Study on dispersed phase tracking method for time series 3-dimensional interface data

Horiguchi, Naoki   ; Yamamura, Sota*; Yoshida, Hiroyuki  ; Abe, Yutaka*

Specific measurement methods have been developed to understand multi-phase thermal-hydraulic behavior. By using these methods, we can obtain time series two and 3-dimensional spatial interface data of phases. These data are useful for providing validation data for advanced simulation methods based on multi-fluid computation fluid dynamics. For example, to understand FCI (fuel coolant interaction) behavior, specific measurements for fragments (dispersed phase) generated from the jet were measured, and interface and size of fragments were successfully evaluated. However, 3-dimensional data for velocity was not assessed, because there is no tracking method for individual dispersed phases like a tracking method of PTV (particle tracking velocimetry), which using time series 2-dimensional data. In this paper, we developed the dispersoid phase tracking method based on time series 3-dimensional interface data. To check the applicability of this method for 3-dimensional interface data, we used detailed two-phase simulation data by using TPFIT. In these data, there are 3-dimensional data of both interface and velocity distribution. Then, we can evaluate the correct dispersed phase velocity, and we can consider the accuracy of the developed method precisely. In this paper, we applied the developed method to simplified two-phase flow. The simplified flow means not to include coalescence and fragmentation of dispersoids. As a result, the tracking of one dispersoid performed successfully, but a standard deviation of the measuring error increased with the decrease of cell number of the dispersoid.