Transient mass and heat exchange

Suppose that at the initial time t = 0 the concentration in the continuous medium is constant and is equal to C and that a constant surface concentration Cs is maintained for t 0. The transient mass exchange between a particle and a stagnant medium is described by the equation 

For nonspherical particles, the mean Sherwood number can be approximated by the expression 

For nonspherical particles, one can obtain Shst by using Table 4.2 and the expression (4.3.8). 

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