Numerical Investigation of the Effects of Nanoparticle Diameter on Velocity Field and Nanoparticle Distribution of Nanofluid Using Lagrangian-Eulerian Approach

This article studies the effects of nanoparticle diameter on the concentration distribution and velocity of nanoparticles in nanofluid are examined using Lagrangian-Eulerian. Moreover, the effects of nanoparticle diameter on the velocity of fluid phase affected by the particle movements are studied. In addition, the effects of the change of Brownian and thermophoretic forces with diameter on nanoparticles and fluid velocity as well as nanoparticles distribution are studied. The results indicate that particles are not uniformly distributed, as the concentration is higher in the vicinity of the pipe centerline than its wall. With the increase of nanoparticle size, the nanoparticle concentration in the vicinity of pipe wall is augmented. According to the results, with the increase of the nanoparticle diameter, the fluid and nanoparticle velocity is reduced. The reason for this is the reduction of Brownian forces with the increase of nanoparticle diameter.