NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
Numerical Study of Rotating Turbulence with External ForcingDirect numerical simulation at 256(exp 3) resolution have been carried out to study the response of isotropic turbulence to the concurrent effects of solid-body rotation and numerical forcing at the large scales. Because energy transfer to the smaller scales is weakened by rotation, energy input from forcing gradually builds up at the large scales, causing the overall kinetic energy to increase. At intermediate wavenumbers the energy spectrum undergoes a transition from a limited k(exp -5/3) inertial range to k(exp -2) scaling recently predicted in the literature. Although the Reynolds stress tensor remains approximately isotropic and three-components, evidence for anisotropy and quasi- two-dimensionality in length scales and spectra in different velocity components and directions is strong. The small scales are found to deviate from local isotropy, primarily as a result of anisotropic transfer to the high wavenumbers. To understand the spectral dynamics of this flow we study the detailed behavior of nonlinear triadic interactions in wavenumber space. Spectral transfer in the velocity component parallel to the axis of rotation is qualitatively similar to that in non-rotating turbulence; however the perpendicular component is characterized by a greatly suppressed energy cascade at high wavenumber and a local reverse transfer at the largest scales. The broader implications of this work are briefly addressed.
Document ID
19990009118
Acquisition Source
Langley Research Center
Document Type
Preprint (Draft being sent to journal)
Authors
Yeung, P. K.
(Georgia Inst. of Tech. Atlanta, GA United States)
Zhou, Ye
(Institute for Computer Applications in Science and Engineering Hampton, VA United States)
Date Acquired
September 6, 2013
Publication Date
August 1, 1998
Subject Category
Fluid Mechanics And Heat Transfer
Report/Patent Number
NAS 1.26:208702
NASA/CR-1998-208702
ICASE-98-39
Funding Number(s)
CONTRACT_GRANT: NAS1-97046
PROJECT: RTOP 505-90-52-01
CONTRACT_GRANT: NAS1-19480
CONTRACT_GRANT: NSF CTS-93-07973
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
No Preview Available