Rotational Effects on Layered Structures in Inhomogeneous Stratified Turbulence

Effects of buoyancy force stabilizing the disturbances and system rotation are investigated on turbulent structure of inhomogeneous flow. Fourier spectral method is used for inhomogeneous flow stirred by the artificial body force in the fringe region at the right side of the cuboid computational box of periodic boundary condition; thus stirred disturbances are dispersed from turbulent to non-turbulent flow field in the \(x_1\), i.e., streamwise direction. Moreover, a constant mean temperature gradient \(d \Theta /d x_3\) is imposed in the \(x_3\) direction i.e., vertical direction, to make a flow dynamically stable. As a result, internal gravity waves are radiated from the disturbed region, contributing to the dispersion of turbulent fluctuations, which generates the layered structures of \(u_1\), i.e., streamwise velocity elongated in the \(x_1\) direction. Moreover, system rotation imposed in the \(x_3\) direction results in an asymmetry between the positive and negative vertical vorticity; negative anticyclonic vorticity, surrounded by positive cyclonic vorticity, tends to become dominant flow structures.