| 초록 |
Understanding Onset of Significant Void (OSV) is important in predicting Critical Heat Flux (CHF) phenomena accurately. A database of OSV in forced convection subcooled boiling is developed for various coolants (Water, R-22, etc.). The database consisted of the following parametric range: 1 ≤ P ≤ 140 bar, 27.5 ≤ G ≤ 11123.76 kg/m2s, 0.006 ≤ Q ≤ 4.2 MW/m2. The database also comprised of data of bubble detachment as well as the Onset of Flow instability (OFI) data, which are equally applicable to OSV conditions. Saha-Zuber model (1974) is determined to be not quite satisfactory in low-flow boiling conditions (Bartel et al., 2001). Furthermore, Levy model (1967) is more accurate than Saha–Zuber model in predicting the OSV in low-flow subcooled boiling condition (Sun et al. 2003). In this study, currently available OSV models are compared and analyzed as well as factors influencing in predicting OSV are discussed. For example, in Saha and Zuber model, hydraulic diameter is more significant than flow rate. In conclusion, Saha and Zuber model is the best-fitting OSV correlation in among the models studied within this database. |
