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- 实验方案
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Robust Janus fibrous membrane switchable infrared radiation properties for potential building thermal management application
摘要： Buildings heating and cooling consumes a large part of global energy, contributing to aggravating the global warming and energy crisis. It is strongly desired but still lacking in realizing heating and cooling functions within the same material without intensive energy input. Herein, a Janus thermal management membrane with trilayer structure has been prepared by using the ZnO nanorods array-coated cellulose (ZnO-NRs@cellulose), ultralong MnO2 nanowires (UL-MnO2-NWs) and silver nanowires (Ag-NWs) as building blocks. The ZnO-NRs@cellulose fiber layer with rough surface was fabricated by a hydrothermal progress based on the controlled growth of ZnO nanorods on cellulose surfaces. Subsequently, the hydrothermally synthesized UL-MnO2-NWs and Ag-NWs were filtered onto the ZnO-NRs@cellulose layer in turn, forming laminated Janus membrane. The Janus membrane exhibited asymmetric radiation properties on each side: the ZnO-NRs@cellulose side of the Janus membrane shows high solar radiation reflectivity and high infrared emissivity to minimize heat input from sun and enhance the heat dissipation in hot environment, while Ag-NWs side of that exhibits relatively high solar radiation absorption rate and low infrared emissivity for enhancing heat input from sun and reducing the heat radiation loss in cold environment. The introduction of UL-MnO2-NWs and Ag-NWs into the laminated Janus membrane endows the membrane with high tensile stress of 61.4 MPa. Moreover, the strong compatible entanglement among three layers of the Janus membrane causes the satisfactory interface stability. Due to the special asymmetric radiation performance, excellent interfacial compatibility, and high mechanical stability, such Janus membrane might be potential useful in building energy saving, personal thermal management and other facilities.
关键词： solar radiation,infrared radiation,laminated structure,MnO2 nanowire,Ag nanowire,Janus membrane
更新于2025-11-19 16:56:35
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Measurement and Investigation of the Incident Radiation in Case of Using Transparent Pyramidal Covers for Improving the Solar Panel’s Power Output
摘要： A new approach is presented to enhance the solar radiation intensity incident over the solar panel by using a transparent cover of pyramidal shapes. The pyramidal cover shape is manufactured of Polymethylmethacrylate dielectric material. The normal height of each pyramid is considered as a ratio of the base length. This ratio is considered in the present study to be 0.5, 1, and 1.5. The effect of the pyramidal covers on the solar panel voltage has been studied at different conditions. The experimental results confirm that the pyramidal cover shape causes the improvement to the solar panel output voltage by 4.2% when covering all the panel with pyramids of R=1 with a light incidence angle of 90 when the light rays come parallel to the panel surface. This improvement is found to decreases with covering fewer areas of the solar panel and with fewer incidence angles. It is found also that the distance between the light source and the panel is proportional to the output voltage improvement ratio compared to the panels output voltage without pyramidal cover. A mathematical model has been presented to prove the concept of increasing the electric and magnetic field of the incident radiation from the sun in case of presence of the transverse transparent barrier. Moreover, a mathematical ray tracking model was presented and validated with the experimental results by a maximum relative error of 14.8%
关键词： solar panel improvement,Incident radiation,enhancement of light field radiation,polarization,enhancement of solar radiation,transverse of transparent barrier
更新于2025-09-23 15:23:52
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[ACM Press the 3rd International Conference - Tetouan, Morocco (2018.10.10-2018.10.11)] Proceedings of the 3rd International Conference on Smart City Applications - SCA '18 - Empirical models for estimating the global solar radiation based on air temperature and sunshine duration
摘要： This work aims to develop and validate empirical models for estimating global solar radiation at site of Alhoceima based on the meteorological data measured during the period 2010-2017. The empirical models studied in this paper are broken down into two categories: the first category consist of linear and nonlinear regression which relates the monthly average daily global solar radiation to the sunshine duration, such as: the model of Angstr?m-Prescott, the cubic, quadratic model (Ogleman et al.), exponential (Almorox), logarithmic and power model. The second category consists of mathematical models calculating the monthly average daily global solar radiation based on the air temperature. And finally this study proposed model wish is based on sunshine duration and gives the best results for the city of Alhoceima. Statistical evaluation of the performance and accuracy of the models on the basis of The Root Mean Square Error (RMSE), Mean Bias Error MBE and R2 coefficient of determination, showed that all calibrated models estimates very well the monthly average daily global radiation. However the proposed model is more accurate with smaller errors and the best coefficient of determination.
