Physical Simulation of Infiltration Equations

A method of using laminar (capillary) flow models for synthesizing the infiltration process on physical hydrologic models is described. The equations defining laminar flow in capillary tubes and between parallel plates were derived for several different geometric configurations representing horizontal, vertically downward, vertically upward, an radial flow. The theoretical equations for the different configurations are shown to be analogous in functional form to the theoretical and empirical infiltration equations used to define the time variation in the infiltration rate of a soil. The results from several tests conducted on capillary tubes were in close agreement with those obtained from the theoretical equations. Thus it was concluded that capillary flow models can be used to synthesize the infiltration process on physical models.