Kollisionskühlung in elektrisch geladener granularer Materie
Particles in granular systems collide inelasticly and kinetic energy is dissipated in the granular system. Granular temperature measures the unordered relative motion of the particles. As a result of the inelastic collisions granular temperature decreases, this process is called collisional cooling. In most cases granular particles are charged. This thesis studies the influence of electrical charges on the collisional cooling by using computer simulations and kinetic theory. It is shown, that electrical charge modifies the dissipation rate by a Boltzmann-factor. The energy barrier of the Boltzmann-factor is given by the electrostatic interaction of two colliding particles. In dense systems this energy barrier is reduced due to the interactions with the particles, that do not take part in the collision. A quantitative expression is given for the effective reduction of the energy barrier. The results found for homogeneous systems is expanded for the local description of inhomogeneous systems.