Comparison of the performance of traditional advection-dispersion equation and mobile-immo

Comparison of the performance of traditional advection-dispersion equation and mobile-immobile model for simulating solute transport in

heterogeneous soils

Haizhu HU; Xiaomin MAO

【期刊名称】《《农业科学与工程前沿：英文版》》 【年(卷),期】2016(000)003

【摘要】The traditional advection-dispersion equation(ADE) and the mobile-immobile model(MIM) are widely used to describe solute transport in heterogeneous porous media. However, the fitness of the two models is casedependent. In this paper, the transport of conservative,adsorbing and degradable solutes through a 1 m heterogeneous soil column under steady flow condition was simulated by ADE and MIM, and sensitivity analysis was conducted. Results show that MIM tends to prolong the breakthrough process and decrease peak concentration for all three solutes, and tailing and skewness are more pronounced with increasing dispersivity. Breakthrough curves of the adsorbing solute simulated by MIM are less sensitive to the retardation factor compared with the results simulated by ADE. The breakthrough curves of degradable solute obtained by MIM and ADE nearly overlap with a high degradation rate coefficient, indicating that MIM and ADE perform similarly for simulating degradable solute