Abstract:
In this research Lagrangian method is employed to track
the nanoparticles inside a differentially heated walls nanofluidfilled
cavity in natural convective flow. The thermo-physical
properties of the solid-liquid mixture is also included in
Eulerian frame. There are multiple interactions between fluid
and particles which turns the simulations for solid-liquid highly
complicated. ANSYS FLUENT 15.0 was used in this research
to model submicron particles. Moreover, important interaction
forces are implemented in the software as a User Defined
Function (UDF) to modify the Lagrangian model. Brownian
movement of the particles is assumed as a diffusion force acting
on each particle during small user defined time step. Pressure
gradient, gravity, virtual mass and Thermophoresis forces have
also added to the force balance equation. Electrostatic forces
are the contributing factors for stability of the nanofluid which
they are needed to be present in dynamic equation of the
particles. The importance of the forces on distribution of the
particles is compared. The results show that the presence of
these forces has considerable impact on nanoparticles
concentration profiles.
Description:
Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016.
