Three-Dimensional Optical and Thermal Numerical Model of Solar Tubular Receivers in Parabolic Trough Concentrators

Monte Carlo ray tracing, coupled to a finite volume solver, is used to model 3D heat transfer in a parabolic trough solar concentrator system. The nonuniform distribution of the incident solar radiation, the radiative exchange between the various receiver surfaces, and the heat gain/loss around the receiver's circumference and along the system's axis are determined for spectral radiative properties of the receiver and concentrator surfaces. The computed heat losses and thermal efficiencies agree well with experimental data. Besides the beneficial information on peak temperatures and heat flux, the 3D model is able to predict glass temperatures more accurately than previous gray models and temperature correlations. [DOI: 10.1115/1.4007494]