Premium
Estimation of Intrinsic Length Scales of Flow in Unsaturated Porous Media
Author(s) -
Assouline Shmuel,
Ciriello Valentina,
Tartakovsky Daniel M.
Publication year - 2017
Publication title -
water resources research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.863
H-Index - 217
eISSN - 1944-7973
pISSN - 0043-1397
DOI - 10.1002/2017wr021629
Subject(s) - hydraulic conductivity , porous medium , flow (mathematics) , hydraulic head , sensitivity (control systems) , capillary pressure , pressure head , scale (ratio) , head (geology) , capillary action , evaporation , function (biology) , drainage , mechanics , length scale , mathematics , materials science , geotechnical engineering , soil science , environmental science , porosity , geology , thermodynamics , physics , soil water , engineering , composite material , electronic engineering , ecology , biology , quantum mechanics , geomorphology , evolutionary biology
Abstract Characteristic lengths govern processes related to flow in unsaturated porous media, e.g., during drainage or evaporation. One can estimate these lengths, i.e., air‐entry pressure head and critical capillary head, from either a water retention curve (WRC) or a hydraulic conductivity function (HCF). We provide new analytical expressions for the characteristic lengths based on a linearized analysis of the WRC and HCF curves. These are then used to investigate the impact of model selection on length‐scale estimates, to assess their sensitivity to model parameters, and to provide guidelines for the choice of the alternative expressions under flow scenarios of interest.