Constitutive relations for granular flows

Particulate flows are found in a range of situations, both in nature and industry. Many processes in the pharmaceutical, foodstuff and chemical industries rely on particulates, since they are easier and cheaper to transport and store than many liquid based products. Due to this widespread use, there is alot of interest in understanding how to make these particlulate systems flow in a controlled fashion, so as to maintain product quality and minimise the energy used to move them. Models of these systems are generally based on ideas similar to those employed for liquids and gases, but it has been discovered that although these theories do a reasonable job, they are missing some key properties of particulate flows. In this project we will determine and validate the key constitutive properties of a granular flow, and enabling us to isolate the parameters that control particulate flow behavioiur for the first time.