Source-term Characterization for three-phase Venting Scenarios

摘要

The participation of solid particles has a considerable impact on quality and quantity of the venting process. The two-/multi-phase onset is significantly shifted down to smaller filling levels. Particularly the small particle participation makes the venting process more violent. The reason is probably the increased surface area, which provides a large amount of the heterogeneous nuclei. The vapor formation rate is accordingly high to the amount of the nuclei, particularly in the first stage of venting process. The distinction between one- and two-/multi-phase discharge is very important because it determines the size and the design of the venting system. In addition, the total liquid mass discharge increases with solid mass fraction. During the depressurizing process the mixture content is shifted up by the large amount of vapor formed in the bottom area. Particularly in the first stage of the venting process the outlet flow has a low vapor content. A great amount of liquid mass is discharged. This discharge behavior has to be taken into account when sizing a vent. The appearing mass stream density has a significant impact on the vent size estimation.