Time development of energy spectrum in rotating inhomogeneous turbulence accompanied with helicity injection

Abstract

In rotating turbulent flows accompanied with spatially inhomogeneous distribution of helicity, it is known that statistically averaged flow spontaneously emerges. In this study, we investigate the phenomenon in terms of not only spatial transport of velocity but also inter-scale transport of kinematic energy in the wavenumber space. We perform a numerical simulation of rotating turbulence in a periodic box in which energy or helicity are driven in spatially confined region. As a result, the energy spectrum which is decomposed only in spatially homogeneous directions does not grow, while the mean velocity profile grows as the time goes by. On the energy spectrum which is defined by decomposing the total energy in the whole system, we can observe the growth of it in the lower wavenumber region than energy injection scale.