Mass transport to channel and tubular electrodes under a turbulent flow regime

1 Mass transport to channel and tubular electrodes under a turbulent flow regime 

The description of mass transport to channel and tubular electrodes given in Sect. 2 was restricted to laminar conditions. Once Re 2000, the pattern of flow is no longer smooth and steady fluctuating, irregular (eddying) motions become superimposed on the main stream. Consequently, a complete theoretical description of mass transport, under such a regime, is impossible [149] and, as a result, empirical methods are introduced. In particular, a simplified representation of turbulence is afforded by consider- 

provided that the time-averages are considered over an adequate length of time, tT, that they become time-independent [149] 

That is to say that we work in terms of a fully developed turbulent flow profile, the form of which has been influenced by the fluctuations v x, vy, and v z. 

The fully developed turbulent velocity profile within the tubular electrode cell can satisfactorily be represented by the empirical equation [150, 151] 

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