Performance analysis of parabolic trough solar collector

In this paper, the heat flux distribution on the outer surface of a the absorber tube of a parabolic solar collector receiver is simulated by Monte Carlo Ray-Trace Method (MCRT). Nonlinear heat flux distribution is considered as complex boundary condition used in FVM to simulate the coupled heat transfer problem. To investigate the concentrating characteristics, the finite size of sun is considered, and the effects of geometry concentration ratios and rim angles on sun radiation heat flux distributions are also analyzed. Temperature-dependent properties of the oil and thermal radiation between the absorber tube and the outer glass cover are also taken into account. Numerical results show that the predicted results agree well with the data in reference, which proves that the models and methods are feasible. The finite size of sun has significant influence on the heat flux distribution on circle direction, but little influence on the distribution on axial direction. With increasing geometric concentration ratios, the angle span of reducing area becomes larger. With increasing rim angle, the heat flux distribution curve moves towards the direction of circle angle 90° and the maximum value of heat flux density reduces. The convection and maximum temperature difference on the wall of the receiver inner tube are largely influenced by the inlet velocity, inlet temperature and the temperature-dependent properties of the oil, with almost the same direct normal irradiance.