DOI: 10.1615/TSFP2
LARGE-DOMAIN SIMULATIONS OF PLANE COUETTE AND POISEUILLE FLOW
摘要
Direct numerical simulations of turbulent Poiseuille and Couette flow have been carried out in very large computational domains at different Reynolds numbers. Two-point correlations of velocities, and the pre-multiplied energy spectra are used to study the large scale structures. The spanwise scale of large structures in plane Couette flow is constant in the channel central region. For Poiseuille flow, it is variable, but is found to collapse under a particular power law outer scaling. The pre-multiplied energy spectra clearly distinguish between peaks that scale on inner (wall) variables, and peaks that scale with channel variables. Couette flow is found to contain two peaks that are more pronounced than in Poiseuille flow. A secondary peak in the streamwise spectra varies in inner variables, while a secondary peak in the spanwise spectra varies in outer variables.