Large-scale bottleneck effect in two-dimensional turbulence

TL;DR

This paper demonstrates a large-scale bottleneck effect in two-dimensional turbulence caused by friction, linking it to energy condensation and discussing implications for turbulence modeling.

Contribution

It reveals a large-scale bottleneck in 2D turbulence due to friction, a phenomenon not previously characterized, and discusses its impact on energy spectrum and turbulence structures.

Findings

Large-scale bottleneck observed in 2D turbulence due to friction.

Bottleneck linked to energy condensation at domain size wavenumbers.

Careless hypofriction use may reduce inertial range.

Abstract

The bottleneck phenomenon in three-dimensional turbulence is generally associated with the dissipation range of the energy spectrum. In the present work, it is shown by using a two-point closure theory, that in two-dimensional turbulence it is possible to observe a bottleneck at the large scales, due to the effect of friction on the inverse energy cascade. This large-scale bottleneck is directly related to the process of energy condensation, the pile-up of energy at wavenumbers corresponding to the domain size. The link between the use of friction and the creation of space-filling structures is discussed and it is concluded that the careless use of hypofriction might reduce the inertial range of the energy spectrum.