Effect of shear stress on wave deformation on jet interface

Masaki, Naoto*; Kaneko, Akiko*; Horiguchi, Naoki   ; Yoshida, Hiroyuki  

During severe accidents in light water reactors, molten fuel jets into the coolant pool and are atomized. The cooling of molten fuel occurs at the interface between the fuel and coolant and is enhanced by the increase of interface area with atomization. To achieve the stable cooling of molten fuel, it is important to understand the deformation of interface waves during atomization and the role of interfacial shear stress, which is indicated as a primary factor in previous studies. However, due to technical limitations imposed by heat and fluid properties, visualizing the interface shape and measuring shear stress in experiments using molten fuel is difficult. Therefore, this study enabled the calculation of interface shear stress by simultaneously obtaining the interface shape using the 3D-LIF method and the velocity field using using the multi-section PIV in simulated experiments. This presentation reports on the results of investigating the effect of shear stress on the deformation of interface waves based on the obtained data.