Scale-Induced Closure for Approximations of Kinetic Equations.

The order-of-magnitude method proposed by Struchtrup is a new closure procedure for the infinte moment hierarchy in kinetic theory of gases. We outline a generalization of the procedure and derive a formal theory of scale-induced closures on the level of the kinetic equation. The new closure produces a moment distribution function that respects the scaling of a Chapman-Enskog expansion. The structure of the non-equilibrium part of the distribution is induced by the collision operator. We investigate accuracy and stability of the new closure. Examples illustrate the new approach. [ABSTRACT FROM AUTHOR]