Study of infiltration process under different experimental conditions

In the present study, an attempt was made to evaluate the effect of head of ponding, diameter of ring infiltrometer and depth of penetration on cumulative infiltration. The effectiveness of a double ring infiltrometer on reducing lateral flow was also studied. The observations on cumulative infiltration were taken for different cases, viz., (i) single ring infiltrometers of 0.1, 0.15, 0.2, 0.25 and 0.3 m diameters and 0.06, 0.13, 0.16, 0.2, 0.26 m head of ponding with 0.07 m depth of penetration, (ii) 0.1 m diameter single ring infiltrometer with 0.3 m depth of penetration and (iii) double ring infiltrometers with 0.1–0.35 and 0.35–0.6 m set combination with 0.07 m depth of penetration. The study was conducted in G1 block of Crop Research Centre, G.B. Pant University of Agriculture and Technology, Pant Nagar, India. The infiltration data obtained for different combinations were used to study the effect of the parameters on wetting front advance and observed that the length of wetting zone at the central axis of the infiltrometer increases with increasing diameter of infiltrometer and head of ponding. Vertical and lateral components of cumulative infiltration were estimated from the moisture stored in the soil during the infiltration process. The lateral component ranged from 31.8 to 67.9% for the case of single ring infiltrometers and 11.7–11.92% for the case of double ring infiltrometer with 0.07 m depth of penetration. It shows that the lateral component of infiltration is reduced by three to six times with double ring infiltrometer. The excess amount of lateral component estimated with single or double ring infiltrometer is to be taken into account while designing an irrigation system. Further, a dimensionless equation was developed to predict the cumulative infiltration and the results are found very close to the observed data.