Effect of two liquid phases on level swell

The presence of two liquid phases is likely to cause a fluid to be inherently foamy and so give rise to homogeneous vessel behaviour. 

C F Parry, Relief Systems Handbook , IChemE, Rugby, 1994, ISBN 0 85295 267 8 

H G Fisher et al., Emergency Relief System Design Using DIERS 

BS 6759 Part 3 1984, Specification of Safety Valves for Process Fluids , BSI, 1984 

API RP 520, Sizing, selection and installation of pressure relieving devices in refineries, Part 1 sizing and selection , API, 1993 

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