The formation and characterization of dust layers are of great significance in many process-engineering sectors. This report presents a computer simulation with which the creation and growth of a dust cake can be modeled during the filtration via particle trajectory calculations. The influence on the gas Bow field exerted by those particles which have already been deposited is taken into account in a macroscopic way. The input parameters include the size distribution of the raw-gas particles, the separation characteristics of the clean filter medium and the filter face velocity. The output parameters include the local dust cake porosities, the time-dependent pressure loss and fractional separation efficiency trends, together with the clean-gas particle concentration.