University of TehranJournal of Solar Energy Research2588-30971220161001Proposition of Housing Construction with Solar Envelope Method in Renewal Area After Disaster636862292ENF.CananSelcuk University, Faculty of Architecture, 42031, KONYA, TURKEY.G.ÖzerSelcuk University, Faculty of Architecture, 42031, KONYA, TURKEY.F.K.VarolgüneşBingöl University, Faculty of Architecture And Engineering, BİNGÖL, TURKEY.Journal Article20170715In this study, with using the method of solar envelope, general layout plans, building forms and building density values were obtained to ensure optimal utilization of the sun in mass housing area. Toki housing in İnonu Quarter of Bingöl city who faced constantly with the fact earthquakes and natural disasters throughout the history was selected as study area. In conclusion; assessments were carried out about current buildings situation and recommended building forms.<br /> https://jser.ut.ac.ir/article_62292_3236d1fd577057ded2257aee87ab8253.pdfUniversity of TehranJournal of Solar Energy Research2588-30971220161001Absorptance of Different Local Coated Surfaces to Global Solar Radiation in Egypt182462296ENH.GadMansoura University, 35516, EgyptS.El-GayarAgric. Eng. Res. Inst., A. R. C, Giza, 256, EgyptH2.GadMansoura University, 35516, EgyptJournal Article20170717The absorptance of different oil painted surfaces to total solar radiation depends mainly on their color. The surface coating color of buildings, greenhouses, mulchs and absorbers (solar collectors) affect the amount of absorbed total solar radiation. The surface is heated much when its absorptance has a higher value and vice versa. To test the absorptance of 11 coated surfaces and one sheet without color, an experimental setup to measure the surface temperature is designed and installed at Mansoura University, Egypt. The absorptance of these locally coated surfaces is calculated. Results have shown that, (G.I) sheets coated with black bored (Bb), polish black (Pb), brown (Br), red (R), violet (V), green (G), blue (Blu), G.I. sheet without color, dark yellow (Yd), yellow (Y), silver (S) and white (W), are 0.92, 0.886, 0.881, 0.852, 0.844, 0.824, 0.823, 0.794, 0.782, 0.777, 0.716 and 0.661 respectively.https://jser.ut.ac.ir/article_62296_5e853fae52489b615215d369e2cac1ec.pdfUniversity of TehranJournal of Solar Energy Research2588-30971220161001Optimum Tilt Angle and Maximum Possible Solar Energy Gain at High Latitude Zone253562297ENS.SoulaymanHigher Institute for Applied Sciences and Technology, Damascus, P. O. Box 31983, Syria.Journal Article20170717The performance of a solar collector is highly dependent on its tilt angle with the horizon. The variation of tilt angle changes the amount of solar radiation reaching the collector surface. Meanwhile, is the rule of thumb, which says that solar collector should be orientated towards the Equator with a tilt equal to latitude, is valid for high latitudes region? Thus, it is required to determine the optimum tilt for Equator facing collectors. In addition, the question that may arise: how many times is reasonable for adjusting collector tilt angle for Equator facing collectors? A mathematical model was used for estimating the solar radiation on a tilted surface, and to determine the optimum tilt angle and orientation (surface azimuth angle) for the solar collector at any latitude. This model was applied for determining optimum tilt angle in the high latitudes zone in the Southern and Northern Hemispheres, on a daily basis, as well as for a specific period. The optimum angle was computed by searching for the values for which the radiation on the collector surface is a maximum for a particular day or a specific period. The solar radiation on the collector surface of optimum tilt angle, of latitude tilt angle and of null tilt angle was calculated for a particular day or a specific period. The results reveal that changing the tilt angle 12 times in a year (i.e. using the monthly optimum tilt angle) maintains approximately the total amount of solar radiation near the maximum value that is found by changing the tilt angle daily to its optimum value. This achieves a yearly gain in solar radiation up to several times of the case of a horizontal surface depending on the latitude value.https://jser.ut.ac.ir/article_62297_68a37dabb8b03418c6bce65df0ade163.pdfUniversity of TehranJournal of Solar Energy Research2588-30971220161001Photoelectrochemical Hydrogen Generation in Coral-like TiO2 Photoanode363962298ENA.BayatDepartment of physics, Faculty of Basic Science, Tarbiat Modares University, Tehran, Iran.E.Saievar-IranizadDepartment of physics, Faculty of Basic Science, Tarbiat Modares University, Tehran, IranJournal Article20170717The coral-like TiO<sub>2</sub> nanoparticles were synthesized on the