Prediction of Global Solar Radiation on A Horizontal Surface Using Angstrom Model
Bahjat Hassan Alyas, Ahmed Mustaffa Saleem, Asmaa Taha Hussein
Northern Technical University, Technical Engineering College-Mosul, Iraq
Corresponding Author Email: [email protected]
This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
In this study, the average monthly global solar radiation on a horizontal surface is developed to provide a simple correlation for two Iraqi sites (Rutba and Mosul). At a five-year interval (2004-2008), on flat surfaces in two Iraqi cities, a monthly average global solar radiation and sunshine duration were measured. To estimate global radiation from the sunshine hour for these cities, a linear mathematical correlation represented by (Angstrome correlation) was applied on each month’s specific day in the tables (2 and 3). Two different (quadratic and polynomial) models of mathematical correlations have been compared to the model. The models obtained have a high coefficient of regression and fit the values best. In this study, the average monthly diffuse daily and radiation from the global radiation measured on the horizontal surface has been estimated. This study compares diffuse solar radiation for Rutba and Mosul with the results studied by Dr Waleed et al. . For Rutba and Mosul, the monthly maximum values of diffuse solar radiations have been achieved in the summer months, with values ranging from 5.99-9.56 (M.J./m2. day) to minimum levels December and January with a range of values 2.92 – 4.49 (MJ/2 m2. day).