Rotating Effects on Energy Transfer Mechanism of Isotropic Turbulence

Turbulent flows in rotating systems have significant implications across diverse fields, spanning from climate systems, and ocean currents, to turbomachinery. While previous research has primarily focused on homogenous turbulence and its impact on mean flow under rotation, the energy transfer mechanisms between scales and energy budget in rotating turbulence remain undefined, particularly analyzed using experimental measurements taken in non-inertial systems. In this study, we developed a novel rotating platform capable of achieving a wide range of experimental conditions. With an onboard 4-camera tomographic PIV system, we investigate the 3D flow structure of isotropic turbulence under different rotation conditions in the non-inertial system. The presence of centrifugal force and Coriolis force induces distinct asymmetry in mean flow and isotropy. Additionally, the energy transfer mechanism, analyzed by velocity spectra, is also affected by these forces in different directions. The velocity spectra along different directions in the rotating setting shows the difference and deviates from the Kolmogorov -5/3 power law observed in non-rotating isotropic turbulence.