Technical Memorandum Report No. 78
Two-Dimensional Infiltration Equations: Soil-Box Laboratory Experiments
Shan-hsin Chiang and Yu-Si Fok
August 1985
ABSTRACT
Infiltration equations can be used to describe furrow and drip irrigation, groundwater recharge, and wastewater injection. Physical two-dimensional (2-D) infiltration equations for drip irrigation expressed in explicit, power algebraic forms were developed based on four consecutive time intervals which were derived in a previous study. Two-dimensional infiltration is assumed to be a composite of 2-D upward infiltration and downward infiltration components. These components of infiltration are computed on the assumption that the loci of the wetting pattern for 2-D infiltration are semiellipses. Because the developed equations are presented in explicit algebraic power forms, the physical parameters of the soil media, such as hydraulic conductivity, capillary potential, pressure head, soil porosity, and moisture content, can be expressed as dependent parameters of drip irrigation. The validity of the developed equations was examined in five laboratory experiments at different moisture contents. The results of coated infiltration show good agreement.