Accession Number : ADA505555


Title :   A High-Order Transport Scheme for Collisional-Radiative and Nonequilibrium Plasma


Descriptive Note : Doctoral thesis


Corporate Author : OHIO STATE UNIV COLUMBUS DEPT OF MECHANICAL ENGINEERING


Personal Author(s) : Kapper, Michael G


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a505555.pdf


Report Date : 06 Feb 2009


Pagination or Media Count : 214


Abstract : A series of shock tube experiments performed in the 1970s at the Institute for Aerospace Studies, University of Toronto, led in the discovery of instabilities in relaxing shock structures in noble gases under hypervelocity conditions. The instabilities were oscillatory in nature and found to affect the entire shock structure including the translational front, induction zone, and electron avalanche. Theoretical models were first developed in order to reproduce the length and time scales of the observed quasi-equilibrium state, and later extended to include unsteady plasma-dynamic simulations that verified the influence of pressure oscillations in one dimension. Despite these attempts, a complete explanation for the oscillations nor a quantitative analysis of the multi-dimensional shock structure has been provided to date. This dissertation builds upon previous modeling efforts, extending the numerical simulations to a high level of accuracy and detail so that coupling of complex wave phenomena and nonequilibrium effects can be well resolved. This has necessitated the development of a numerical capability aimed at relaxing shock layers and other unsteady, high-enthalpy nonequilibrium plasmas and is the focus of much of this work. The plasma is described as a two-temperature, single fluid with the electronic states convected as separate species. Solution of the convective transport is handled via upwind shock-capturing techniques, extended to third-order on general curvilinear meshes.


Descriptors :   *NONEQUILIBRIUM FLOW , *PLASMAS(PHYSICS) , *TRANSPORT , *RADIATIVE TRANSFER , *SHOCK TUBES , NUMERICAL ANALYSIS , ACCURACY , THESES , CONVECTION , MESH , TIME , AEROSPACE SYSTEMS , ELECTRONIC STATES , SCALE , SHOCK , FLUIDS , SHOCK TESTS , OSCILLATION , HYPERSONIC VELOCITY , ENTHALPY , MULTIPURPOSE , WAVES , INDUCTION SYSTEMS , PLASMA DIAGNOSTICS , RANK ORDER STATISTICS , MAGNETOHYDRODYNAMICS , VARIABLE PRESSURE , CURVES(GEOMETRY) , RARE GASES , FLUX DENSITY , AVALANCHE EFFECT(ELECTRONICS) , PLASMA WAVES , RAYLEIGH TAYLOR INSTABILITY , STRUCTURES , LAYERS , QUANTITATIVE ANALYSIS , PHOTORECOMBINATION LASERS , MATHEMATICAL MODELS , LINEAR SYSTEMS


Subject Categories : Plasma Physics and Magnetohydrodynamics


Distribution Statement : APPROVED FOR PUBLIC RELEASE