HR: 0800h
AN: H21B-1340 [Abstracts]
TI: On the Diffusivity of Water Vapor Under Thermal Gradients in Soils
AU: * Peschel, J M
EM: j-peschel@tamu.edu
AF: Texas A&M University, Department of Civil Engineering, College Station, TX 77843-3136
United States
AU: Cahill, A T
EM: tcahill@civil.tamu.edu
AF: Texas A&M University, Department of Civil Engineering, College Station, TX 77843-3136
United States
AB:
The isothermal transport of liquid water and water vapor in soils has been well understood for some time. Conversely, the
thermally-driven transport of these two components is less well characterized, and depends on a number of unobserved
hypothesized transport mechanisms. In field soils, the combination of the four components of isothermal liquid and vapor and
thermal liquid and vapor into one measured flux makes it difficult to isolate the magnitude and direction of any individual
component flux. An experimental system was designed to isolate and measure only the water profile in nonisothermal soils
caused by vapor transport. The thermal gradient was kept large so that the vapor transport would be dominated by the
thermally-driven flow instead of the isothermal vapor flow. Moisture content profile measurements over the temperature range
of 20oC to 70oC were taken. A basic framework of explanation for the findings is presented.
DE: 1866 Soil moisture
SC: Hydrology [H]
MN: Fall Meeting 2005