Simulation of Rainfall Hyetograph Based on Cascades Tanks Routing

Since most of water and soil researches require artificial rainfall simulation, thus rainfall simulators are applied instruments in this field of study. For this reason, various rain simulators have been designed, built and employed in researches till now. Even though all rainfall simulators provide good simulation for rainfall intensity, but simulation of varied rainfall by them are expensive and complicated, and field study cannot conducted easily by them. Thus, in this research, in order to simulate rainfall similar to natural rain and applicable for field tests, it is aimed to design and build a simple and affordable rainfall simulator using flow cascades reservoirs (tanks) routing. The result of calibration the simulator shows it has error less than 5%. Moreover simulation of observed hyetograph of Niyavaran station showed error of 6.1%. The simulator can simulate hyetographs with 3 hours duration and 30 millimeter per hour intensity. Consequently, the proposed instrument and its numerical model can be applied for simulating artificial rainfall hyetograph in rainfall erosion and infiltration field research tests.