Tomographic X-ray particle tracking velocimetry

Journal Article · 22 December 2021 · Experiments in Fluids

DOI: https://doi.org/10.1007/s00348-021-03362-w · OSTI ID:1897631

Mäkiharju, Simo A.  ^[1]; Dewanckele, Jan ^[2]; Boone, Marijn ^[2]; Wagner, Christian ^[3]; Griesser, Andreas ^[3]

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1. University of California, Berkeley, CA (United States)
2. Tescan, Ghent (Belgium)
3. Math2Market GmbH, Kaiserslautern (Germany)

We investigate the feasibility of in-laboratory tomographic X-ray particle tracking velocimetry (TXPTV) and consider creeping flows with nearly density matched flow tracers. Specifically, in these proof-of-concept experiments we examined a Poiseuille flow, flow through porous media and a multiphase flow with a Taylor bubble. For a full 360° computed tomography (CT) scan we show that the specially selected 60 micron tracer particles could be imaged in less than 3 seconds with a signal-to-noise ratio between the tracers and the fluid of 2.5, sufficient to achieve proper volumetric segmentation at each time step. In the pipe flow, continuous Lagrangian particle trajectories were obtained, after which all the standard techniques used for PTV or PIV (taken at visible wave lengths) could also be employed for TXPTV data. And, with TXPTV we can examine flows inaccessible with visible wave lengths due to opaque media or numerous refractive interfaces. In the case of opaque porous media we were able to observe material accumulation and pore clogging, and for flow with Taylor bubble we can trace the particles and hence obtain velocities in the liquid film between the wall and bubble, with thickness of liquid film itself also simultaneously obtained from the volumetric reconstruction after segmentation. While improvements in scan speed are anticipated due to continuing improvements in CT system components, we show that for the flows examined even the presently available CT systems could yield quantitative flow data with the primary limitation being the quality of available flow tracers.

• Research Organization: Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF)
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 1897631
• Journal Information: Experiments in Fluids, Journal Name: Experiments in Fluids Journal Issue: 1 Vol. 63; ISSN 0723-4864
• Publisher: SpringerCopyright Statement
• Country of Publication: United States
• Language: English