Development and calibration of a portable artificial rainfall simulator for reproducible experiments on soil erosion

Authors: Md. Enayet Chowdhury, Mohammad Shariful Islam, Md. Safin Shahriar, Md. Azijul Islam, Tahsina Alam

Abstract


Rainfall intensity and distribution has a great effect on soil erosion. In this study, a portable perforated steel tray is developed and calibrated to simulate artificial rainfall which can be used for investigation of soil erosion under a certain rainfall.The simulator's performance was compared with available tray and drip-type simulators as well as the natural rainfall. This is a drip-type simulator with the capacity of producing storms of up to 188 mm/h within 10 minutes. The higher value of D 50 (4.18 mm) of the rainfall simulator than the value of D 50 (3.25 mm) of natural rainfall indicates greater drop size distribution. The relatively lower height of the simulator to achieve the terminal velocity of natural rainfall was partially compensated by the greater drop size distribution. Fixing the perforated steel tray 3.3 m above ground surface generate a drop velocity of 4.2 m/s.The drop size distribution (D 50) was estimated using Flour Pellet Method. Christiansen's Uniformity (CU) Coefficient (86.2998% and 86.3143% for separate two runs) was determined for evaluation of Spatial Variability. Based on parameters such as raindrop size distribution, rain accumulation rate, spatial variability of rainfall and drop velocity, the simulator performs satisfactorily.

Publication Details

Published On: June 2018
Publication: Journal of Modern Science and Technology (JMST)
Project: Design, Operation and Performance Evaluation of a Portable Perforated Steel Tray Rainfall Simulator