Vjacheslav Somsikov

The evolution of the non-equilibrium colliding hard disk systems in the velocity space has been studied using a mathematical model based on the collision matrix. It has been shown that the main features of evolution can be determined by the property of the collision matrix. The characteristic parameter which defines the maximal possible velocity at which the system approaches to the equilibrium state was calculated. This parameter decreases as the number of collision increases. It has been found how the evolution of the hard disk systems to the equilibrium can be described in terms of the distribution function of impact parameters of colliding disks. Is shown, that the condition of inhomogeneiaty of impact parameters causes reduction with growth of number of collisions total on all colliding pairs sum of a difference of speeds of colliding disks. It is equivalent to aspiration to zero the total internal force of collisions of disks.