Kirkuk University Journal for Agricultural Sciences (KUJAS)

Application of Artificial Rain Technology to Ensure Quality Rainfall Distribution in Duhok, Kurdistan-Iraq

https://doi.org/10.58928/ku26.17113
Volume 17, Issue 1
Winter 2026
Page 105-114
Kirkuk University Journal for Agricultural Sciences (KUJAS)

Document Type : Research Paper

Authors

Jiyar Hussein Ali 1
Abdulsattar Haji Sulaiman 2

1 1 Department of Soil and Water Sciences, College of Agricultural Engineering Sciences, University of Duhok, Duhok, Kurdistan Region, Iraq.

2 2Department of Soil and Water Sciences, College of Agriculture, Duhok University, Duhok, Iraq.

Abstract
The artificial rainfall technique (or rainfall simulation) uses a rainfall simulator device that sprays water over the soil surface in a controlled and systematic way to imitate real rainfall conditions in terms of drop size, intensity, terminal velocity and duration. The primary objective of this study is to systematically compare the outcomes obtained through specific performance indicators to evaluate the homogeneity and uniformity distribution of artificial rainfall. This assessment aims to establish artificial rainfall as a feasible and reliable alternative to natural rainfall, particularly in regions where natural precipitation is inconsistent or insufficient. By employing a rigorous experimental design and quantitative analysis, the study seeks to provide empirical evidence supporting the use of artificial rainfall simulations in environmental research and land management practices. The study was conducted on Duhok University Campus 7 km southwest of Duhok City-Iraqi Kurdistan region. Rainfall distribution was observed by 24 catch cans positioned uniformly inside the 12 plots. Christiansen coefficient and Wilcox–Swailes was used to statistically evaluate the performance of the artificial rainfall distributed by using drop size properties of artificial rain based on the available values of 2 mm diameter of sprinkler holes.The results showen that the mean of terminal velocity was 9.745m/s, and according to the rainfall intensity and kinetic energy was 27.925 J/m²·mm and 65.7 mm/h respectivly. The Christiansen Uniformity Coefficient (CU) and Wilcox–Swailes Uniformity Coefficient (U) showed excellent uniformity in artificial rain across the study area, with a high value of 99.04–99.22% respectively where most of the previous research results ranged between 80-90%.

Keywords

Artificial rainfall
kinetic energy
soil erosion
terminal velocity
uniformity coefficient
Subjects
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