Progress of the liquid sublayer thickness measurement during the onset of DNB in subcooled flow boiling

Nguyen, T. B.; 柴本 泰照 ; 佐藤 聡 ; 大川 富雄*

Nguyen, T. B.; Shibamoto, Yasuteru; Satou, Akira; Okawa, Tomio*

Knowledge of the liquid sublayer thickness (LST) that exists as macro-layer between the bubble and the wall is crucial for evaluating DNB heat flux in subcooled flow boiling. A previous report suggested that the LST can be measured using the confocal displacement sensor. However, the data discontinuity by the sensor and the large discrepancy with the available correlations are remaining obstacles for this measurement. To address these issues, a new laser displacement sensor has been used with an additional two high-speed cameras for the test section's side-view and front-view. This setup resolves the source of discontinuity in the data and provides the data with good agreement with existing correlations.