The composition development and the heat transfer investigation of zinc oxide nanofluids

Abstract

Many industrial processes involve heat removal by means of cooling devices. In particular, the problem of the temperature control has become crucial in high heat fluxes applications, such as nuclear fission plants and systems for micro/nano power electronics (MEMS/NEMS). Nanofluids represent diluted suspensions of nanoparticles with a diameter of less than 100 nm. The pre-sent study is devoted to the liquid composition consists of zinc oxide nanoparticles (ZNP) in tetraethylene glycol (PEG200)/kerosene (KO25) base fluid. Zinc oxide nanoparticles samples were obtained by sol-gel technique using ZnX (II) 3 SO , , AcO    as precursor, followed by calcination of Zn(CO 3 ) y (OH) x at 300–400 °C. Preparation methods of 0.5–3 wt.% ZnO/10–40 vol.% PEG200-KO25 nanofluids have been developed using zinc oleate (1–3 wt.%) as a dispersant. The observed thermal conductivity were measured using self-constructed experimental setup. An equilibrium temperature ( Т eq ) established as a result of heat transfer to a medi-um and constant heating process. That parameter used to describe observed thermal conductivity. The lower viscosity of the prepared nanofluids leads to a greater observable thermal conductivity at auto-convection mode ( Т eq = 49.7–52.5