Lévy Distribution of Collisions for Knudsen Diffusion in Fractal Pores
We show on a specific example a few anomalous properties of Knudsen diffusion in two dimensional irregular porous catalysts. The geometrical irregularity is modeled by prefractal shapes. The probability distribution of the number of collisions is found to obey a power law of the Lévy type with an exponent ≈ −2. A remarkable result is that the distribution does not change significantly between specular and random reflection in deterministic prefractals.
KeywordsPorosity Catalysis Eter Ballistic Trajectory
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