Ersin ÖzuğurluCurrent Research
Applied Mathematics: Vortex interactions in quasi-geostrophic flowI have been working with Dr. Jean N. Reinaud and Prof. David G. Dritschel at the University of St Andrews, St Andrews, Scotland ((http://www-vortex.mcs.st-and.ac.uk) .
Postdoctoral ResearchApplied Mathematics: Effect of magnetic field in the Czochralski growth of silicon crystals I demonstrated my excellent research abilities by applying an optimization technique for controlling transport phenomena in the Czochralski Silicon crystal growth process with MASTRAPP2d (Multizone Adaptive Scheme for Transport Phase-change Processes.) MASTRAPP2d utilizes a multi-zone adaptive grid-generation technique MAGG for discretizing the physical domain and a curvilinear finite volume ( CFV) technique for solving the governing equations. The MAGG algorithm distributes grid nodes adaptively in response to the development of the solution and according to the evolution of the problem domain. Further details on the numerical methodology of MASTRAPP2d are provided by Hui Zhang (http://me.eng.sunysb.edu/zhang/Zhang.htm) and Vish Prasad (http://me.eng.sunysb.edu/prasad/Prasad.htm)
My postdoctoral research focused on Czochralski growth of silicon crystals. The application of a magnetic field in a Czochralski crystal growing from an electrically conducting melt has become a well-known technique for improving the crystal quality. It has been experimentally established that a magnetic field can stabilize or even suppress the convection in the melt, which together improves the interface conditions thus reduces the growth striations. Moreover, the appropriate application of a magnetic field allows control of the oxygen concentration in silicon crystals.
Practical experience has shown that strong flow fields in the melted crystal can cause crystal irregularities. Flaws in the crystal can only be detected at the end of the crystal growth process. However the flow field is directly observable experimentally, and can be reliably determined computationally. This suggests that one way to improve crystal would be to control the vorticity.
This work was presented in the annual meeting of DARPA/AFOSR (Defense Advanced Research Project Agency / Air Force Office of Scientific Research) http://thermsa.eng.sunysb.edu Consortium for Crystal Growth Research in New York and is ready for the journal submission. By working as a member of DARPA/AFOSR CCGR, I have augmented my rigorous knowledge of theory with practical experience.
Graduate Research Applied Mathematics: Free-surface problems
In my dissertation, "Effect of variable surface tension on free-surface problems,"
I accomplished three main objectives: