LAUSR

Abstract A plasmonic blended nanofluid formed by mixing Au nanoparticles with different shapes in water is proposed in this paper for direct solar absorption. Optical and thermal properties of the plasmonic blended nanofluid are studied numerically and experimentally. Resonant characteristics of Au plasmonic nanoparticles are tuned by particle shapes. Compared with single-component nanofluid, the extinction spectrum of this plasmonic blended nanofluid is broadened. The matching of extinction spectrum and solar radiation spectrum is tuned by adjusting the proportion of components in blended nanofluid. Photothermal properties of three types of plasmonic blended nanofluids are measured experimentally. Due to the higher extinction coefficient, the blended nanofluid exhibits higher temperature rise. A simplified heat transfer model is established to verify experimental results. Simulation results are consistent with experimental results. Before experiment, photothermal properties of different nanofluids can be qualitatively compared by using the simulation model, which can effectively reduce the number and cost of experiments.