Spherical Cavity Filled by a Stagnant Medium

For a first-order volume reaction at Pe = 0, the exact closed-form solution of our problem reads 

For an nth-order volume reaction, one can calculate the mean Sherwood number [360] by the approximate formula 

Mass and Heat Transfer Under Complicating Factors 

For n = 1, formula (5.4.3) gives the exact result (5.4.2). The comparison of the approximate expression (5.4.3) with the results of the numerical solution of the inner problem (5.3.1), (5.3.2) for nth-order reactions with n = 1/2 and n = 2 reveals an error of 5% in the entire range of the parameter kv. 

For an arbitrary dependence of the rate of volume chemical reaction on the concentration, it is expedient to use the approximate formula 

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