2D-WS2 nanofluids as heat transfer fluid in concentrated solar power systems
Résumé
Nanofluids exhibit improvements in thermophysical properties such as thermal conductivity, isobaric specific heat or thermal diffusivity compared with conventional heat transfer fluids. For this reason, nanofluids are considered as a new generation of heat transfer fluids that are very appealing in many fields including solar energy. In this work, we have prepared nanofluids whose base fluid is the eutectic mixture of biphenyl
and diphenyl oxide that is typically used in Concentrating Solar Power (CSP) plants. The WS2 nanosheets used as nanomaterial
in the nanofluids confer great stability to suspensions, which is a key factor in the performance of nanofluids. The study of
rheological properties did not show any significant changes in viscosity and surface tension in nanofluids compared to the base
fluid. However, the most remarkable result is that nanofluids showed improvements in thermal conductivity of up to 30% and
in the heat transfer coefficient of up to 16%, compared to the base fluid. Ab initio molecular dynamics studies revealed a
dissociative adsorption of diphenyl oxide molecules on the WS2 edges, which can be expected to influence the rheological and
thermal properties of the nanofluids [1].