Steve Southern's Individual Contribution Page

Fall 2009 Mid-Semester Contributions

This semester was spent doing flocculator simulation work in an attempt to model the flow far from the inlet where conditions become steady. The goal was to obtain a full flow description so the performance of a particular flocculator geometry could be understood. I worked on two different methods to achieve this result. A large amount of time was spent trying to implement a periodic boundary condition case which has the specific purpose of modeling fully developed phenomena far from inlet effects. I worked to create a geometry and mesh that were compatible with the requirements FLUENT puts on its periodic solver and to set up the physics and solution methods such that a converged solution could be obtained. The second approach involved increasing the number of baffles to a number never tried before and letting the computer take its time to solve a mesh containing ~10^5 cells. The first method can now essentially be discarded as not worthwhile. Despite the simplicity of the model (fewer cells, fewer required boundary conditions), there was no solution to this case because variables had to be streamwise periodic. The many-baffle set up seems far more promising. It only takes about ten baffles to get the sort of flow consistency that we were looking for with the periodic case. I was able to examine these results and for the last few baffles, the pressure drops become constant and energy dissipation rates are uniform at a specified y point across each turn. I also wrote a simple MATLAB code that converts old Gambit journal files for geometry and meshing to the new workbench format so that work done in previous years can be easily modified and serve as a foundation for future simulations.