ESTIMATION OF HOURLY GLOBAL SOLAR RADIATION IN EGYPT USING MATHEMATICAL MODEL

Document Type : Original Article

Author

Agricultural Engineering Department, Faculty of Agriculture, Minoufiya University, Shebin El-Kom, Egypt

Abstract

The main purpose of this paper is to develop a computer mathematical model which produces estimates of hourly average total solar radiation flux incident on the earth's surface under climate conditions of Delta, Egypt. Predictors for solar radiation have been developed because there is often a lack of representative solar radiation data in most countries. Cloudiness, atmospheric transmissivity, latitude and orientation of the Earth relative to the Sun, time of day, slope and aspect of the surface determine the spatial and temporal distribution of irradiance  incident on a surface. Measured data were collected from the Solar-Meteorological stations of Agricultural Engineering Department at El-menoufiya University, El-Mansoura university and Belbees,  in order to evaluate the present model. A comparison study between measured and predicted data has been carried out based on the main bias error and correlation coefficient. It can be concluded that the present model can be used to estimate the hourly average total solar radiation for El-menoufiya, El-Mansoura, and Belbees with an excellent agreement

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Main Subjects


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