关键词： air temperature,empirical model,sunshine duration,Daily global solar radiation,estimating global solar radiation
更新于2025-09-23 15:23:52
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Characterization of the solar climate in Malawi using NASAs surface meteorology and solar energy (SSE) model
摘要： This paper presents the characterization of global solar radiation (GSR) for Malawi using NASA’s SSE model. The mean monthly daily GSR monthly variation in the three regions of Malawi has been investigated. It has been found that there is a general gradient in GSR in the north-south direction. This gradient correlates well with the variation of the clearness index in the same direction (r = 0.986). It has been observed that the GSR is characteristic of each region. Simple analytic polynomials have been proposed for estimating solar radiation in the traditional Northern, Central and Southern regions of Malawi. There is a strong agreement between the polynomials and the SSE model with R2 values of 0.988, 0.989 and 0.989 and root mean square errors of 0.061, 0.057 and 0.062 kWh/m2.day for the regions, respectively.
关键词： surface meteorology and solar energy (SSE) model,global solar radiation,Malawi,solar climate
更新于2025-09-23 15:23:52
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Spline Cúbico para el Tratamiento Funcional de la Radiación Solar Global
摘要： The article shows the calculation of cubic splines that defines the behavior of the global solar radiation on a high Andean equatorial location. The spline smoothing is developed in a normed orthogonal functional space, where the discretized data (ti,xi) are transformed into functions X(t). The analysis of univariate and multivariate data allows studying natural phenomena from finite sets of numerical values. Data collection involves not only getting values, but also includes the processes or functions that give rise to them. Bootstrap resampling was used for detecting outliers with which annual, month and by climatic periods averages are obtained. Functional monthly averages of global solar radiation show the presence of two forms of behavior during the period studied.
关键词： functional data analysis,statistical analysis,global solar radiation,meteorological data,bootstrap,cubic spline
更新于2025-09-23 15:23:52
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Assessment of different combinations of meteorological parameters for predicting daily global solar radiation using artificial neural networks
摘要： In this study, for determining the best-input scenarios of the used parameters in predicting the Daily Global Solar Radiation (DGSR), a new approach based on Artificial Neural Networks (ANNs) was presented. The proposed approach is based on comparisons between all possible input combinations for determining the best scenarios that can give perfect correlations and approximations with DGSR. Recorded data from 35 stations belonging to different climatic zones (27 in Morocco and 8 in neighboring countries) were reported for training and testing the obtained results. The used input parameters include geographical coordinates, sun declination, day length, day number, clearness index (KI), Top Of Atmosphere (TOA), average ambient temperature (Ta), maximum temperature (Tmax), minimum temperature (Tmin), difference temperature (ΔT), temperature ratio (TR), relative humidity (Rh) and wind speed (Ws). The results revealed 128 best-input scenarios, where the first relevant input combination was found for KI, Ta, ΔT, TR and TOA. This result indicated that the best-input scenario for predicting DGSR is based only on three climatological parameters: KI, function of Ta f(Ta) and TOA. In addition, based on these found best-input scenarios and on the least square regression (LSR) technique, 128 new linear relationships between DGSR and the found best-input combinations were developed. The statistical analysis expressed through statistical criteria indicated perfect correlations and approximations between the predicted and measured values of DGSR.
关键词： Best scenarios,ANNs,Least square regression,Statistical analysis,Solar radiation modelling,Forecasting
更新于2025-09-23 15:23:52
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[IEEE 2018 International Multi-Conference on Industrial Engineering and Modern Technologies (FarEastCon) - Vladivostok, Russia (2018.10.3-2018.10.4)] 2018 International Multi-Conference on Industrial Engineering and Modern Technologies (FarEastCon) - The Increase of the Effectiveness of the Autonomous System of Solar Energy Supply
摘要： For the effective heat supply of the consumers the solar energy is viewed with the aim of replacing the organic fuel the costs on which constantly increase. The analysis of the existing solar collectors as the basic element of the system of solar heat supply and its factors for the increase of the effectiveness of its usage is shown. The interconnection of constructive and regime parameters of solar collectors and the necessity of the regulating the regime of their work for the effectiveness of the system of solar heat supply as a whole are also shown. To achieve the formulated purpose the regulating of the scheme of the connection of solar collectors between them is offered and as the source of power supply the solar battery is suggested for providing the autonomy of the system of solar heat supply. The principle of the control of the scheme of the connecting of solar collectors and the description of the regime of work of the suggested device are examined. The block scheme of the algorithm of control for providing the given parameters of regulating is worked out and shown.
