Neutron Radiography Visualization of Solid Particles in Stirring Liquid Metal

Abstract

This paper presents the analysis of the first dynamic neutron radiography experiment that visualized motion of solid particles in liquid metal, which was stirred by a system of four counter-rotating magnets. The paper also contains the quantitative results derived from neutron images: the distribution of particle concentration, number of admixed particles and velocities as functions of the magnet rotation speed.

800 fps neutron radiography of air-water two-phase flow

“…The negligible readout-time and low read-out noise of sCMOS cameras allow for the “continuous” observation of non-cyclic processes with high-temporal resolution. A few examples of high temporal resolution neutron imaging of industrially relevant samples utilizing the sCMOS technology include: the visualization of flows in liquid metals with acquisition time of approximately 0.03 s in 2D [1], and on-the-fly tomography of water uptake in roots [2]. An overview of the high-temporal resolution imaging for studies of porous media has been recently published by Kaestner et al [3].…”

Argon bubble flow in liquid gallium in external magnetic field

“…Optimization of industrial processes requires both simulations and suitable experimental methods. Neutron radiography is, in the context of high frame rate flow monitoring, a relatively new and promising technique that can probe optically opaque liquid metals directly [5] in the sense that, in addition to qualitative observations and image-based velocimetry, it enables the study of bubble shape dynamics and characteristic oscillation frequencies, which are important comparison criteria for verification of computational fluid dynamics (CFD) models. For some higher-Z metals, neutron imaging, being conceptually similar to X-ray imaging, is more appropriate, enabling one to work with thicker (i.e.…”

“…For some higher-Z metals, neutron imaging, being conceptually similar to X-ray imaging, is more appropriate, enabling one to work with thicker (i.e. more representative) samples [5,6]. This is especially important for suppressing the influence of bubble-wall interactions.…”

“…To date, several noteworthy studies employing neutron radiography have been conducted, but most were focused on single phase flow analysis using tracer particles [5,6], solidification dynamics [6], or performed only qualitative analysis of bubble flows. Notable exceptions include the work by Zboray et al [8,9,10], wherein image processing and phase tracking algorithms were implemented and flow assessed by neutron radiography was given a quantitative treatment.…”

100 Hz neutron radiography at the BOA beamline using a parabolic focussing guide

“…The examples of high temporal resolution neutron imaging of industrially relevant samples utilizing the sCMOS technology include: the visualization of flows in liquid metals with temporal resolution of approximately 0.03 s in 2D [1] , and on-the-fly tomography of water uptake in roots with sub-minute resolution in 3D [2] . An overview of the high-temporal resolution imaging for studies of porous media has been recently provided by Kaestner et al [3] .…”