Physikalisch-Technische Bundesanstalt, 10587 Berlin, Germany.
J Chem Phys. 2009 Dec 7;131(21):214102. doi: 10.1063/1.3265987.
An effective medium theory that can be used to calculate effective diffusion and reaction rate coefficients in random heterogeneous reaction-diffusion systems is described. The predictions of the theory are compared with simulations of spatially distributed media with different types of heterogeneity. The magnitude of the front velocity in bistable media is used to gauge the accuracy of the theoretical predictions. Quantitative agreement is found if the diffusion length in the heterogeneities is large compared to the characteristic width of the front. However, for small diffusion lengths the agreement depends on the type of heterogeneity. The effective medium predictions are also compared with simulations on systems with regular or temporal disorder.
描述了一种可用于计算随机非均相反应-扩散系统中有效扩散和反应速率系数的有效介质理论。将理论预测与具有不同类型非均质性的空间分布介质的模拟进行了比较。双稳介质中前沿速度的大小用于衡量理论预测的准确性。如果在非均相中的扩散长度与前沿的特征宽度相比足够大，则可以找到定量的一致性。然而，对于小的扩散长度，一致性取决于非均质性的类型。还将有效介质预测与具有规则或时间无序的系统的模拟进行了比较。
