Exploration of rotating flows over a stationary plane surface by considering variable fluid properties

Abstract

Rotating flow occurring over a stationary or a rotating disk has immense theoretical and practical significance. Such flows are vital in different applications including aerodynamics where these are involved in the design of rotating machineries such as turbines, propellers and compressors. Rotating flows are also met in chemical and food processing industries, in electrochemistry and in the flow between a rotor and stator. Motivated by such applications, the thesis aims at discussing two different interesting types of rotating flow problems namely: (i) the Bödewadt flow around a stretchable surface and (ii) the boundary layer flow beneath generalized vortex, where the tangential velocity at the far field follows a power law form i.e. 𝑢థ ~𝑟௠ where 𝑟 is the radial coordinate and 𝑚 shows the power law index. Two distinct viscosity-temperature relations are applied to analyse solid flow configurations. However, an exponential viscosity-temperature correlation, established on an empirical result, is the main emphasis of present thesis. A set of transformations is employed to convert the Navier-stokes equations into boundary value problems comprising ordinary differential equations. An easy to apply yet reliable package bvp4c MATLAB is used to obtain computational results for wide range of Prandtl number. Graphical illustrations are obtained to enlighten the behavior of variable fluid properties on the considered flow situations. In case of variable fluid properties, computational data for the viscous drag exhibited at the surface of disk and the rate of heat transfer are substantially different from those found for the case of constant fluid properties. Present numerical findings are in perfect agreement with that of a previous study conducted with constant physical properties.