净全辐射表全波灵敏度的校准

介绍了在室外用两台标准总日射表和两台黑体校准过的地球辐射表提供净全福照度、日间检定净全辐射表的全波灵敏度和谙检定其长波灵敏度的结果。数据再次证明，两者之间存在明显差异，必须加以区分并分别予以校准。使用中，当净 辐照度为正时用以灵敏度，为我时用长小波灵敏度。分析表明，短波灵敏度并无实用价值。     

净全辐射表性能的测试研究

根据ＷＭＯ对全波辐射表规定的性能指标，对国产净全辐射表进行了逐项测试，着重研究辐照度大小、环境温度、光线的不同入射角度、零点漂移、罩形变化等对仪器性能的影响。再一次验证了仪器的全波和长波灵敏度之间存在着差异，阐述了测试前对半球罩充气的必要性。结果表明，国产净全辐射表的性能并不比进口仪器差。     

PSP总日射表热偏移特征及其测量总辐射误差分析

根据2004年7月～2006年5月期间北京上甸子大气区域本底站Eppley PSP总日射表观测太阳辐射数据,分析了PSP表的热偏移特征及其影响因子,并以Eppley8-48型日射表和NIP直射表分别观测的散射和直射辐射之和作为总辐射的标准值,分析了PSP总辐射的误差特点及其影响因素.研究表明:PSP总日射表的热偏移呈现正态分布特征,平均值为-8.8±2.7W·m-2;PSP表热偏移显著受到净长波辐射、风速、相对湿度和温度的影响,其中与风速和相对湿度的相关性最为明显.与标准的太阳总辐射观测值(水平面上的散射与直射辐射之和)相比,未做热偏移订正的PSP总辐射的平均误差约为-20.0W·m-2,经过当日平均热偏移订正后,平均误差接近-11.0W·m-2.PSP表测量的总辐射绝对误差也呈准正态分布特征,但晴天与云天略有区别.PSP总辐射的相对误差与太阳天顶角的变化以及云量均有相关关系,反映了半球型辐射表的余弦效应对PSP总日射表测量精度的影响.太阳辐射的强弱变化或总辐射中散射与直射所占比率的相对变化也对PSP总日射表的测量精度有一定影响.研究表明:总日射表测量的总辐射应考虑热偏移订正,总日射表标定还应考虑云的影响.     

用Lowtran 7进行分光辐射的计算研究(Ⅱ)——UVB测量仪的校准方法及影响UVB的环境因子

太阳的紫外光辐射能量随波长变化极大，与室内紫外标准灯的光谱存在着相当大的差异，如何将室内紫外标准光源标定出的工波段紫外辐射表灵敏度校正到太阳到紫外辐射的灵敏度，是观测和标定工作中必须解决的问题。该文提出了通过太阳紫外光谱测量与模式计算相结合的方法，并利用Lowtran7模式软件所能提供的计算参数，分别计算了3个紫外波段（UV－A，UV－B和UV－C）的辐照度，研究了不同太阳高度角，不同气溶胶，不同海拔高度以及大气中不同水汽和气溶胶含量对3个紫外波辐照度的影响；并以Eppley实验室制造的TUVR宽带紫外辐射表测量的紫外辐照度为例，证明了此类辐射表的测量值，并非就是紫外辐射的总量，而是其中的一部分，其所占比例随大气条件变化而改变。此外通过，证实了在紫外辐射中以散射辐射为主的情况。     

TBQ-1型总日射表的研制

本文报道了TBQ-1型总日射表的工作原理、制作工艺及主要技术性能,讨论了感应元件的灵敏度、时间响应,温度系数、内阻等与感应元件的结构和材料的关系,并对感应元件的理论估算和实测结果进行了比较。     

关于净全辐射表的长波灵敏度检定方法

讨论了区分净全辐射表长波和短波灵敏度的必要性，介绍了改进后的检定净全辐射表长波灵敏度的辐射黑体标准装置，着重研究以下三个问题，（１）在得不到密光阑圆形孔径对正文形感应形状因子解析解的情况下，所采用近似法及其误差；（２）讨论了采用动态法进行校准的必要性及静态法的弊端；（３）分析了在每次光辐射电势测量之前进行背景电势测量的必要性，因为令依据首尾两次的背景电势测量值去内插中间值的做法是不适宜的。     

地球辐射表的研制（Ⅱ）：性能比较测试研究

为研究国产TBL型地球辐射表的各项性能,通过与Eppley PIRF型地球辐射表的对比测试,发现国产仪器除灵敏度略低于Eppley PIRF外,其它性能并不逊色,而且还发现了地球辐射表的一些特性。它们在以前文献中未见报道过：如由于仪器体内存在温度梯而引起的仪器体温测不准性和Eppley PIRF性能方面的某些不足,以及在选用一台地球辐射表作为相对标准时,应注意的问题等。     