关键词： system of solar heat supply,parameters of solar collector,algorithm of control,scheme of the connection of the collectors,solar collector,solar battery,solar radiation
更新于2025-09-23 15:22:29
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Solar radiation exergy and quality performance for Iraq and Turkey
摘要： The present study is conducted with two primary objectives: First, a new formulation for the maximum efficiency of the solar radiation conversion is developed by considering the radiative energy transfer between two surfaces at different temperatures for a constant volume system. Second, a new methodology is introduced for estimating the exergy value of the monthly average daily horizontal global radiation, including many parameters, such as monthly average daily value of the horizontal extraterrestrial radiation, the number of sunny hours, the day length, the mean temperature and the mean wind velocity. Seven statistical parameters are used to validate the accuracy of all models. The results of the two new models are found to be more reliable than the results obtained from other models. This study, which was conducted for four locations in Iraq and Turkey. The findings would help in predicting the maximum availability of solar radiation based on weather parameters.
关键词： empirical models,solar radiation,solar radiation exergy
更新于2025-09-23 15:22:29
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Global Solar Radiation Prediction Using Hybrid Online Sequential Extreme Learning Machine Model
摘要： Accurate global solar radiation prediction is highly essential for related research on renewable energy sources. The cost implication and measurement expertise of global solar radiation emphasize that intelligence prediction models need to be applied. On the basis of long-term measured daily solar radiation data, this study uses a novel regularized online sequential extreme learning machine, integrated with variable forgetting factor (FOS-ELM), to predict global solar radiation at Bur Dedougou, in the Burkina Faso region. Bayesian Information Criterion (BIC) is applied to build the seven input combinations based on speed (Wspeed), maximum and minimum temperature (Tmax and Tmin), maximum and minimum humidity (Hmax and Hmin), evaporation (Eo) and vapor pressure deficiency (VPD). For the difference input parameters magnitudes, seven models were developed and evaluated for the optimal input combination. Various statistical indicators were computed for the prediction accuracy examination. The experimental results of the applied FOS-ELM model demonstrated a reliable prediction accuracy against the classical extreme learning machine (ELM) model for daily global solar radiation simulation. In fact, compared to classical ELM, the FOS-ELM model reported an enhancement in the root mean square error (RMSE) and mean absolute error (MAE) by (68.8–79.8%). In summary, the results clearly confirm the effectiveness of the FOS-ELM model, owing to the fixed internal tuning parameters.
关键词： global solar radiation,West Africa region,energy harvesting,FOS-ELM model,input optimization
更新于2025-09-23 15:22:29
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[IEEE 2018 International Ural Conference on Green Energy (UralCon) - Chelyabinsk (2018.10.4-2018.10.6)] 2018 International Ural Conference on Green Energy (UralCon) - Comparative Analysis of Approaches to Consider Rationale of use of Solar Panel Plants for Power Supply of Off-Grid Consumers
摘要： The values of solar radiation for different monitoring periods from reference books were compared with calculated values from recent data of meteorological stations. The choice of meteorological stations depended on the differences of their latitude location, their position in the zone of the off-grid power supply, available data in different reference books on solar potential of the stations under study and presence of power plants located in different latitude zones using power resources for energy generation. The Sakha Republic (Yakutia) corresponded to these conditions. The comparative analysis of the initial values of solar potential showed that deviations amounted to 5–10%. The authors compared the results of recalculation of solar radiation values on the inclined surface using two approaches and showed the advantages of these approaches. They also investigated how the application of different approaches affected the optimal power of solar panel plants and calculated the payback periods of their construction. The payback period of the existing solar panel plants on the territory of the Sakha Republic (Yakutia) was compared with the calculated one. The application of different methodological approaches at different stages of rationale of solar panel plant construction was efficient for the power supply of off-grid consumers. It was proved that a simplified approach was reasonable for investigations of economic viability of power potential use on the territory under study. Detailed calculations are necessary for the determination of technical and economic parameters of a solar panel plant in a concrete settlement and for the estimation of economic effectiveness of its construction taking into account recent meteorological data.
关键词： recalculation on an inclined surface,optimal power,deviation of values,Solar radiation,payback period
更新于2025-09-23 15:22:29