Abstract:
In this thesis, a nanofluid boundary layer that develops above a plane permeable surface is
analysed numerically. The focus of this thesis is twofold. Firstly, to investigate the generalized
vortex flow in a 𝐶𝑢 โ 𝐴𝑙2𝑂3/water-based hybrid nanofluid subjected to viscous dissipation
effects using Tiwari and Das model. Secondly, to examine a two-phase Buongiorno
mathematical model for a generalized vortex flow. In present work, vortex motion is
characterized by a prescribed tangential flow with velocity proportional to 𝑟𝑚, where 𝑟 is radial
coordinate and 𝑚 denotes the power-law index. Simulations are made by assuming a powerlaw
surface temperature distribution. Different from previously adopted practice, the diffusion
coefficients are not assumed constant here. A similarity solution is proposed, which transforms
the constitutive equations into a coupled differential system whose solution is evaluated
numerically by MATLAB function bvp4c. Results display a considerable expansion in thermal
boundary layer whenever nanoparticles are present. Important quantities like normalized wall
shear, disk cooling rate and entrained flow are scrutinized for varying choices of parameters.
The contribution of Brownian diffusion and Soret effect on the vortex induced motion is
studied. The graphical and tabular results demonstrate that these parameters provide a
remarkable enhancement in the heat and mass transfer rate.
