The larger dissipation
at the smaller ε reduces the collisional generation of temperature
and thus enhances the relative importance of the streaming
mechanism, leading to larger temperature anisotropies. Note
that while higher order kinetic theories can produce normal
stress differences [46,47], they are strictly only valid in the limit
ν→0; furthermore, they predict that the differences are
functions only of the inelasticity and are independent of the
concentration.