Search results for "Vertical surfaces"
showing 3 items of 3 documents
UV Index experimental values on vertical surfaces
2011
UV erythemal irradiance (UVER) has been studied on a horizontal plane and on vertical surfaces with different orientations in Valencia, Spain. The evolution of the solar noon value and the maximum daily value over a year has been analysed from the instantaneous UVER taken every five minutes on the horizontal plane and on vertical surfaces with north, south, east and west orientations. The annual evolution of these values shows a sinusoidal form for all planes except for the vertical south plane with maxima in spring and autumn. The UV Index (UVI) on these planes was also determined. The percentage of coincidence of the UVI at solar noon and of the maximum daily UVER values, considering diff…
Evaluation of models for estimating solar irradiation on vertical surfaces at Valencia, Spain
1991
Abstract Hourly irradiation data recorded on vertical surfaces at north, east, south, and west orientations during the winter period going from December 1989 to March 1990 in Valencia, Spain, have been compared with estimated solar irradiation from several tilted-surface models. The isotropic-, Temps' and Coulson's-, Klucher's-, Hay's-, Skartveit's and Olseth's-, Gueymard's- and Perez' (simplified) models have been considered for this comparison. Root-mean-square-difference (RMSD), mean-bias-difference (MBD) and mean-absolute-difference (MAD) estimators have been used to measure the departure of models from experimental data. Modeled values are evaluated with the original coefficients propo…
The optimisation of the angle of inclination of a solar collector to maximise the incident solar radiation
1999
Abstract Irradiation data, recorded on vertical surfaces facing north, south, east and west and on a horizontal surface every ten minutes during daylight hours from January–December 1992 in Valencia, Spain, have been compared with estimated solar irradiation from inclined-surface models. Results show that Hays model most accurately reproduces the variation in irradiation on all vertical surfaces. Hays model has been used to find the hourly variation in the optimum tilt angle for a South-facing solar collector in Valencia, Spain, and also to calculate the yearly average of this angle. This method has been compared with the results provided by another model that uses average monthly values of…