  We built and characterised a macroscopic self-assembly reactor that agitates
magnetic, centimeter-sized particles with a turbulent water flow. By scaling up
the self-assembly processes to the centimeter-scale, the characteristic time
constant scale also drastically increases. This makes the system a physical
simulator of microscopic self-assembly, where the interaction of inserted
particles are easily observable. Trajectory analysis of single particles
reveals their velocity to be a Maxwell-Boltzmann distribution and it shows that
their average squared displacement over time can be modelled by a confined
random walk model, demonstrating a high level of similarity to Brownian motion.
The interaction of two particles has been modelled and verified experimentally
by observing the distance between two particles over time. The disturbing
energy (analogue to temperature) that was obtained experimentally increases
with sphere size, and differs by an order of magnitude between single-sphere
and two-sphere systems (approximately 80 $\mathrm{\mu J}$ versus 6.5
$\mathrm{\mu J}$, respectively).
