OBTENÇÃO DE NANOFLUÍDOS À BASE DE NANOPARTÍCULAS DE MAGNETITA E FERRITAS DE COBALTO EM MISTURAS ÁGUA E PROPILENOGLICOL PARA UTILIZAÇÃO EM SISTEMAS DE REFRIGERAÇÃO

Abstract

Nanofluids are suspensions of nanomaterials in base fluids with thermal properties. These nanofluids can be based on oxide nanoparticles with thermal properties for cooling or refrigeration, suspended in fluids such as water, ethylene glycol or mineral oils, which have recently attracted attention due to the advantages and efficiency they present in heat transfer when compared to traditional conductive fluids in a wide range of microfluidics applications. The objective of nanofluids is to achieve the highest possible values of thermal properties at the lowest concentrations of nanoparticles. One of the main challenges in applying nanofluids in heat exchange devices is related to colloidal stability. The objective of nanofluids is to achieve the highest possible values of thermal properties at the lowest concentrations of nanoparticles. One of the main challenges in applying nanofluids in heat exchange devices is related to colloidal stability. In order to apply nanofluids in efficient heat exchanger devices, their adequate dispersion and high colloidal stability of the nanoparticles in the temperature range are essential, thus avoiding, in addition to the agglomeration and sedimentation of the nanoparticles in the base fluid, the corrosion, clogging and the effort of pumping. In this work we turn our attention to the synthesis of nanofluids based on iron oxide and cobalt oxide nanoparticles dispersed in water-propylene glycol mixtures for use in heat exchange systems.