Capillary barrier system development for water conservation in arid lands: Ⅱ. Determination of coupled heat and moisture diffusivity parameters

摘要

In part one of this investigation (Mohamed and Shooshpasha, 2002), a capillary barrier system was designed and tested for arid land environment. In this part, diffusivity parameters involved in the coupled heat and moisture flow equations were evaluated. The multilayer soil-based capillary barrier was subjected to both thermal and hydraulic fluxes in opposite directions. The parameters were determined via the use of experimental data and a nonlinear optimization technique. The calculated parameters are presented and discussed. Good agreement between calibrated values and experimentally determined volumetric moisture content implies that the diffusivity parameters could be represented by a linear function of the volumetric moisture content and temperature.