Enhancing Experimental Reliability Through Rainfall Simulator Calibration Under Intense Rainfall Rates

Acknowledging the benefit of Rainfall Simulators (RS) is continuously growing among researcher, mainly for laboratory-scale models where natural rainfall is either unavailable or inconsistent. RS put forward a reliable platform for replicating specific rainfall events under standardized set-up, making them invaluable for erosion, hydrology, and slope stability research needs. The present work offered a cost-effective Dripping Rainfall Simulator (DRS) for application on a 1.2 m² test plot area. After several standardizations, the DRS that produces replicable storms of rainfall (at 60 mm/hr and 120 mm/hr) demonstrated satisfactory spatial uniformity, with Christiansen’s uniformity coefficients (CUC) coverage ranging from 81.18–88.69% distribution across the monitoring plot. Additionally, the mean diameters (Dm ) and median volumetric drop diameters (D50), measured using a flour-pellet method, were found to extend from 3.8–4.4 mm and 2.7–3.1 mm independently which line up well with values reported in previous research. The relative terminal velocity (VT ) calculated was attained to range between 8.59–8.92 m/s with energy flux from 36.88 to 39.77 J/mm/m2 . These findings verify the RS capability to replicate natural rainfall with considerable accuracy let alone provide a strong foundation to be used in future applications in experimental modelling. From the basis of this study regarding RS, researchers will be able to create events-scale physical models in their relevant engineering areas.