Distribution of Matter Introduced Into a Fluid Flow

6 Distribution of Matter Introduced Into a Fluid Flow 1133 

Integration of over the surface gives the total flux toward the particle for the case Pen 1  

Of special interest is the diffusion flux to the surface of a drop with internal viscosity ji. This problem has been considered in [3], The main difference from dif fusion toward a rigid particle is in the necessity to take into account the possibility of liquid slippage over the drop surface due to the motion of liquid within the drop. For the case when the substance is adsorbed on the surface but does not penetrate it, the expression for the diffusion flux at the surface has the form  

Comparing the expressions for diffusion flux onto a solid (6.104) and a liquid (6.110) particle, one can conclude that, all other things equal, the flux toward a hquid particle exceeds the flux toward a sohd one. This is a consequence of more favorable conditions for substance delivery to the surface of liquid, as mixing of solution takes place near the drop surface. 

The solution of problems on convective diffusion toward particles at finite Re and Pep numbers, was well as for boundary conditions more general than (6.93), can be found in work [13]. 

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