Lagrangian particle tracking measurements provide new insights into the onset of turbulence in pulsatile particle-laden pipe flow

Abstract

Particle suspensions in pulsatile pipe flow are ubiquitous in industrial processes and physiological systems. Of particular interest is the turbulence transition in such flows, where turbulent structures typically arise localized in time and space due to the pulsation. To elucidate the particle-flow interaction, we perform three-dimensional and time-resolved particle tracking with the Shake-The-Box (STB) algorithm in a long pipe experiment (length up to 20 m, with a diameter of D=28 mm) and use two types of particles having different diameters (0.1 – 0.4 D). By using hydrogel particles, we can simultaneously obtain the fluid and particle motion, including their rotation. Here we present our recent improvements of the STB-setup, which allows an increase of the field of view, a higher spatial resolution and a minimization of ghost tracks.