Preliminary Numerical Simulation of IR Structure Development in a Hypothetical Uranium Release.
Abstract
We present a three-dimensional (3D) simulation of a daytime hypothetical uranium release at 200 km altitude. Of interest is the LWIR emission from uranium oxide ions, induced by sunlight and earthshine. Assuming a one-level fluid and integrated Pedersen conductivity ratio (cloud to ambient) of 5, the cloud diffuses along the magnetic field in time and rapidly develops gradient drift striations transverse to the magnetic field and across the direction of the relative velocity of neutrals to ions. Using the PHARO code, we produce contour plots of radiance in the 11-14 micron region to simulate observations from various locations both along and transverse to the magnetic field. Contours of radiance vary in intensity and character from different vantage points. Power spectra are calculated to quantify the development of spatial irregularities in the radiance. We find parallax to be an important effect which alters both the appearance of the radiance contours and the spectral characteristics. This inherently 3D effect could not be observed in previous 2D simulations. Altering the distance from observer to cloud or changing slightly the direction of observation can produce drastic changes in the observations. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 16, 1981
- Accession Number
- ADA107600
Entities
People
- B. E. Mcdonald
- E. Hyman
- M. Mulbrandon
- Sidney L. Ossakow
Organizations
- United States Naval Research Laboratory