Review of Methods for Estimating the Decay Constant (k) of Horton’s Infiltration Model
Ajayi Asishana Stanley
Department of Agricultural Engineering
Ahmadu Bello University Zaria
ajayistan@gmail.com +2348039714411
ABSTRACT
Horton’s equation is one of the earliest and most popular empirical models for simulating infiltration. The aim of this paper is to review and recommend the best method for determining Horton’s decay constant from a number of methods in terms of its simplicity and accuracy. Six (6) infiltration tests was carried out and the average of the six tests was used for determining the steady state infiltration rate ic = 4cm/hr and initial infiltration rate io = 34cm/hr. Three methods were used to evaluate the decay constant k, Method I and III gave same result 0.8099 and the result of Method II is 0.8086.It is clear that there is no significant difference between the results, although they are supposed to be the same, the challenge with method II is the fact that it is very error prone. Method I is highly recommended above Method II and III because it is less disposed to error and simple to calculate.Key words: Decay constant, linear regression, infiltration capacity, Horton’s model