From lab and up : superior and economic heat transfer performance of ionanofluids containing long carbon nanotubes and 1-ethyl-3-methylimidazolium thiocyanate

Abstract

The optimization of energy systems and the efficiency enhancement of energy conversion processesare still huge challenges. The ionanofluids (INFs) composed of the long multi-walled carbon nanotubes(MWCNTs) and 1-ethyl-3-methylimidazolium thiocyanate ionic liquid ([C 2 C 1 im][SCN]) are innovative sys- tems with proven remarkably enhanced thermal conductivity and attractive rheological characteristics.Therefore, as an extension of our previous study, this work aims to examine the overall heat transfer per- formance of these INFs as working fluids for energy conversion processes and design sustainable energysystems. The new measuring set was designed and constructed to determine the convective heat transfercoefficient and pressure drop during the flow of INFs, using the heat exchanger with saturated steam at100 °C. The obtained results showed that the heat transfer of INFs is prevailed by the convection mecha- nism. According to a new thermo-economic efficiency-price index proposed in this work, the amalgama- tion of MWCNTs with [C 2 C 1 im][SCN] is justified from both thermophysical and economic points of view.