Fluid motion, mass transfer/transport liquid

In studying transport phenomena one is guaranteed to encounter situations involving fluid-solid or gas-liquid interfaces. These problems usually become more complex when fluid motion is involved. Traditionally, such complex problems are analyzed with the aid of the concept of a boundary layer. The boundary layer equations are well established for fluid flow, heat transfer, and mass transfer [8,9-13]. This set of equations is a convenient starting point for the scaling of the independent and dependent variables. However, before we begin it is helpful to briefly review descriptions of the three types of boundary layers. 

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