Interfacial momentum transfer due to phase change

The conventional formulas for the interfacial momentum transfer due to phase change are defined in Sect. 3.3 for the different averaging methods commonly applied in chemical reactor analysis. The modeling concepts usually adopted for the different averages are mathematically similar, so we choose to present a representative interfacial momentum transfer term in the framework of the volume averaging method described in Sect. 3.4.1. 

In fluid mechanics the interfacial momentum transfer due to phase change (3.153) is normally expressed in terms of interfacial mass flux weighted quantities  

The modeling of the interfacial mass transfer terms due to phase change Fvk is discussed in Sect. 5.2, so only the (v ) term is considered in this section. 

The same model assumption is used for gas-liquid interfaces as well, since the interface is hypothetically pictured as being stagnant [43]. However, one or both of the bulk phases may move. 

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The interfacial momentum transfer due to phase change is defined by ... 

The rather blurry picture of the gas-liquid interface makes it very difficult to parameterize the yk)Aj variable. Therefore, the interfacial momentum transfer due to phase change is generally neglected at these surfaces too. Further work is obviously required to improve our knowledge about these phenomena and to validate this model assumption. 

Interfacial momentum transfer due to phase change (N/m ) Interfacial momentum transfer caused by stresses (N/m ) Instantaneous mass flux of molecules of species of type c with respect to stationary coordinate axes (kg/m s)... 

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