Research Abstracts Online
January 2010 - March 2011
University of Minnesota Twin Cities
College of Science and Engineering
of Mechanical Engineering
PI: Joachim V. Heberlein, Associate Fellow
Plasma processing is increasingly being used to develop new materials processing technologies and improve existing ones. Process models may be used as design tools to simulate complex phenomena such as magneto-fluid-dynamic interactions, electric arc instability, plasma turbulence, and particle breakup and transport that take place in processes such as wire-arc spraying, plasma deposition, plasma cutting, and plasma spraying.
Thermal plasmas can be described by a set of fluid conservation and electromagnetic equations, complemented by suitable thermodynamic and transport properties, forming a strongly coupled non-linear system of transient-advective-diffusive-reactive equations. Computer codes for the accurate solution of these equations have been developed and are currently modified by this group. These codes are based on finite-element as well as finite-volume methods suitably designed to be accurate, robust, and flexible in order to be applied to different research projects. In addition, these researchers have begun exploring the viability of general-purpose CFD codes, such as FLUENT and OpenFOAM, for modeling of thermal plasmas. All of these projects involve the iterative or transient solution of very large sets of strongly coupled non-linear equations, often using very fine grids in two- or three-dimensional geometries, and therefore, require substantial computational resources. The group has started developing optimized, parallel versions of their codes with the help from MSI user support. The parallel versions of these codes will allow the researchers to explore physical processes (i.e. thermodynamic and chemical non-equilibrium effects, plasma-surface interactions, turbulence) which, due to their computational cost, are unfeasible to be modeled using single-processor systems.
David J. Osterhouse, Graduate Student
Venkat Raman Thenkarai Narayanan, Graduate Student