### Sensitivity Analysis for a Radio Frequency Atmospheric Pressure Plasma Discharge Simulation

*A Dissertation Presented for the Doctor of Philosophy in Computational Engineering, The
University of Tennessee at Chattanooga*

#### Kyle J. Lange, July 2009

Abstract:

A radio-frequency atmospheric plasma discharge is simulated in two dimensions using
a finite volume discretization. The governing equations are based on a fluid model
which consists of ten continuity equations for different particle species, the electron
energy equation,Poisson’s equation for the potential and the surface charge density
equation for surface charge at a dielectric. Flux boundary conditions are implemented
at the electrodes and the dielectric wall that separates the electrodes. Secondary
electron emission is accounted for using an empirical formula and data from the literature.
Discrete sensitivity analysis is applied to the governing equations using forward
mode direct differentiation and reverse mode adjoint to compute sensitivity derivatives.
The algorithm to compute the sensitivity derivatives differs from more traditional
algorithms due to the different numerical approaches used to accelerate convergence.
Sensitivity derivatives are then used to increase the peak electron density in the
discharge for a small case.