Effective-medium theory of diffusion and chemical reactions in the presence of stationary overlapping sinks

✍ Scribed by Jens Krüger

• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 500 KB
• Volume: 182
• Category: Article
• ISSN: 0378-4371
• DOI: 10.1016/0378-4371(92)90225-f

✦ Synopsis

We calculate the effective reaction rate constant k* and the effective diffusion constant D* for a system of independently distributed overlapping sinks as functions of the volume fraction ~b of the sinks and the Sherwood number Sh. The Sherwood number characterises the strength of the reaction on the sink surfaces. We use the effective-medium theory, which has been presented in two previous papers. A comparison of these results with those we have previously obtained for non-overlapping imperfect sinks shows that in an interval [0, ~b .... Sh] the calculated values of k* for overlapping sinks lie above those for the non-overlapping ones. On the other hand, since the total reactive surface at a given 4~-value is larger for non-overlapping traps the effective reaction rate should also be larger in this case for all <b. This leads to the conclusion that the observed discrepancy stems from the approximation of the pair distribution function by the first term of its virial expansion, which we used in a previous paper.