SIMULATION OF LAMINAR CONVECTION FLOW OF AL2O3-WATER NANOFLUID IN AN ASYMMETRIC HEATED CHANNEL

The present paper proposes a two dimensional analysis of the laminar convection flow of water-Al2O3 nanofluid inside a rectangular section channel with non-symmetric boundary conditions. In particular, a constant heat flux is applied on the top surface of the channel and an adiabatic condition on the bottom one. This situation is typical of many devices, such as solar collector, which receives thermal radiation from the top surface with objective to heat a working fluid, water- Al2O3 in the present case, and which are insulated on the bottom one in order to limit energy waste. Numerical simulations are developed by using the commercial software COMSOL, which employs finite element methods approach to solve the conservation equations, moreover thermal dependent properties are considered in the simulations The analysis is conducted for Re numbers ranging between 500-1000, concentration between 0%-6% and dimension of particles between 20-60 nm. An increase of Nu is observed at the increase of the concentration, as well as a substantial increment of the pressure losses.