Diffusion Wake at High Peclet Numbers

In the outer region e, the concentration is constant and is equal to its undisturbed values at infinity. 

In the diffusion boundary layer d, in the mass transfer equation one can neglect molecular tangential diffusion transfer compared with the diffusion in the radial direction the convective terms are retained (but somewhat simplified by linearization near the interface). The concentration distribution in that region was obtained earlier in Section 4.6. 

In the convective-boundary layer region W(1) of the diffusion wake, molecular diffusion can be neglected. The concentration here depends only on the 

In the internal wake region W(2), one can neglect molecular mass transfer in the radial direction. 

In the rear stagnation region W(3), the mass transfer equation can be somewhat simplified. In doing so, one must take into account convective terms as well as the radial and tangential molecular diffusion components. 

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