Sedimentation Study and Dispersion Behavior of Al₂O₃–H₂O Nanofluids with Dependence of Time

Nanofluids are kind of engineering material, with a new challenge for thermal sciences provided by nanotechnology. Nanofluids are being investigated for numerous applications, including cooling process, manufacturing process, chemical process pharmaceutical process and medical treatment process etc. Nanofluids are basically the suspension of solid nanoparticles with size typically 1–100 nm in base fluid. In current research, Alumina size less than 50 nm has been used. The tested fluids have been prepared by dispersing Al₂O₃ into DI water at three different conditions by using 1 wt%, 3 wt% and 5 wt%. concentrations of alumina without using any surfactant. To ensure the quality of dispersion and stability of alumina nanoparticles in DI water, an ultrasonicator with 47 kHz frequency and dispersion time until 3 hrs has been used. Particle sedimentation test of these different condition nanofluid samples has been critically checked. As per result, after 30 days approximately 28% particle sedimentation recorded in 3 wt% and 21% sedimentation recorded in 5 wt% Al₂O₃ nanofluid, prepared with 3 hrs ultrasonicator dispersion time. Also the particle size (PSS) result for 3 wt% and 5 wt% Al₂O₃ nanofluid with dispersion time 3 hrs got as 46 nm and 60 nm respectively. The present research will be helpful to investigate the dispersion behavior of different condition water-based Al₂O₃ nanofluid with respect to time without using any using any surfactants or any other surface additives to use further in heat transfer processes.