Numerical investigation of nanofluid flow and conjugated heat transfer in a micro-heat-exchanger using the lattice Boltzmann method

In this article, simulation of nanofluid flow and conjugated heat transfer in a micro-heat-exchanger is studied using the lattice Boltzmann method. Hot and cold streams enter the heat exchanger in opposite directions and heat transfer occurs between the two streams through a wall. The effect of nanoparticles volume fraction and diameter on the heat transfer and also the effect of viscous dissipation on the heat transfer performance are studied. Results show that increasing the nanoparticles volume fraction to phi = 5% causes 18% enhancement in the Nusselt number compared to the pure water. Also, increasing the nanoparticles diameter from 11 nm to 100 nm for phi = 5% results in 13.33% decrease in the Nusselt number. Finally, considering the viscous dissipation effect, reduction in the Nusselt number is observed.