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Correlation length by measuring empty space in simulated aggregates

R. M. L. Evans·M. D. Haw
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Abstract

We examine the geometry of the spaces between particles in diffusion-limited cluster aggregation, a numerical model of aggregating suspensions. Computing the distribution of distances from each point to the nearest particle, we show that it has a scaled form independent of the concentration phi, for both two- (2D) and three-dimensional (3D) model gels at low phi. The mean remoteness is proportional to the density-density correlation length of the gel, xi, allowing a more precise measurement of xi than by other methods. A simple analytical form for the scaled remoteness distribution is developed, highlighting the geometrical information content of the data. We show that the second moment of the distribution gives a useful estimate of the permeability of porous media.

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R. M. L. Evans, M. D. Haw. 2002-02-12. Correlation length by measuring empty space in simulated aggregates. https://doi.org/10.1209/epl%2Fi2002-00278-2

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