Calculation method for gamma dose rates from Gaussian puffs
Thykier-Nielsen, S; Deme, S; Lang, E
54 ENVIRONMENTAL SCIENCES; 56 BIOLOGY AND MEDICINE, APPLIED STUDIES; ATMOSPHERIC CIRCULATION; FISSION PRODUCT RELEASE; GAMMA RADIATION; GAUSS FUNCTION; RADIATION DOSES; CONTAMINATION; MATHEMATICAL MODELS; METEOROLOGY; MULTI-PARAMETER ANALYSIS; PLUMES
The Lagrangian puff models are widely used for calculation of the dispersion of releases to the atmosphere. Basic output from such models is concentration of material in the air and on the ground. The most simple method for calculation of the gamma dose from the concentration of airborne activity is based on the semi-infinite cloud model. This method is however only applicable for puffs with large dispersion parameters, i.e. for receptors far away from the release point. The exact calculation of the cloud dose using volume integral requires large computer time usually exceeding what is available for real time calculations. The volume integral for gamma doses could be approximated by using the semi-infinite cloud model combined with correction factors. This type of calculation procedure is very fast, but usually the accuracy is poor because only a few of the relevant parameters are considered. A multi-parameter method for calculation of gamma doses is described here. This method uses precalculated values of the gamma dose rates as a function of E{sub {gamma}}, {sigma}{sub y}, the asymmetry factor - {sigma}{sub y}/{sigma}{sub z}, the height of puff center - H and the distance from puff center R{sub xy}. To accelerate the calculations the release energy, for each significant radionuclide in each energy group, has been calculated and tabulated. Based on the precalculated values and suitable interpolation procedure the calculation of gamma doses needs only short computing time and it is almost independent of the number of radionuclides considered. (au) 2 tabs., 15 ills., 12 refs.
Risoe National Lab., Roskilde (Denmark). Meteorology and Wind Energy
INIS; OSTI as DE96610601
Denmark
1995-06-01
English
Technical Report
Other Information: PBD: Jun 1995
Medium: ED; Size: 22 p.
https://doi.org/
ON: DE96610601; ISBN 87-550-2019-4
RISO-R-775(EN)
Other: ON: DE96610601; ISBN 87-550-2019-4; TRN: DK9500172007795
DKN; SCA: 540130; 560101; PA: AIX-27:007795; EDB-96:030198; NTS-96:010990; SN: 96001535312
2011-07-25
177168
https://www.osti.gov/etdeweb/servlets/purl/177168