title: Multiple invaded consolidating materials.
abstract: We study a multiple invasion model to simulate corrosion or intrusion processes. Estimated values for the fractal dimension of the invaded region reveal that the critical exponents vary as a function of the generation number G , i.e., with the number of times the invasion process takes place. The averaged mass M of the invaded region decreases with a power law as a function of G , M approximately Gbeta , where the exponent beta approximately 0.6 . We also find that the fractal dimension of the invaded cluster changes from d(1) =1.887+/-0.002 to d(s) =1.217+/-0.005 . This result confirms that the multiple invasion process (for the case in which uninvaded regions are forbidden) follows a continuous transition from one universality class (nontrapping invasion percolation) to another (optimal path). In addition, we report extensive numerical simulations that indicate that the mass distribution of avalanches P (S,L) has a power-law behavior and we find that the exponent tau governing the power-law P (S,L) approximately S-tau changes continuously as a function of the parameter G . We propose a scaling law for the mass distribution of avalanches for different number of generations G .
authors.affiliation: Departamento de Física, Universidade Federal do Ceará, 60451-970 Fortaleza, Ceará, Brazil.
authors.forename: A D
authors.initials: AD
authors.lastname: Araújo
authors.forename: J S
authors.initials: JS
authors.lastname: Andrade
authors.forename: H J
authors.initials: HJ
authors.lastname: Herrmann