SÉRIES DIURNA E ANUAL DA RADIAÇÃO DIRETA NA INCIDÊNCIA NORMAL EM BOTUCATU, PERIODO DE 1996 A 2005
DOI:
https://doi.org/10.59627/cbens.2008.1351Keywords:
Direct solar radiation, regression modelling, BotucatuAbstract
In this work, the seasonal variation is analyzed and a fourth order polynomial model was developed to estimate the diurnal evolution of direct solar radiation at the surface using measurements carried out from 1996 to 2005 in Botucatu, São Paulo, Brazil. This analysis indicated that mean hourly values varied between 2.20 MJ m-2 to 1.77 MJ m-2. The fourth order polynomial derived by linear regression was able to simulate the hourly values with coefficient of determination of 0.99867. The validation indicated that MBE equal to 1.0%, a RMSE equal to 3.7% and index of agreement equal to 0.9980. These statistical parameters indicate that model overestimates observations and show a very low level of statistical dispersion. Discrepancies are attributed to climate variations.
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References
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