Nanofluids synthesis based on copper nanoparticles and silver nanostructures core@shell for applications as heat exchangers fluids

Abstract

Nanofluids containing bimetallic nanoparticles of copper and silver, and core@shell nanostructures of copper@silver stabilized with polyethylene glycol are proposed to be investigated. The investigation is based on colloidal stability and thermal properties to understand the role of nanofluids used in heat exchangers efficience. Nanofluid was defined as consisting of nanoparticles dispersed in conventional fluid refrigerant providing thermophysical properties to improve heat transfer of the cooling fluid. Suspended metallic or metal oxides nanoparticles in fluids such as water, ethylene glycol and mineral oils nanoparticles add efficiency to the heat transfer of these fluids. The nanofluids have recently attracted great attention due to the benefits and efficiencies that present in heat transfer compared to traditional conductive fluids in a wide range of applications in microfluidics. The goal of nanofluids is to reach the largest possible values of thermophysical properties of fluids with reduced concentrations of nanoparticles. The need for efficient temperature control of heat exchangers devices added to the trend of products miniaturization has led to the search for alternatives that reduce energy costs by generating a favorable field for research in technological applications and basic research in the production and colloidal nanofluids stabilization of nanostructured particles (core@shell). A key challenge in applying the nanofluids as heat exchanger liquid is directly related to colloidal stability at high temperature. For best efficiency and thermal properties of the nanofluids heat exchanges are essential for adequate dispersion and high colloidal stability of the nanoparticles in the range of working temperature, thus suppressing the agglomeration and sedimentation of fluid nanoparticles, besides avoiding such as corrosion, clogging and pumping effort.Key words: nanofluids, colloids, nanoparticles, thermal conductive. (AU)