  The filtration of fluid in 2D porous medium is simulated by the molecular
dynamics technique. The high concentration of fluid is created at the initial
point in time and the number of fluid particles is investigated in all porous.
The concentration of particles pores and parameters of interaction potentials
is varied. In all cases the particles concentration decay is well described by
exponential functions. The decreasing of the interpore channels leads to the
increasing of the relaxation time and does not depend on the system size. This
phenomenon is observed in real filtration processes.