地球辐射表的研制(Ⅱ)∶性能比较测试研究

为研究国产TBL型地球辐射表的各项性能,通过与EppleyPIR型地球辐射表的对比测试,发现国产仪器除灵敏度略低于EppleyPIR外,其它性能并不逊色,而且还发现了地球辐射表的一些特性。它们在以前文献中未见报道过：如由于仪器体内存在温度梯度而引起的仪器体温测不准性和EppleyPIR性能方面的某些不足,以及在选用一台地球辐射表作为相对标准时,应注意的问题等     

北京地区太阳紫外辐射的基本特征

1990年1月至1991年3月在中国科学院大气物理研究所香河观测站(北京东南70公里处)利用国产TBQ-4型分光辐射表及配套的智能辐射记录仪，对近地面太阳紫外辐射进行了观测，得到此间北京地区近地面太阳紫外辐射及其占太阳总辐射比例的变化特征，并分析了差异的原因。给出了1990年1月至1091年3月太阳紫外辐射的极值及对应的紫外辐射占总辐射的比例，后者同太阳总辐射存在反相关。     

乘用车柴油机噪声源识别方法的试验研究

以乘用车柴油机为研究对象，通过振动速度测量技术和声强测量技术相结合的方法对该发动机进行了表面辐射噪声源识别的研究。首先在半消声室内测量了发动机的声功率，然后测量了发动机各主要噪声辐射部件振动速度并分析了各部件的振动特性，并通过其表面振动速度计算了它们各自的声功率以及对总噪声的贡献，对不适于振动测量的旋转部件采用声强法测量了其声功率，最终得到了各主要噪声源的大小排列，并且分析了这些部件的噪声辐射特性。     

Measurement and analysis of the step response of pyranometers requiring second-order correction

We have measured the time response of Kipp and Zonen CM-5 pyranometers to a step function of radiation and observed that the pyranometer output varied significantly from a single exponential function of time. Using a multi-exponential function to fit the experimental data, we extracted the two dominant exponential components of the signal to obtain the analytic function describing the pyranometer response. A thermal model of the pyranometer has been developed, whose response displays the observed time behaviour. The model was applied to correct the time response error of the pyranometers subject to a step function of incident radiation, and compared with a single exponential correction scheme.     

Field measurement of albedo for limited extent test surfaces

A new method is introduced for field measurement of surface albedo. This method consists of the use of a cylindrical shade ring made of opaque fabric with a known (low) albedo placed over a test surface. The albedo measurement is accomplished using two small pyranometers situated so that the downward-facing pyranometer receives radiation only from the test surface and the shade ring. The upward-facing pyranometer simultaneously records the incoming solar radiation. The radiation received by the downward-facing pyramometer is a combination of reflected radiation from shaded and unshaded portions of these two surfaces, requiring detailed accounting of the resulting view factor geometries. The method presented here improves upon past approaches by allowing for smaller sample sizes, minimizing errors associated with reflective properties of the surroundings, and allowing for accurate measurements even under partially cloudy skies. In addition to these methodological improvements we introduce an approach for estimating the uncertainty in the resulting albedo measurements. Results from field measurements are presented to validate the measurement protocol, and to compare its accuracy with the accuracy of a published standard.     

A multisensor pyranometer for determination of the direct component and angular distribution of solar radiation

This paper describes a technique for determining the direct component and the angular distribution of the diffuse component of solar radiation. The information is obtained by measurement of the total radiation on slopes of different orientations. This has been done using a new multidirectional pyranometer, called a multipyranometer, specially developed for this purpose. The instrument incorporates 25 radiation sensors mounted on a metal hemisphere. Each sensor consists of a blackened copper plate with a semiconductor temperature transducer. Sensors are enclosed in an evacuated glass envelope and each of them is connected to its own digital integrator. Computer programs have been developed for data quality control, monitoring and computations. Some of the results from laboratory tests and solar radiation measurement obtained over a period of two years are given. Comparisons are made between observations obtained with the multipyranometer and those obtained with conventional pyranometers. Experimental observations are also compared with some radiation models.     

