U.S.-France Cooperative Research: Flows of Grains Down Inclined Channels

这个为期三年的美法粒子科学合作奖涉及康奈尔大学和雷恩大学的研究人员和学生。美国的Michel Louge和法国的Luc Oger领导了这个关于颗粒沿倾斜表面重力流动的合作项目。他们将研究平坦摩擦平面上非线性颗粒波的起源和增长。这些波动可能会导致水流的间歇性堵塞。在康奈尔大学收集的实验数据将使用相应的水力理论的稳定性分析进行解释。这与法国在非线性稳定性和“细胞内质点”数值分析方面的专业知识相辅相成。第二个目标是确定在凹凸不平的斜坡上发生颗粒流碰撞的程度。如果它们能够持续，它们需要相对较小的倾斜角。为了研究它们的动力学，研究人员将利用雷恩的颗粒状设施降落伞，并根据他们的碰撞理论解释测量结果。这一奖项代表了美国方面对NSF和CNRS的平行提议。NSF将支付这名美国调查员和他的学生的旅费和生活费。CNRS将支持法国研究人员和学生访问美国。该项目探索粒子科学中的基本问题，这些问题对各种工业过程都有影响，从矿石的提取和加工，到化学工程，以及岩崩和雪崩等地质现象。

0233212LougeThis three-year award for US-France collaboration in particle science involves researchers and students at Cornell University and the University of Rennes. Michel Louge in the US and Luc Oger in France lead this cooperative project on the gravitational flow of grains down inclined surfaces. They will investigate the origin and growth of nonlinear granular waves on a flat frictional plane. These waves can lead to intermittent jamming of the flow. Experimental data collected at Cornell will be interpreted using a stability analysis of the corresponding hydraulic theory. This is complemented by French expertise in nonlinear stability and "particle-In-Cell" numerical analysis. The second goal is to establish how fully collisional granular flows can arise on a bumpy incline. If they can be sustained, they require relatively small angles of inclination. To study their dynamics, the investigators will utilize a granular facility chute at Rennes and interpret measurements based on their collisional theories. This award represents the US side of parallel proposals to the NSF and the CNRS. NSF will cover travel funds and living expenses for the US investigator and his students. The CNRS will support visits by French researchers and students to the United States. The project explores fundamental questions in particle science that have implications for industrial processes as diverse as the extraction and processing of ores and chemical engineering and geological phenomena like rockslides and avalanches.