Geometric analysis of three-dimensional effects of parabolic trough collectors

An analytical approach, as an extension of one newly developed method – First-principle OPTical Intercept Calculation (FirstOPTIC)– is proposed to evaluate the geometrical impact of three-dimensional (3-D) effects on the optical performance of parabolic trough collectors. The mathematical steps of this analytical approach are presented and implemented numerically as part of the suite of First- OPTIC code. The new code has been carefully validated against numerical solutions and ray-tracing simulation results. The FirstOPTIC code is then applied to a series of case studies to examine the impact of some important 3-D effects on the intercept factor. A significant result of this work is the correction of the approach generally accepted for the specularity mirror errors for non-zero incidence angles. The new correlation has been validated using the FirstOPTIC approach and ray tracing. 2012 Published by Elsevier Ltd