Spatial mapping of velocity power spectra in Taylor-Couette flow using ultrafast NMR imaging

Abstract

Ultrafast NMR imaging was used to clarify spatiotemporal structures of wavy Taylor-Couette flow. NMR images designed to give a radial velocity distribution in a cross-sectional plane containing the rotation axis were successively taken at 200 ms time intervals. Distributions of velocity power-spectral components were obtained by temporal Fourier transform of the sequential velocity images. The obtained spectral maps clearly visualized the spatial structures of the wavy components in the cross-sectional plane.