Nonlinear eddy viscosity modeling and experimental study of jet spreading rates

Indoor Air ◽  
2013 ◽  
Vol 24 (1) ◽  
pp. 93-102 ◽  
Author(s):  
C. Heschl ◽  
K. Inthavong ◽  
W. Sanz ◽  
J. Tu
Keyword(s):  
Experimental Study ◽  
Eddy Viscosity ◽  
Viscosity Modeling ◽  
Spreading Rates

Analysis of Model Variance for Ensemble Based Turbulence Modeling

2015 ◽  
Vol 15 (2) ◽  
pp. 173-188 ◽  
Author(s):  
Nan Jiang ◽  
Songul Kaya ◽  
William Layton
Keyword(s):  
Eddy Viscosity ◽  
Turbulence Modeling ◽  
Turbulent Viscosity ◽  
Viscosity Coefficient ◽  
Unconditional Stability ◽  
Combined Approach ◽  
Time Stepping ◽  
Eddy Viscosity Model ◽  
Viscosity Modeling ◽  
The Ensemble Method

AbstractThis report develops an ensemble or statistical eddy viscosity model. The model is parameterized by an ensemble of solutions of an ensemble-Leray regularization. The combined approach of ensemble time stepping and ensemble eddy viscosity modeling allows direct parametrization of the turbulent viscosity coefficient. We prove unconditional stability and that the model's solution approaches statistical equilibrium as t → ∞; the model's variance converges to zero as t → ∞. The ensemble method is used to interrogate a rotating flow, testing its predictability by computing effective averaged Lyapunov exponents.

Experimental study on the restoration from a tilt-azimuth series for improvement in resolution

1995 ◽  
Vol 53 ◽  
pp. 636-637
Author(s):  
Norio Baba ◽  
Norihiko Ichise ◽  
Syunya Watanabe
Keyword(s):  
Experimental Study ◽  
Spherical Aberration ◽  
Incident Beam ◽  
Optical Parameters ◽  
Beam Tilting ◽  
Illumination Method ◽  
Restoration Method ◽  
Illumination Mode

The tilted beam illumination method is used to improve the resolution comparing with the axial illumination mode. Using this advantage, a restoration method of several tilted beam images covering the full azimuthal range was proposed by Saxton, and experimentally examined. To make this technique more reliable it seems that some practical problems still remain. In this report the restoration was attempted and the problems were considered. In our study, four problems were pointed out for the experiment of the restoration. (1) Accurate beam tilt adjustment to fit the incident beam to the coma-free axis for the symmetrical beam tilting over the full azimuthal range. (2) Accurate measurements of the optical parameters which are necessary to design the restoration filter. Even if the spherical aberration coefficient Cs is known with accuracy and the axial astigmatism is sufficiently compensated, at least the defocus value must be measured. (3) Accurate alignment of the tilt-azimuth series images.

An Experimental Study of Some Properties of Stuttered Words

1962 ◽  
Vol 5 (4) ◽  
pp. 387-394 ◽  
Author(s):  
Bruce Quarrington ◽  
Jerome Conway ◽  
Nathan Siegel
Keyword(s):  
Experimental Study
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