Paper presented to the 3rd Southern African Solar Energy Conference, South Africa, 11-13 May, 2015.
The optical efficiency of a parabolic trough collector is one
of the most important parameters that affect the performance of
the entire collector system. In this study, an optical and thermal
analysis of a parabolic trough collector system for different
slope errors and specularity errors is presented. For optical
analysis, the influence of slope errors, specularity errors and
system geometry on heat flux distribution on the receiver's
absorber tube is determined using Monte-Carlo ray tracing in
SolTrace. The ray tracing results are then coupled with a
computational fluid dynamics code to investigate the thermal
performance of the receiver. Results show that the slope and
specularity errors influence the heat flux distribution on the
receiver's absorber tube. The optical efficiency of the collector
is shown to reduce significantly as the slope errors increase and
slightly as specularity errors increase. The influence of slope
errors and specularity errors on the thermal performance of the
entire system is investigated numerically and presented.