ESR 11


Behaviour of dense granular systems: predicting flow regimes for bulk material handling

This project concentrates on studying micro-scale mechanisms in dense granular flows. It will investigate particle-scale behaviour to characterise the bulk mechanical responses under compression and shearing regimes. There are several deliverables in the present study and the main one is to develop a novel and improved continuum description through micro-scale observations and simulations. Successively, both numerical and experimental methods will be employed to inform new constitutive models. These constitutive models can be embedded in numerical codes to allow for efficient numerical modelling involving dense granular materials.

The development of continuum models at bulk-scale will deploy DEM (Discrete Element Method) to simulate the particle interaction and provide an insight into the overall response. I am currently simulating rectangular silos and investigate the flow behavior and velocity profiles of the particles in the presence of wall friction in the system. The effect of particle’s shape and size distribution will also be considered to include the effect of particle scale (micro-level) on overall discharging characteristics of the silo, such as flow regimes, shear banding and force chains.

At the end of the second year, the study will focus on employing experimental techniques, used for the determination of the deformation  mechanism, to characterize dense granular materials. Accordingly, the flow pattern and stress distribution in silos will be investigated in a centrifuge test device.

Simultaneously, non-invasive visualization techniques, such as Particle Image Velocimetry (PIV) or X-ray tomography (depending on the applicability in testing conditions) will be used to provide comprehensive and reliable results on flow regime in realistic loading conditions. Depending on the obtained results and needs of the project, model silos available at University of Edinburgh might also be used as experimental tools.

Consequently, the overall project will incorporate results from a numerical solution, which simulates particle interactions in a defined assembly under different external and internal forces, and also advanced experimental tools to provide a clear explanation on behaviour of dense granular solids.  


Behzad Soltanbeigi

Biography

Nationality: Iranian

Current stay: iPAT, TU Braunschweig, Braunschweig, Germany

Previous Stay: University of Edinburgh, Scotland, The United Kingdom

I started my undergraduate in 2007 at IAUT in Civil Engineering in north-west of Iran. There, I started to learn about the basic principles of my field and found out widespread applications of engineering issues in our life. After successfully passing all the theoretical and practical courses and defending my final year dissertation, I graduated at 2011. Then I decided to move to Turkey and continue my graduate study there. I entered into MSc studies with the golden opportunity of studying at Bogazici University in Istanbul. It was the time I realized my enthusiasm for researching in topics related to geotechnical engineering. My thesis investigations were focused on monitoring stiffness of granular soils under simple shear condition. Afterwards, I was involved as a researcher in a project on modeling cohesionless backfills behind a model retaining wall. There, I learned more about visualization techniques used for studying complex characteristics of granular media. However, my eagerness to pursue graduate studies took me a step forward and I got the admission to enter PhD level at University of Edinburgh under the framework of the T-MAPPP project in summer of 2014.

Contact details

Email: b.soltanbeigi@tu-braunschweig.de

Behzad Soltanbeigi