Numerical wind speed simulation model

Abstract

A relatively simple stochastic model for simulating wind speed time series that can be used as an alternative to time series from representative locations is described in this report. The model incorporates systematic seasonal variation of the mean wind, its standard deviation, and the correlation speeds. It also incorporates systematic diurnal variation of the mean speed and standard deviation. To demonstrate the model capabilities, simulations were made using model parameters derived from data collected at the Hanford Meteorology Station, and results of analysis of simulated and actual data were compared. Generally, the major features found in the analysis of real data can be identified in the analysis of the simulated data. The frequencies of high hourly and daily average wind speeds are underestimated slightly by the model. However, the model is useful in its current state for examining the spatial correlation of winds at potential wind energy conversion sites, and for evaluating techniques for adjusting climatological statistics derived from limited observations.

Accident Simulation Study for Nuclear Power Plants Impacting Louisiana: Differences in 2017 vs. 1992 Protective Action Guidelines

“…This increased sensitivity results from the difference between the DCFs for an adult or child, respectively, for the various radioiodines. The thyroid DCF can be up to a factor of 2 higher for a 1-y-old child than it is for an adult (Ramsdell et al 2015). This is consistent with the results of this study, in which there are a large variety of accident conditions under which the extra child thyroid dose evacuation threshold added by LDEQ will result in an evacuation recommendation that would otherwise not occur.…”

“…This difference in inhalation dose is in turn driven by two main factors: The first is the difference in tissue weighting factor for the thyroid gland, which is 0.03 in ICRP 26 vs. 0.05 in ICRP 60, and the second is the more sophisticated Human Respiratory Tract Model (HRTM) introduced in ICRP 66 (ICRP 1994) that ultimately leads to differing inhalation Dose Coefficients (DC) in ICRP 72 (ICRP 1996). The Dose Conversion Factors (DCF) derived 14 from the DCs in ICRP 72 can be much higher than the 1992 DCFs for radionuclides other than iodine, but these potential particulates do not play much of a role in most accident scenarios (Ramsdell et al 2015). In general, most DCFs derived from the new DCs are similar, but the higher DCs of a few key isotopes such as 137 Cs can drive the final TED higher than the old TEDE would have been when large amounts of particulates are involved (Ramsdell et al 2015), as in the spent fuel scenario depicted in Figs.…”

“…The Dose Conversion Factors (DCF) derived 14 from the DCs in ICRP 72 can be much higher than the 1992 DCFs for radionuclides other than iodine, but these potential particulates do not play much of a role in most accident scenarios (Ramsdell et al 2015). In general, most DCFs derived from the new DCs are similar, but the higher DCs of a few key isotopes such as 137 Cs can drive the final TED higher than the old TEDE would have been when large amounts of particulates are involved (Ramsdell et al 2015), as in the spent fuel scenario depicted in Figs. 2 and 3.…”

“…For this reason, the EPA manuals list three rather than four sources of dose (US EPA 1992, 2017. The RASCAL software used in this study, however, uses a cloudshine model based on line sources and plane sources "until plumes and puffs grow to sufficient size to meet the assumptions associated with the semi-infinite cloud model" (Ramsdell et al 2012). Inhalation dose is based on the activity of the radionuclides in question calculated to have been deposited inside the body through inhalation, and so the total inhalation dose is integrated over 50 y for adults and 70 y for children.…”

Assessment of Source Terms and Potential Doses Due to Steam Generator Tube Rupture of VVER-1200 at the El Dabaa Nuclear Power Plant in Egypt

“…This study aims to examine the radiological consequences of a SGTR event with and without offsite power to identify the protective measures for safeguarding the public and the environment from radiological hazards. This analysis utilizes the Radiological Assessment System for Consequence Analysis (RASCAL) computer code [9] to focus on the radiological impact in the vicinity of the NPP unit at the El Dabaa site. The findings can inform the development of an evacuation policy and preparedness plan, facilitating the enactment of effective safeguards against internal and external environmental risks.…”