Explicit equations for infiltration

Understanding infiltration processes is one of the fundamental points in the theory of drainage and irrigation engineering. The infiltration phenomenon has two limiting behaviors given by the two-parameter Green–Ampt and Talsma–Parlange equations. Both equations are unified to form a general three-parameter formula. The third parameter interpolates between these two limiting cases. This investigation attempts to find an explicit form of the generalized equation. The explicit equation is accurate, simple and easy to use in practical situations.