Numerical Simulation of Weakly Ionized Hypersonic Flow for Reentry Configurations

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76521/1/AIAA-2006-3773-970.pd

Development of an Unstructured Navier-Stokes Solver for Hypersonic Nonequilibrium Aerothermodynamics

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76685/1/AIAA-2005-5203-455.pd

Numerical Simulations of the FIRE-II Convective and Radiative Heating Rates

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76673/1/AIAA-2007-4044-617.pd

Hypersonic Aerothermodynamics Analysis Across Nonequilibrium Regimes Using Continuum and Particle Methods

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76877/1/AIAA-2007-3903-204.pd

Hybrid Particle-Continuum Simulations of Hypersonic Flow Over a Hollow-Cylinder-Flare Geometry

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77198/1/AIAA-36681-416.pd

High Performance Modeling of Atmospheric Re-Entry Vehicles

Re-entry vehicles designed for space exploration are usually equipped with thermal protection systems made of ablative material. In order to properly model and predict the aerothermal environment of the vehicle, it is imperative to account for the gases produced by ablation processes. In the case of charring ablators, where an inner resin is pyrolyzed at a relatively low temperature, the composition of the gas expelled into the boundary layer is complex and may lead to thermal chemical reactions that cannot be captured with simple flow chemistry models. In order to obtain better predictions, an appropriate gas flow chemistry model needs to be included in the CFD calculations. Using a recently developed chemistry model for ablating carbon-phenolic-in-air species, a CFD calculation of the Stardust re-entry at 71 km is presented. The code used for that purpose has been designed to take advantage of the nature of the problem and therefore remains very efficient when a high number of chemical species are involved. The CFD result demonstrates the need for such chemistry model when modeling the flow field around an ablative material. Modeling of the nonequilibrium radiation spectra is also presented, and compared to the experimental data obtained during Stardust re-entry by the Echelle instrument. The predicted emission from the CN lines compares quite well with the experimental results, demonstrating the validity of the current approach

Hybrid Particle-Continuum Simulations of Low Knudsen Number Hypersonic Flows

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76429/1/AIAA-2007-3892-932.pd

Re-entrant ferroelectricity in liquid crystals

The ferroelectric (Sm C$^*$) -- antiferroelectric (Sm C$^*_A$) -- reentrant ferroelectric (re Sm C$^*$) phase temperature sequence was observed for system with competing synclinic - anticlinic interactions. The basic properties of this system are as follows (1) the Sm C$^*$ phase is metastable in temperature range of the Sm C$^*_A$ stability (2) the double inversions of the helix handedness at Sm C$^*$ -- Sm C$^*_A$ and Sm C$^*_A$% -- re-Sm C$^*$ phase transitions were found (3) the threshold electric field that is necessary to induce synclinic ordering in the Sm C$^*_A$ phase decreases near both Sm C$^*_A$ -- Sm C$^*$ and Sm C$^*_A$ -- re-Sm C$^*$ phase boundaries, and it has maximum in the middle of the Sm C$^*_A$ stability region. All these properties are properly described by simple Landau model that accounts for nearest neighboring layer steric interactions and quadrupolar ordering only.Comment: 10 pages, 5 figures, submitted to PR

Chemically Reacting Plasma Jet Expansion Simulation for Application to Electrothermal Chemical Guns

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76610/1/AIAA-2007-4600-217.pd

Multiscale Particle-Continuum Simulations of Hypersonic Flow over a Planetary Probe

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76410/1/AIAA-37319-396.pd