Alexandria Engineering Journal (Dec 2018)
Controlling boundary layer separation in stretching sheet flow
Abstract
The effects of non-uniform nanoparticle concentration within the boundary layer flow due to stretching surface are analyzed by employing a non-homogeneous model of nanofluid which passively controls the concentration of nanoparticles at the surface. All fluid properties are simulated as function of nanoparticle concentration. For such a consideration a self-similar solution exists and its worth mentioning influence is to control the boundary layer separation which is subsequently found to depend upon diffusion parameter and nanoparticle concentration. Furthermore the results show that the behavior of nanoparticles distribution across the boundary layer is highly dependent upon variation of different parameters. For instance, Shmidt number leads to decrease the concentration layer thickness and nanoparticle concentration at the sheet but hydrodynamic and thermal boundary layers remained unaffected. The heat transfer and drag coefficient enhancement are also directly affected by the non-uniform behavior of nanoparticle is also an important observation towards the understanding of role of nanoparticle in momentum and thermal transport. Keywords: Moving sheet, Nanofluid, Heat transfer, Non-homogeneous modeling, Flow separation