Flow and heat transfer behaviors of water-based nanofluids confined in nanochannel by molecular dynamics simulation

The present work reports a molecular dynamics simulation on the flow and heat transfer behaviors of water-based nanofluids confined in a nanochannel. The Brownian motion of nanoparticles in the base fluid is analyzed. Rotational velocity of nanoparticle is found to be in the range of 1×10⁹~1×10¹⁰ rad/s. Translational velocity of nanoparticles is calculated by MD simulation to be approximately 10m/s. By means of rotational and translational Peclet number the effect of nanoparticle movements for heat transfer augmentation with nanofluids have been verified. It is also found that the local velocity and temperature of nanofluids near the fixed wall is evidently higher than that of base fluid, which indicates the velocity gradient and temperature gradient of nanofluids near the fixed wall is greater than those of single-phase base fluid. The change of nanofluid velocity and temperature profiles is attributed to the high-speed micro-motions of nanoparticles.