transparent FTO conductive substrate and their photovoltaic properties investigated under illumination. Coral-like TiO<sub>2</sub> photoanodes were synthesized using a hydrothermal method and annealed at 450 ˚C to obtain better crystallinity. Annealed coral-like TiO<sub>2</sub> show a photocurrent enhancement of ~50% compared to pristine coral-like TiO<sub>2</sub> without annealing using 1M Na<sub>2</sub>SO<sub>4</sub> as electrolyte at potential of 0 V.https://jser.ut.ac.ir/article_62298_87c62985cb5b93aab748ea03f38cfb74.pdfUniversity of TehranJournal of Solar Energy Research2588-30971220161001Experimental and Numerical Analysis of Ambient Crosswind Effects on a Floating Solar Chimney Power Plant Performance404662299ENM.R.LarkiaDepartment of Mechanical Engineering, Amirkabir University of Technology (Tehran Polytechnic), 424, Hafez Ave., Tehran-Iran.A.ArefianDepartment of Mechanical Engineering, Amirkabir University of Technology (Tehran Polytechnic), 424, Hafez Ave., Tehran-Iran.R.H.AbardehDepartment of Mechanical Engineering, Amirkabir University of Technology (Tehran Polytechnic), 424, Hafez Ave., Tehran-Iran.Journal Article20170717Floating solar chimney (FSC) power plant is a novel kind of solar thermal technologies which uses the buoyant airflow and chimney (stack) effect to make an artificial airflow and generate electricity from aero-turbines. Also FSC has the capability of economic competition with conventional and other renewable power plants. Considering the FSC structure, it is obvious that, ambient cross wind (ACW) has significant influence on the FSC performance. The main purpose of this study is an investigation on the effect of ACW on updraft airflow inside a FSC which is a considerable parameter on system performance. In addition, FSC operation has been analyzed at different tilt angles when exposed to external crosswind. Hence, a geometrical model consisting of FSC and its surrounding ambience is simulated and mathematical model is proposed to demonstrate the fluid flow, heat transfer and performance of entire system are further developed. The variation of FSC updraft velocity is analyzed in different ACW velocities. In this research, design and construction of a small-scale (laboratory model) floating solar chimney is performed and numerical results are verified with experimental setup data. Analysis of numerical simulation indicates that when the ACW is relatively weak, it will deteriorate the updraft air flow velocity of fixed solar chimney or vertical floating chimney due to the tip vortices effects. Increasing the tilt angle of the floating chimney causes a decrease in tip vortices formation and finally make a considerable improvement in updraft velocity compared to the fixed (vertical) chimney. Although inclination of the floating chimney decreases the physical height, the performance of FSC is better than fixed type due to the reduction of the tip vortices effect in windy conditions. The present work can be useful to predict the performance of large-scale FSC by considering the influence of ACW.https://jser.ut.ac.ir/article_62299_13605cfa3cd16254e93ae3fa055c4187.pdfUniversity of TehranJournal of Solar Energy Research2588-30971220161001Thermal Modelling of a Solar Air Heater for All Over the Year of Yazd Province475262300ENH.SafariSchool of Mechanical Engineering, Yazd University, Yazd-Iran.A.DehghanSchool of Mechanical Engineering, Yazd University, Yazd-Iran.Journal Article20170717Solar collector, the first part of each solar dryer system, is important for industrial and agricultural purposes. The final objective of any solar system is to maximize its output. The energy analysis is excellent complementary thermodynamic tools for this purpose. In the present study, a comprehensive thermodynamic model for energy analysis of a double pass solar air heater has been carried out. Energy balance equations have been investigated for all components of the solar air heater including insulation, lower channel air stream, absorber, upper channel air stream and glass cover. The main object of this research was to find energy efficiency of a double- pass solar air heater for all over the year of Yazd Province in Iran. Moreover, the effect of inlet length and inlet width of collector on outlet temperature of solar air heater was studied. The results of the simulation showed that the maximum monthly average energy efficiency of the solar air heater is 32.41% in January with 145solar radiations. It is attributed to the fact that the inlet length of solar air heater has a positive effect on the increment of outlet temperature of top and bottom channel and efficiency of system, also the inlet width of solar air heater has negative effect.https://jser.ut.ac.ir/article_62300_688a7a9a21e8d28592fe4cb18be9213c.pdf