Calculation of aerosol optical depth in solar radiation for different meteorological conditions

Abstract

A multitude of concentrating solar thermal power projects are currently being developed or proposed in many countries. Direct normal irradiance has an important impact on the optical-thermal conversion efficiency and rate of the plants. Though many researches focus on solar radiation, there are not many to emphasize variable air quality in different meteorological conditions. In this paper, aerosol optical depth of the atmosphere based on four wavelengths for three meteorological conditions in China has been experimented. To obtain solar radiation, two researches have been investigated as follows: the one is to calculate turbidity coefficients of the atmosphere according to Angstrom Law for different spectral aerosol optical depths, and another is to calculate the distribution characteristics of aerosol particles in the atmosphere and aerosol optical depths for the broadband using inversion method of experimental data. The results showed that the average value of turbidity coefficients for a clear day has a minimum of 0.9032 and the standard deviation has a maximum of 0.2870. The results also showed that the sizes of aerosol particle and aerosol optical depths for the broadband based on experimental values are different. The results can provide a reference to accurately calculate solar radiation.