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[hollerg]

Often pressure relief systems must deal with 2 phase flow that results from liquid swell (boiling throughout the vessel). I imagine this is a somewhat transient/dynamic issue, like opening a can of soda.

I was wondering if anyone had a method or reference that discussed limiting or prevention of swell induced or vapor-liquid boilover?

I guess what I imaging I am looking for are correlations for pressure change and or heat flux that can be used to establish a prudent rate of change for constraints using the physical properties of the fluid and geometry of the vessel.

Thanks for considering my question.

hollerg

[Adriaan]

Reboiling of condensate is - relatively speaking - the easiest example of your problem. The reason it is the easiest example is that the properties of water and steam (see the Excel plugin on the main Cheresources site) can be calculated relatively easily whereas for other media the required data can be rather harder to obtain.

What that means is that the "correlations for pressure change and (no or!) heat flux" are too specific (for the product involved), especially when a change of phase is involved*, to give a general figure!




I also disagree with your assumption that it is a transient problem; in condensate systems reboiling can occur in many locations (wherever there are changes in the resistance; widening pipes, narrower pipes, appendages, pipe junctions). A change in one part of an installation can therefore significantly influence what happens in another connected part of an installation.



* to return to the water - steam example; steam and water have different specific heat transfer coefficients, densities etcetera. This means that when there is a phase change you are in effect dealing with a mixture of two different media.