A microprocessor-based rotating shadowband radiometer

High-quality solar radiation measurements are both expensive and labor intensive. An installation with detectors that are rated first class by the World Meteorological Organization and a modest data acquisition system costs about U.S. $8000 and requires frequent visits to check alignment and clean components. Motivated by these considerations and the development in our laboratory of a microprocessor-based data acquisition system, we have built and initially tested a microprocessor-controlled rotating shadowband photometer. A total horizontal solar radiation measurement is made once each minute. A corrected diffuse horizontal component is calculated from three measurements and direct normal solar radiation is calculated from these two quantities. The device can be initialized and interrogated for its accumulated data via a modem. The device is designed to require little or no maintenance; it should never need realignment, but will require occasional cleaning. Several channels of the logger are available for auxiliary measurements for the marginal costs of those sensors. These devices can be made in quantities of 50–100 at a cost of U.S. $1500 for parts and assembly. The pyranometer uses a silicon photodiode detector. For applications with tailored wavelength responses within 400–700 nm, such as photometric measurements, the device can be considered ready for use. Until corrections are derived for temperature, cosine, and spectral effects, the instrument's accuracy in a broadband solar resource measurement is low.     

Development of a simple low-cost solar simulator for indoor collector testing

Indoor test methods for solar collectors are widely accepted and recommended by ASHRAE. The development of a solar simulator for indoor testing and the certification procedure for photo-thermal solar devices is discussed in this paper. The system consists of 14 quartz halogen lamps and provides a testing area of about 1 × 1 m. The irradiance can be varied from 400 to 1500 W/m². This is achieved by varying the input power supplied to individual lamps. The radiation output characteristics of a single lamp have been studied. The distribution of intensity over the covered area of 1·20 × 1·20 m has been recorded using a precision Eppley pyranometer.A variety of collectors—evacuated tubular collectors and flat-plate collectors of both liquid and air heating types—has been tested under sufficiently stable insolation conditions. Results for a conventional solar air heater are presented together with suggestions for further improvements.     

基于光伏组件的太阳能资源观测

鉴于太阳能资源的测量和评价是太阳能开发利用的重要基础,按照光伏电池两种主要安装方式(倾斜固定和太阳跟踪),利用单晶、多晶和非晶三种典型的光伏组件设计进行了太阳能光伏资源观测试验,获得了各季节典型晴天条件下各类型光伏组件辐照度的日变化特征和倾斜面光伏组件一年中月均每日可发电量的极大值、极小值及其月份。通过对比各类型光伏组件在太阳跟踪器上和纬度倾斜面上光伏辐照度变化,得出跟踪光伏组件日均光伏曝辐量与倾斜光伏组件日均光伏曝辐量的相比较优势。根据光伏组件的观测结果推算出各类型光伏组件的光伏反演辐照度,与气象辐射观测用总辐射表的总辐射辐照度趋势非常一致,在太阳能光伏主要利用时段相对误差基本在10%以内。     

A model for calculating hourly global solar radiation from satellite data in the tropics

A model for calculating global solar radiation from geostationary satellite data is presented. The model is designed to calculate the monthly average hourly global radiation in the tropics with high aerosol load. This model represents a physical relation between the earth-atmospheric albedo derived from GMS5 satellite data and the absorption and scattering coefficients of various atmospheric constituents. The absorption of solar radiation by water vapour which is important for the tropics, was calculated from ambient temperature and relative humidity. The relationship between the visibility and solar radiation depletion due to aerosols was developed for a high aerosol load environment. This relationship was used to calculate solar radiation depletion by aerosols in the model. The total column ozone from TOMS/EP satellite was employed for the determination of solar radiation absorbed by ozone. Solar radiation from four pyranometer stations was used to formulate the relationship between the satellite band earth-atmospheric albedo and broadband earth-atmospheric albedo required by the model. To test its performance, the model was used to compute the monthly average hourly global radiation at 25 solar radiation monitoring stations in tropical areas in Thailand. It was found that the values of monthly average of hourly global radiations calculated from the model were in good agreement with those obtained from the measurements, with the root mean square difference of 10%. After the validation the model was employed to generate hourly solar radiation maps of Thailand. These maps reveal the diurnal and season variation of solar radiation over the country.     

Solar radiation modeling and measurements for renewable energy applications: data and model quality

Measurement and modeling of broadband and spectral terrestrial solar radiation is important for the evaluation and deployment of solar renewable energy systems. We discuss recent developments in the calibration of broadband solar radiometric instrumentation and improving broadband solar radiation measurement accuracy. An improved diffuse sky reference and radiometer calibration and characterization software for outdoor pyranometer calibrations are outlined. Several broadband solar radiation model approaches, including some developed at the National Renewable Energy Laboratory, for estimating direct beam, total hemispherical and diffuse sky radiation are briefly reviewed. The latter include the Bird clear sky model for global, direct beam, and diffuse terrestrial solar radiation; the Direct Insolation Simulation Code (DISC) for estimating direct beam radiation from global measurements; and the METSTAT (Meteorological and Statistical) and Climatological Solar Radiation (CSR) models that estimate solar radiation from meteorological data. We conclude that currently the best model uncertainties are representative of the uncertainty in measured data.