Mechanical Engineering Commons^™

Surface Topography Formation And Thermographic Analysis In Laser Polishing Of H13 Tool Steel, Joshua D. Miller

Electronic Thesis and Dissertation Repository

Laser polishing, in its simplest form, is the melting of a small layer of material via laser radiation. This creates a small molten pool which is re-distrusted across the surface, resulting in a much smoother finished surface. Although this process has been around for decades now, there has been a recent insurgence into industrial applications. Despite this, the phenomena that occur during the process are still not fully understood. Therefore, increasing the knowledge surrounding the process would be ideal.

To accomplish this, various input parameters of the process are altered to analyze the effect on the finished polished surface. Through …

The Development And Numerical Modelling Of A Representative Elemental Volume For Packed Sand, Ashraf Thabet

Electronic Thesis and Dissertation Repository

The motivation of this thesis is the development of simple microscopic-scale model (representative elemental volume; REV) that can be used to conduct flow and heat transfer simulations from which closure coefficients can be established for the volume-averaged transport equations for porous media (packed bed). The thesis provides a brief introduction to the computational technique adopted for the geometric generation of the REV (YADE), followed by a parametric study undertaken to reveal the minimum number of particles inside the REV that are required to mimic the appropriate physics. Additional analysis was conducted with the goal of determining the influence of deviation …