Affiliations: [a] Department of Physics, University of Latvia, Riga, Latvia | [b] Paul Scherrer Institut, Villigen, Switzerland
Correspondence:
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Corresponding authors: Mihails Birjukovs, Researcher, Laboratory for Modelling of Environmental and Technological Processes; Jelgavas street 3, LV-1004, Riga, Latvia. E-mail: mihails.birjukovs@lu.lv. Pavel Trtik, Instrument scientist NEUTRA, Paul Scherrer Institut; Forschungsstrasse 111, 5232 Villigen, PSI, Switzerland. E-mail: pavel.trtik@psi.ch
Abstract: This paper presents detailed results of neutron imaging of argon bubble flows in a rectangular liquid gallium vessel with and without the application of external horizontal magnetic field. The developed image processing algorithm is presented and its capability to extract physical information from images of low signal-to-noise ratio is demonstrated. Bubble parameters, velocity components, trajectories and relevant statistics were computed and analyzed. A simpler version of the code was applied to the output of computational fluid dynamics simulations that reproduced the experiment. This work serves to further validate the neutron radiography as a suitable method for monitoring gas bubble flow in liquid metals, as well as to outline procedures that might help others to extract data from neutron radiography images with a low signal-to-noise ratio resulting from high frame rate acquisitions required to resolve rapid bubble motion.
