Cut-away views of components used to control the gas pressure and two-phase flow velocity. Left panel: hollow gas expansion unit where particles enter and slow when they reach the top of the sedimentation chamber. Right panel: apparatus base with pressure-reducing filter composed of sintered metal plates of porosity coefficient α = 10⁻¹² m². The funnel insert holds a fine wire mesh that is used as a particle staging platform; low-pressure air streaming through the mesh fluidises the particles.