Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Simplified modeling of air-flow dynamics in SSD radon-mitigation systems for residences with gravel beds. Final report, Aug 89-Feb 91

Technical Report ·
OSTI ID:7236667
In an attempt to better understand the dynamics of subslab air flow, the report suggests that subslab air flow induced by a central suction point be treated as radial air flow through a porous bed contained between two impermeable disks. (NOTE: Many subslab depressurization systems, those now considered most effective for mitigating residences for radon, do not perform entirely satisfactorily, even when designed and installed by professionals). The report shows that subslab air flow is most likely to be turbulent under actual field situations in houses with subslab gravel beds, but remains laminar when soil is present under the slab. The physical significance of a model is discussed, and simplified closed-form equations are derived to predict pressure and flows at various distances from a single central depressurization point. A laboratory apparatus was built to verify the model and experimentally determine the model coefficients of the pressure drop vs. flow for commonly encountered subslab gravel materials. These pressure drop coefficients can be used in connection with the simplified model as a rational way to assess subslab communication in houses. Preliminary field verification results in a house with gravel under the basement slab are presented and discussed.
Research Organization:
Princeton Univ., NJ (United States). Center for Energy and Environmental Studies
OSTI ID:
7236667
Report Number(s):
PB-92-195635/XAB; PU/CEES--246
Country of Publication:
United States
Language:
English