Stirring and mixing time

The dimensional dependence of the mixing time, tm, is similar to that [9.19] of the mechanical power consnmed, except that the molecnlar diffusion of products is added thought the Schmidt number Sc = v/v. We, therefore, write  

The mixing time,, is defined by a criterion stipulating the level of mixing that will be deemed sufficient. It is in general considered that the constituents are mixed if the variance of the concentration is less than a certain value. By including the diffusivity of products, formulation [9.24] is very general. It takes into account the 

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