| A turbulent annular swirling liquid contiguous wall jet is characterized experimentally in a "vortex tube". The flow is proposed for use in a thick liquid first-wall chamber concept for inertial fusion power plants. The three components of planar velocity vector fields are measured with a newly implemented single camera split-screen stereoscopic particle image velocimetry scheme. The combined use of fluorescent particles and thick sharp cut-off filters effectively blocks glare reflected from the liquid-air interface. Flow field measurements in the vicinity of a free surface are thus successfully obtained in the presence of strong surface irregularities that have been avoided in free surface turbulence experiments so far. One- and two-point velocity correlations are used to characterize the turbulence development. Large transitional vortical structures are identified.; During the course of the experiment, two classes of oils have been identified that allow the simulation of liquid fluoride salts with an unprecedented similarity. Liquid fluoride salts have desirable properties for use as working fluids for high-temperature (500°C--1000°C) heat transport in fission and fusion applications. By adjusting the length, velocity, average temperature and temperature difference scales of the experiment, it is possible to simultaneously match the prototypical Reynolds (Re), Froude (Fr), Prandtl (Pr) and Grashof (Gr) numbers in a 40% reduced scale experiment that requires less than 2% of the prototype pumping and heating power.; Finally, in parallel to the annular jet characterization, spinning liquid layers are designed and developed for additional applications to thick-liquid first wall protection in fusion power plant designs. |
