The Evaporation and Gaseous Dispersion of Large-Scale Releases of Nitrogen Tetroxide
LAWRENCE LIVERMORE NATIONAL LAB CA
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A series of large-scale spills 3-5 cubic m of nitrogen tetroxide N204 was performed at the Nevada Test Site NTS for the Air Force Engineering and Services Laboratory, Environics Division. The purpose of these experiments was to study the evaporation rates and heavy gas dispersion aspects of realistic size releases of N204, a rocket fuel oxidizer for the Titan II missile system. The Titan II complexes are currently being decommissioned, resulting in an increase in the overland transportation of this toxic material. The normal boiling point for the liquid N204 is 21 deg C hence it evaporates rapidly when spilled onto warm soil and quickly dissociates into nitrogen dioxide N02 as it mixes with air. The N02 is highly toxic with an ACGIH threshold limit value 3 parts per million ppm. The design of the spill facility and the diagnostics are described. Some typical results for one of the spills are presented. The data include the atmospheric boundary layer conditions in effect during the spill, the spill area heat flux and vapor temperature, the vapor flux measured at 25 meters m downwind, and the N02 gas concentration contours at 785 m. A comparison of the measured N02 concentration and that calculated with the Air Force Ocean BreezeDry Gulch OBDG model is discussed.
- Safety Engineering
- Fluid Mechanics
- Liquid Rocket Propellants