Common coolants as water, oil or ethylene glycol are characterized by poor thermal properties, i.e. convective heat transfer and heat conductivity coefficient. Addition of solid particles with size less than 100 nm can significantly improve these properties. Stable suspension of nanometer particles behaves as fluid and hence are usually called – nanofluid. The goal of this work is to present results of investigations with the Cu – and Ag – ethylene glycol nanofluids. Experiments on heat transfer in the laminar flow regime in a circular tube (1.4 mm I.D.) were carried out for constant heat flux conditions. A naofluid was prepared by means of the one-step method in polyol-process with microwaves irradiation. The test tube was heated up by an electric heater generating heat flux of q=2000–30000 W/m2. The fluid and wall temperatures at various locations along the tube were measured by a set of thermocouples. Results were compared with those determined for the host liquid. The experimental data proved a strong influence of nanoparticles presence on heat transfer coefficient especially at entrance region. The results of this and further investigations may by utilized as a basis for designing of efficient cooling devices in computer or MEMS – systems.
Journal: TechConnect Briefs
Volume: 1, Nanotechnology 2008: Materials, Fabrication, Particles, and Characterization – Technical Proceedings of the 2008 NSTI Nanotechnology Conference and Trade Show, Volume 1
Published: June 1, 2008
Pages: 778 - 781
Industry sector: Advanced Materials & Manufacturing
Topics: Nanoparticle Synthesis & Applications