The dissipation rate coefficient of turbulence is not universal and depends on the internal stagnation point structure

The energy dissipation rate coefficient of statistically stationary homogeneous isotropic turbulence depends on the external force sustaining the turbulence irrespective of Reynolds number. This nonuniversality is established by proving that the Taylor length is proportional to the mean distance between stagnation points and thereby relating the energy dissipation rate coefficient to the stagnation point structure of the turbulence which is shown to depend on the structure of the large eddies. Confirmation of these relations is obtained at moderate Reynolds numbers by a series of direct numerical simulations where the large-scale forcing is systematically varied.