A Controlled Rainfall Simulator
Abstract
This study presents the design, integration, and performance evaluation of a controlled rainfall simulator developed as an add-on for a landslide simulation system. The simulator generates rainfall intensities from 0 to 20 mm/h, adjustable via a web interface, and operates using six spraying cycles per hour. Each cycle employs ON/OFF control with volume-based feedback: the pump runs until the accumulated volume reaches the predefined target, then stops automatically. A Proportional–Integral (PI) controller maintains a stable flow rate of 2 L/min to ensure consistent spray performance. The device is fully integrated with the landslide simulator chamber, enabling controlled rainfall experiments on various slope configurations. Experimental results show that the system maintains rainfall intensity with a volume error below 5% across all tests. However, the distribution uniformity remains below 80%, indicating the need for nozzle configuration improvements for applications requiring higher homogeneity. Overall, the system enhances the capability of landslide simulation experiments and supports research in soil stability and hydrological processes.