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

Title: Goldstar 2016 Interim Report: Brief Introduction to Urban Dispersion

Technical Report ·
DOI:https://doi.org/10.2172/1409943· OSTI ID:1409943
 [1]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). National Atmospheric Release Advisory Center (NARAC)

This section describes ways in which an urban environment can affect the distribution of airborne radiological material. In an urban area, winds at street level are significantly more variable and complex than the prevailing winds above the buildings. Elevated winds may be uniform and representative of the general flow over the surrounding area, but buildings influence the local flow such that the winds below the building heights vary significantly in location and time (Hanna et al 2006). For a release of material near an individual building, the complex effect of the building on the airflow may locally enhance the air concentration of released material in some regions near the building and reduce it in others compared to a release in open terrain. However, the overall effect of an individual building is to induce a rapid enlargement and dilution of an incident plume from an isolated source upwind of the building (Hosker 1984). A plume spreading through an urban environment of multiple buildings will experience enhanced mixing and greater spreading of the contaminant plume in both the vertical and horizontal directions, compared to the same release in open terrain.

Research Organization:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Organization:
USDOE
DOE Contract Number:
AC52-07NA27344
OSTI ID:
1409943
Report Number(s):
LLNL-TR-730798
Country of Publication:
United States
Language:
English