  Modeling of pores generation in 2-D with granular grains using molecular
dynamics method is reported in this work. Grains with certain diameter
distribution are let falling due to gravity. Three configurations (larger
diameter on top, smaller diameter on top, and mixed) and two kinds of mixture
(same grains density and same grains mass) are used in the simulation. Mixture
with heterogen density gives higher porosity than the homogen one for higher
initial height, but change into opposite condition for lower initial height.
