Modeling direct steam generation in solar collectors with multiphase CFD

The direct steam generation in parabolic-trough solar collectors, using water as heat-transfer fluid, is an attractive option for the economic improvement of parabolic trough technology for solar thermal electricity generation in the multi megawatt range or industrial process heat supply. But the existence of single-phase and two-phase flow in the absorber pipes of the solar collectors constitutes a challenge for the development of simulation tools and process control schemes suitable for this type of solar technology. The computational fluid dynamic package STAR-CCM+ is used to implement an efficient multiphase model capable of simulating the behavior of direct steam generation in parabolic-trough solar collectors. This work describes the modeling approach and summarizes the comparison of simulation results with the measurements taken at a direct steam generation solar test facility located at the Plataforma Solar de Almeria, Spain. (C) 2013 Elsevier Ltd. All rights reserved.