| Autor: |
Melikhov, V. I., Melikhov, O. I., Volkov, G. Yu., Yakush, S. E., Salekh, B. |
| Zdroj: |
Thermal Engineering; Jan2023, Vol. 70 Issue 1, p63-72, 10p |
| Abstrakt: |
The penetration of a liquid jet into a space filled with another liquid for the case of large difference in density between these liquids is examined as applied to the fragmentation and mixing of jets during various accident scenarios at nuclear power plants (discharge of corium melt into water or water into a volume filled with liquid lead). The hydrodynamic equations for several immiscible liquids with sharp interfaces were solved using the Volume of Fluid (VOF) method. Mathematical models of multiphase flows, implemented numerically in the OpenFOAM open source package, are presented. A series of verification and research calculations was performed in a two-dimensional (plane) approximation, and the obtained results were compared with the published data. The results of calculation of the penetration of a Wood's metal melt jet into a deep water-filled vessel, performed using this approach, revealed successive stages in the evolution of a fragmenting jet. A good qualitative and quantitative agreement of the predictions with the published results of the calculation of this process by the ANSYS Fluent code were attained. The regularities of mixing of a water jet discharged into a volume filled with initially stagnant liquid (molten) lead are studied. It has been demonstrated that the fragmentation of the water jet occurs almost immediately after it enters the liquid lead in this case. The effect of the grid cell size on the characteristics of phase mixing was examined. The predicted characteristic sizes of the formed fragments, their dispersed composition, and the interfacial surface area during mixing are presented. Nomograms of the size distribution for the fragments formed during the jet breakup were plotted for both studied problems. It is shown that the melt fragments formed in this process are much smaller than the minimum limit size of melt droplets freely falling in water. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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