With the increasing demand for cooling systems for electronic devices, nanofluid-microchannel heat sinks (MCHSs) have emerged as a hot topic. However, solving the problem of nanoparticle deposition is key to bringing this technology to an industrial scale. Traditional research focuses on the chemical characters of stationary nanofluids. However, thermophysical factors also affect the deposition of flowing fluid. In order to analyse thermophysical characteristics of an Al2O3-water nanofluid in a straight microchannel, Brownian force was simulated using a discrete phase model (DPM). The results indicate that Brownian motion has a great impact on particle deposition. However, the influence of temperature on the mean free path could be ignored for nanofluids in the MCHS. The deposition rate decreased with increasing particle diameter, but the deposition rate reduced as the velocity increased. These results have a guiding significance when designing new microchannel structures and inform the best conditions to reduce deposition.
Keywords Nanofluids, MCHS, DPM, Deposition