Abstract:
In this study, a new combined model presented to study the flow and discrete
phase features of nano-size particles for turbulent convection in a horizontal
tube. Due to the complexity and also many phenomena involved in particleliquid
turbulent flows, the conventional models are not able to properly predict
some hidden aspects of the flow. Therefore, Brownian motion is implemented
in discrete phase model to predict the migration of the particles as well as
energy equation has modified for particles. Then, the final results are exported
to the mixture equations of the flow. The effects of the mass diffusion due to
thermophoresis, Brownian motion and turbulent dispersion are implemented as
source terms in equations. The results are compared with the experimental
measurements from literature and are adequately validated. The accuracy of
predicted heat transfer and friction coefficients are also discussed versus
measurements. The migration of the particles toward the centre of the tube is
properly captured. The results show the non-uniform distribution of particles in turbulent flow due to strong turbulent dispersion. The proposed combined
model can open new viewpoints of particle-fluid interaction flows.
