Daniel J. Lacks and R. Mohan Sankaran Case Western Reserve University
This International Research Experiences for Students (IRES) program will provide an international research experience at the Lanzhou University in China for four students from the United States each year. The intellectual merit of the work is to advance the scientific understanding of electrostatic charging in granular systems, both generally and specifically for the case of wind-blown dust. Electrostatic charging of granular systems is ubiquitous and has important consequences in both industrial and natural processes, but is very poorly understood. The impressive facilities at Lanzhou University, which include a wind-tunnel and a desert research station, offer a unique opportunity to carry out studies in a controlled but realistic environment and increase our understanding of particle charging in wind-blown systems. The broader impact of the program is to train US students in research with a global perspective; China is an ideal location for such a program, as the country has become a worldwide leader in industry, commerce and scientific research.
The specific goals of the study will be to carry out measurements of particle fluxes, particle size distributions, and particle charge distributions as a function of elevation in wind-blown dust systems. We will also measure electric fields as a function of elevation which will allow us to compare with previous studies, and correlate with particle flux, size and charging On one hand, we aim to understand how these electrostatic effects vary with parameters such as wind speed, overall particle size distribution, and humidity, and on the other hand how the electrostatic effects arise in natural conditions and what their consequences may be on dust migration. Our strategy will be to: (a) develop and validate methodology in laboratory scale experiments; (b) carry out well-controlled large scale wind tunnel experiments, where wind speed and direction, as well as other relevant parameters (e.g., particle size distribution, humidity), can be controlled; and (c) carry out field experiments in the desert, where the conditions (wind speed and direction, humidity, etc.) are not controlled and will vary significantly during the course of the experimentation, but where the results are most meaningful in regard to environmental and climatic implications. Students will work in interdisciplinary teams, serving in different roles throughout the project from designing experiments to carrying out field studies, and analyzing data.
