Mathematical Modeling and Numerical Analysis of Thermal Distribution in Arch Dams considering Solar Radiation Effect

Table 1

Summary of the important angles in solar radiation problems.

Symbol	Name	Definition
𝜑	Latitude	The angular position of the given surface to the equator
𝛿	Declination	The angular position of the sun at the solar noon to the equator
𝛽	Slop	The angle between the given surface to the horizon
𝛾	Surface azimuth angle	Illustration diversion of surface normal vector on the horizontal plane to the south latitude
𝜔	Hour angle	The angular distance of the sun’s east and west to origin meridian due to earth rotation in rate of 15 degrees per hour around its axis
𝜃	Angle of incident	The angle between the direct radiation on the surface and its normal vector
𝜃𝑧	Zenith angle	The angle between the vertical line and the line along the sun
𝛼𝑠	Solar height angle	The angle between sun and horizon
𝛾𝑠	Solar azimuth angle	The angular distance between the geographic southern and the sun illustration on horizon