Numerical investigation of direct absorption solar collectors based on carbon black nanofluids.

A novel model of a rectangular direct absorption solar collector (DASC) based on carbon black (CB) nanofluids for concentrated solar power is presented herein. Distributions of temperature, velocity, volume fraction of nanofluid were analyzed as well as the effect of CB concentration. A mesh independence study was also conducted. The results show that the optimal temperature and efficiency were, respectively, 331.669 K and 0.7234, for the concentration of 0.05 wt. %. The main reason was that higher concentration of CB formed a "shield" that blocked the light. The distribution of temperature and velocity of the nanofluid, and the volume fraction of carbon black during the flow process were highlighted. The study reveals that the nanoparticle has huge potential to improve the efficiency of DASC. [ABSTRACT FROM AUTHOR]