Development of a nano-heat transfer fluid carrying direct absorbing receiver for concentrating solar collectors

A MATLAB-based computer model to design a novel directly absorbing receiver system (DARS) for concentrating solar collectors employing nanofluid-based solar radiation volumetric absorption is presented. Graphene and aluminum nanosphere-based suspensions in Therminol VP-1 were simulated to identify the optimum thermo-geometric configuration of a DARS comprising a transparent all glass tubular absorber. Several particle concentrations were simulated scrutinizing the optical response of the two colloidal dispersions to yield a minimum supply temperature of 250 degrees C; further investigated are the implications of fluid flow velocity upon system yield. The resulting temperature fields and geometric dimensions of the DARS are predicted. Findings demonstrate that the DARS is able to deliver heat at similar to 265 degrees C with a receiver tube diameter of 5 mm opposed to commercially available 70-mm diameter metallic absorbers.