinking water. We have developed a mathematical model based on satellite-derived daily total energies to simulate monthly mean, minimum, and maximum 5-h averaged peak solar radiation intensities. This model can be used to assess if SODIS technology would be applicable anywhere in the world. Field measurements were made in Haiti during January 2001 to evaluate the model and test SODIS efficacy as a point-of-use treatment option. Using the total energy from a measured solar radiation intensity profile, the model recreated the intensity profile with 99% agreement. NASA satellite data were then used to simulate the mean, minimum, and maximum 5-h averaged peak intensities for Haiti in January, which were within 98.5%, 62.5%, and 86.0% agreement with the measured values, respectively. Most of the discrepancy was attributed to the heterogeneous nature of Haiti's terrain and the spatial resolution of the NASA data. Additional model simulations suggest that SODIS should be effective year-round in Haiti. Actual SODIS efficacy in January was tested by the inactivation of total coliform, E. coli, and H2S-producing bacteria. Exposure period proved critical. One-day exposure achieved complete bacterial inactivation 52% of the time, while a 2-day exposure period achieved complete microbial inactivation 100% of the time. A practical way of providing people with cold water every morning that has undergone a 2-day exposure would be to rotate three groups of bottles every morning, so two groups are out in the sun and one is being used for consumption.     

Quantification of model form uncertainty in the calculation of solar diffuse irradiation on inclined surfaces for building energy simulation

Traditional uncertainty quantification (UQ) in the prediction of building energy consumption has been limited to the propagation of uncertainties in model input parameters. Models by definition ignore, at least to some degree, and, in almost all cases, simplify the physical processes that govern the reality of interest, thereby introducing additional uncertainty in model predictions that cannot be captured as input parameter uncertainty. Quantification of this type of uncertainty (which we will refer to as model form uncertainty) is a necessary step towards the complete UQ of model predictions. This paper introduces a general framework for model form UQ and shows its application to the widely used sky irradiation model developed by Perez et al. [1990. “Modeling Daylight Availability and Irradiance Components from Direct and Global Irradiance.” Solar Energy 44 (5): 271–289], which computes solar diffuse irradiation on inclined surfaces. We collected a data set of one-year measurements of solar irradiation at one location in the USA. The measurements were done at surfaces with different tilt angles and orientations, for a wide spectrum of sky conditions. A statistical analysis using both this data set and published studies worldwide suggests that the Perez model performs non-uniformly across different locations and produces a certain bias in its predictions. Based on the same data, we then use a two-phase regression model to express model form uncertainty in the use of the Perez model at this particular location. Using a holdout validation test, we demonstrate that the two-phase regression model considerably reduces the model bias errors and root mean square errors for every tilted surface. Lastly, we discuss the significance of including model form uncertainty in the energy consumption predictions obtained with whole building simulation.