Particle tracking velocimetry using fast x-ray phase-contrast imaging

The authors demonstrate the use of millisecond x-ray phase-contrast imaging for velocity measurement of particle-laden flows in an optically opaque vessel. Taking advantage of particle size polydispersity, this single-particle tracking approach is extremely effective on flows with tracer particles exhibiting a great size distribution ranging from 1 mu m to hundreds of micrometers, which is impossible for visible-light-based techniques. Furthermore, a tomographic reconstruction was applied to yield the three-dimensional flow velocity field and its particle size dependence with unprecedented sensitivity. (c) 2007 American Institute of Physics.