Research Projects

The motion of objects on the surface of particulate media or within their bulk occurs frequently in nature and human activities, such as animals or vehicles moving on sand, earth-moving and excavation, sediment dredging from river or lake beds, and even rovers sent on missions to explore the surfaces of planets and asteroids. Despite their prevalence and importance, a fundamental understanding of the motion of objects through particulate media is still rudimentary, because robust physical and mathematical descriptions of the flow of particulate media are still in a stage of development. Nevertheless, some recent advances in continuum theories show promise, and the continuous improvements in computational power has made particle-based numerical simulations a powerful tool to study granular flow. This proposal aims to further the development of continuum models and boundary conditions for granular flow around flexible solid objects. The models will be used to develop scientific design principles that govern the motion of rigid and deformable objects in dry of fluid-submerged particulate media. The principles will be leveraged to design vehicles for locomotion in or on particulate media and earth-moving and shaping machines, which will have applications in industry, agriculture and defence. A key thrust is to engineer compliance of the solid surface to effect optimal performance, as done efficiently by living organisms. The theories and design principles will be tested extensively against particle simulations and experiments.