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Title: Buoyant plume calculations

Smoke from raging fires produced in the aftermath of a major nuclear exchange has been predicted to cause large decreases in surface temperatures. However, the extent of the decrease and even the sign of the temperature change, depend on how the smoke is distributed with altitude. We present a model capable of evaluating the initial distribution of lofted smoke above a massive fire. Calculations are shown for a two-dimensional slab version of the model and a full three-dimensional version. The model has been evaluated by simulating smoke heights for the Hamburg firestorm of 1943 and a smaller scale oil fire which occurred in Long Beach in 1958. Our plume heights for these fires are compared to those predicted by the classical Morton-Taylor-Turner theory for weakly buoyant plumes. We consider the effect of the added buoyancy caused by condensation of water-laden ground level air being carried to high altitude with the convection column as well as the effects of background wind on the calculated smoke plume heights for several fire intensities. We find that the rise height of the plume depends on the assumed background atmospheric conditions as well as the fire intensity. Little smoke is injected into the stratosphere unlessmore » the fire is unusually intense, or atmospheric conditions are more unstable than we have assumed. For intense fires significant amounts of water vapor are condensed raising the possibility of early scavenging of smoke particles by precipitation. 26 references, 11 figures.« less
Authors:
; ;
Publication Date:
OSTI Identifier:
6139588
Report Number(s):
UCRL-90915; CONF-850136-5
ON: DE85007255
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Conference
Resource Relation:
Conference: 23. AIAA aerospace sciences meeting, Reno, NV, USA, 14 Jan 1985
Research Org:
Lawrence Livermore National Lab., CA (USA)
Country of Publication:
United States
Language:
English
Subject:
45 MILITARY TECHNOLOGY, WEAPONRY, AND NATIONAL DEFENSE; 54 ENVIRONMENTAL SCIENCES; NUCLEAR EXPLOSIONS; ENVIRONMENTAL IMPACTS; PLUMES; DIFFUSION; CLIMATES; FIRES; HUMIDITY; MATHEMATICAL MODELS; SMOKES; WIND; AEROSOLS; COLLOIDS; DISPERSIONS; EXPLOSIONS; RESIDUES; SOLS 450202* -- Explosions & Explosives-- Nuclear-- Weaponry-- (-1989); 500300 -- Environment, Atmospheric-- Radioactive Materials Monitoring & Transport-- (-1989)