A RADIOSCOPIC TECHNIQUE TO STUDY CONVECTIVE FLUID-DYNAMICS IN OPAQUE LIQUID-METALS

Experimental verification of theoretical investigations into the behav iour of liquid metal convective flows is required to validate analytic al models and numerical simulation codes. A real-time radioscopic dens ity visualization system has been developed and is beginning to provid e useful data. The X-ray facility for studying opaque low-Prandtl-numb er fluid flow is described. Density changes as low as 10(-3) g cm(-3) can be visualized by careful control of scatter radiation. The new cap ability is demonstrated with natural convection benchmark experiments in a narrow vertical layer of gallium melt of aspect ratio A = 1.4. Th e density field in that cell is three-dimensional. Good agreement betw een calculations and experiments is obtained. Experiments with solidif ication are provided for further theoretical use.