The overall thermal performance of a Parabolic Trough Collector (PTC) depends on its\noptical performance, particularly the uniformity of the irradiance distribution and the resultant\noptical efficiency of the collector. Local Concentration Ratio (LCR), optical efficiency and average\nlight concentration are three fundamental parameters of the optical performance of a PTC.\nThese parameters are affected by various optical and physical factors. The effects of these individual\nfactors on the performance parameters were investigated in this study using a verified Monte Carlo\nray tracing optical simulation model. The investigation revealed that all three performance parameters\nare directly related to the optical properties of the collector components. The values decreased gradually\nwith the increase of focal length of the mirror. Uniformity of the LCR profile was observed to decrease\nwith increasing rim angle and geometric concentration. Defocus dislocation of the receiver was found to\nimprove the uniformity of the LCR distribution by decreasing its peak concentrations, Cmax. Off-focus\ndislocation of the receiver, and inward angular deviation of the mirror profile were observed to\nincrease the Cmax and decrease the uniformity of the LCR distribition. Out-focus dislocation of the\nreceiver and solar tracking error distort the bi-symmetry of a normal LCR profile.
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