This paper is concerned with the interaction between nanoparticles in buoyancy-driven flow. The nanoparticles suspended in a base liquid are driven to stochastic motion by rapidly fluctuating forces, this phenomenon is termed as 'thermal dispersion' resulting from the dissociation of the ambient solvent molecules taking place within the mixture. Such thermal dispersion is esteemed to play an aggressive role in the increase of energy exchange rates in the fluid. Under the influence of these forces, the suspended nanoparticles may experience interparticle collision and attachment of the colliding particles and form aggregates. The theme of the present work is to understand the thermal transport phenomena of buoyancy-driven nanoparticles as well as to analyze the enhancement mechanism of energy transport from the nanoparticles. By considering physical properties of both the base fluid and the nanoparticles, as well as the structure of the nanoparticles and aggregates, a mathematical model has been developed to predict the axial velocity and temperature of both the fluid and the nanoparticle arbitrarily moving inside the system. The model proposed is a two-equation model, one for the fluid and the other for the nanoparticles, which are later combined together to form a non-homogeneous equation in x- and y-direction respectively. The solutions to these equations are presented in this work.

Volume Subject Area:
Fluids Engineering
Topics:
Buoyancy, Nanofluids, Transport phenomena, Nanoparticles, Fluids, Collisions (Physics), Flow (Dynamics), Particulate matter, Temperature
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