Mass transfer rate single-screw extruder

A specific expression for the mass transfer rate in Eq. (11) was first developed by Latinen (1962) in a classic paper that showed how penetration theory can be applied to the analysis of devolatilization processes in single-screw extruders. The derivation presented here parallels that by Latinen but differs in some respects for reasons of clarity. 

The same assumptions and equations used in developing an expression for kialob for single-screw extruders can be used to describe mass transfer rates in the type of corotating twin-screw extruder considered here. In this regard. Fig. 14 is relevant, and ki a/ob will be given by Eq. (53) ... 

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