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A rapid-pressure correlation representation consistent with the Taylor-Proudman theorem materially-frame-indifferent in the 2D limitA nonlinear representation for the rapid-pressure correlation appearing in the Reynolds stress equations, consistent with the Taylor-Proudman theorem, is presented. The representation insures that the modeled second-order equations are frame-invariant with respect to rotation when the flow is two-dimensional in planes perpendicular to the axis of rotation. The representation satisfies realizability in a new way: a special ansatz is used to obtain analytically, the values of coefficients valid away from the realizability limit: the model coefficients are functions of the state of the turbulence that are valid for all states of the mechanical turbulence attaining their constant limiting values only when the limit state is achieved. Utilization of all the mathematical constraints are not enough to specify all the coefficients in the model. The unspecified coefficients appear as free parameters which are used to insure that the representation is asymptotically consistent with the known equilibrium states of a homogeneous sheared turbulence. This is done by insuring that the modeled evolution equations have the same fixed points as those obtained from computer and laboratory experiments for the homogeneous shear. Results of computations of the homogeneous shear, with and without rotation, and with stabilizing and destabilizing curvature, are shown. Results are consistently better, in a wide class of flows which the model not been calibrated, than those obtained with other nonlinear models.
Document ID
19940022932
Acquisition Source
Legacy CDMS
Document Type
Contractor Report (CR)
Authors
Ristorcelli, J. R.
(Institute for Computer Applications in Science and Engineering Hampton, VA, United States)
Lumley, J. L.
(Cornell Univ. Ithaca, NY., United States)
Abid, R.
(High Technology Corp. Hampton, VA., United States)
Date Acquired
September 6, 2013
Publication Date
January 1, 1994
Subject Category
Fluid Mechanics And Heat Transfer
Report/Patent Number
ICASE-94-1
AD-A277582
NAS 1.26:191591
NASA-CR-191591
Report Number: ICASE-94-1
Report Number: AD-A277582
Report Number: NAS 1.26:191591
Report Number: NASA-CR-191591
Accession Number
94N27435
Funding Number(s)
PROJECT: RTOP 505-90-52-01
CONTRACT_GRANT: NAS1-19480
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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