Solar limb darkening and ray trace evaluation of solar concentrators

Abstract

A comparison of different correlations commonly used to describe the limb darkening effect is made. A somewhat new correlation is proposed which predicts the values to within ±1.5% of the experimental values. Using a conventional ray trace technique and assigning proper weight factors to each ray, the distribution of the local concentration ratio over a flat absorber placed in the focal plane of a cylindrical parabolic trough is also determined.