Published: Aug. 23, 2023

Nathalie VriendAssociate Professor Nathalie Vriend of the Paul M. Rady Department of Mechanical Engineering has been named a 2023 Experimental Physics Investigator by the Gordon and Betty Moore Foundation

The Moore Foundation’s Experimental Physics Investigators Initiative supports experimental physicists who may lack flexible research funding to tackle their most creative research ideas. Vriend will receive $1.25 million from the foundation over five years to further her innovative research in granular flows in the natural environment. 

Vriend’s research addresses a major gap in the understanding of the precise role of
the discrete particle phase in dense suspensions – particle-fluid mixtures where the particles are separated by less than a particle diameter.

Even though liquid-solid processes are ubiquitous and can be measured and modelled on a system scale, the scientific community is completely in the dark on the details and the implications of the particle phase. Vriend’s methodology presents a unique opportunity to characterize dense suspensions by quantitatively measuring and visualizing network interactions due to solid contact forces with unprecedented spatial and temporal resolution.

To accomplish this, Vriend will create dense particle-fluid mixtures using bespoke macroscopic photoelastic particles mixed in with fluids of different viscositiesdensities and temperatures.

Photoelastic particles visually show solid contact forces (both normal and shear). The team will combine this information with Particle Image Velocimetry (PIV) and Particle Tracking Velocimetry (PTV), directly resolving forces on particles and the fluid motion.

Vriend’s work on understanding the role that the particle-phase plays in suspensions has the potential to advance the analysis, modelling, predicting and forward-projecting of environment suspensions in natural hazards (e.g., landslides, avalanches), such as solid crystal mush mixed in with viscous magma deep in our Earth, ice crystals initiating in cold polar water reservoirs or sticky clay particles avalanching down the salty sea bottom in a turbidity current.