Molecular mechanisms of gas surface interactions in hypersonic flow

COMP 342

Ioana Cozmuta, icozmuta@mail.arc.nasa.gov, Eloret Corporation, Space Technology Division, NASA Ames Research Center, Mail Stop 230-3, Moffett Field, CA 94035
The fundamental understanding of gas-surface interactions under hypersonic conditions (usually described by pressures in the range of [0.01-0.1] atm and temperatures between 1000K and 1900K) characteristics to entry of a spacecraft in a planetary atmosphere is currently of great interest. An accurate model of surface mediated interactions would provide proper boundary conditions for computational fluid dynamics codes and aid in reducing the uncertainties associated with the calculation of heat load. Molecular dynamics simulations (classical as well as reactive potentials) are employed to characterize, at the molecular level, the interactions between a quartz (SiO2) surface and atomic oxygen and nitrogen. The present study – a first of its kind in understanding surface catalicity –provides relevant information on collision statistics, gas phase chemistry as well as surface mediated adsorption, diffusion and recombination reactions, relevant to the design of thermal protection systems.
 

Poster Session
6:00 PM-8:00 PM, Tuesday, August 21, 2007 BCEC -- Ballroom Foyer, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, August 20, 2007 BCEC -- Exhibit Hall - B2, Sci-Mix

Division of Computers in Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007