skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Sensitivity and uncertainty studies of the CRAC2 code for selected meteorological models and parameters. [CRAC2]

Conference ·
OSTI ID:5977584

We have studied the sensitivity of results from the CRAC2 computer code, which predicts health impacts from a reactor-accident scenario, to uncertainties in selected meteorological models and parameters. The sources of uncertainty examined include the models for plume rise and wet deposition and the meteorological bin-sampling procedure. An alternative plume-rise model usually had little effect on predicted health impacts. In an alternative wet-deposition model, the scavenging rate depends only on storm type, rather than on rainfall rate and atmospheric stability class as in the CRAC2 model. Use of the alternative wet-deposition model in meteorological bin-sampling runs decreased predicted mean early injuries by as much as a factor of 2-3 and, for large release heights and sensible heat rates, decreased mean early fatalities by nearly an order of magnitude. The bin-sampling procedure in CRAC2 was expanded by dividing each rain bin into four bins that depend on rainfall rate. Use of the modified bin structure in conjunction with the CRAC2 wet-deposition model changed all predicted health impacts by less than a factor of 2. 9 references.

Research Organization:
Oak Ridge National Lab., TN (USA); National Oceanic and Atmospheric Administration, Oak Ridge, TN (USA). Atmospheric Turbulence and Diffusion Lab.
DOE Contract Number:
AC05-84OR21400
OSTI ID:
5977584
Report Number(s):
CONF-850206-25-Summ.; ON: TI85007573
Resource Relation:
Conference: International ANS/ENS topical meeting on probabilistic safety methods and applications, San Francisco, CA, USA, 24 Feb 1985
Country of Publication:
United States
Language:
English