Liquid metal flow measurement by neutron radiography

Visualization of a liquid metal flow and image processing methods to measure the vector field are carried out by real-time neutron radiography. The JRR-3M real-time thermal neutron radiography facility in the Japan Atomic Energy Research Institute was used. Lead—bismuth eutectic was used as a working fluid. Particles made from a gold—cadmium intermetallic compound (AuCd3) were used as the tracer for the visualization. The flow vector field was obtained by image processing methods. It was shown that the liquid metal flow vector field was obtainable by real-time neutron radiography when the attenuation of neutron rays due to the liquid metal was less than 1/e and the particle size of the tracer was larger than one image element size digitized for the image processing.