Analysis and optimization of various sediment catchers in a portable wind tunnel for soil erosion research

To investigate the isokinetic and aerodynamic performance of aeolian sediment catchers a detailed set of experiments in a Portable Wind and Rainfall Simulator (PWRS) has been executed. Atmospheric flow as a major driver for soil erosion dictates a fundamental understanding of the aerodynamic properties of the used sediment catchers in wind tunnel experiments and in the field. In order to build a new functional trap meeting the requirements of the PWRS, the present work examined and evaluated a conceptual wedge shaped trap from Trier University, Modified Wilson and Cook (MWAC) samplers, and two self-built wedge shaped prototypes. Experiments were carried out at six wind velocities ranging from 6.8 – 13.8 m s-1 and measured with a hot wire anemometer probe. The results show that the two self-built prototypes are performing isokinetic and provide acceptable aerodynamic properties, whereas the conceptual trap from Trier University and the MWACS did not achieve an isokinetic status and provided weaker aerodynamic properties than the self-built prototypes. In conclusion, isokinetic and aerodynamic measurements are valuable methods to improve sediment catchers, in relation to the wind fields surrounding them. As each portable wind tunnel has specific characteristics, the sediment catchers should always first be examined for their basic capabilities in the wind tunnel used.