Numerical simulation and optimization of nanofluids in a complex micro heat sink

In this study, numerical simulations by single-phase and two-phase models of Al2O3/water nanofluids forced convection in a three-dimensional complex micro heat sink with uniform constant heat flux are investigated. The results indicate that the averaged Nusselt number increases with the increase of the nanoparticle volume concentration and the Reynolds number and achieves a 29-39% enhancement by the two-phase model compared with the single-phase model. However, the maximum increase of the pressure drop is 4.68%. The multiparameter constrained optimization procedure integrating the design of experiments (DOE), response surface methodology (RSM), genetic algorithm (GA), and computational fluid dynamics (CFD) is proposed to design the geometric configuration for the complex micro heat sink. The numerical optimization indicates that the enhancement of thermal performance factor. can achieve 9-16% in the optimization compared with the original case.