Astrophysical flow instabilities and turbulence
Interdisciplinary studies of dust-drag fluid instabilities in protoplanetary discs
In the cotext of dust-infused turbulent proto-planetary discs, fluid instabilities are considered a critical mechanism that cause accretion and help to form planetary precursors, known as planetesimals. The formation of planetesimals cannot be directly observed in protoplanetary discs, and so this topic relies upon expertise in theoretical and experimental flow dynamics.
Theoretical predictions
Simulation of a flow instability that is driven by the collective aerodynamic drag of dust particles in a dilute fluid. From (Lambrechts et al., 2016).
The way that solids bind together at different length scales in protoplanetary discs is hypothesized to be controlled by hydrodynamic instabilities arising from particle-drag dynamics. Simiplified simulations were run to isolate the mechanism of the aerodynamic particle clustering and to make predictions that could be tested experimentally.
Experimental findings
The dilute gas-dust stream facility In Göttingen. From (Capelo et al., 2019)
Experiments in a system with properties equivalent to the simulation parameters revealed a spontaneous clustering dynamic and collective particle drag reduction effects, that are characteristic of the predicted particle-drag induced fluid instabilities.
This work was conducted in collaboration with The Max Planck Institute for Dynamics and Self-organization, Germany, Lund University, Sweden, and the Technical University of Braunschweig, Germany.