Focuses of ICNf 2019 include production and characterisation of nanofluids and liquid-based nanocomposites, nanofluid-based heat transfer and storage of thermal energy, as well as industrial applications. Main topics include the following: -Nanofluid materials nanoparticles, nanoPCM, nanofluids, nanosalts, ionanofluids, etc. -Nanofluid preparation and characterization methods -Nanofluid properties thermophysical, optical, and magnetic properties -Heating, cooling, and refrigeration -Phase change -Storage of thermal energy -Solar energy applications -Numerical simulation -Industrial applications -Health, safety, and environmental issues