Results 121 to 130 of about 102,404 (168)

Gradient Richardson number profiles using SAS

Environmental Software, 1990
Abstract A short computer code is presented to determine the gradient Richardson number from tower measurements of wind and temperature. The gradient Richardson number is a useful parameter to determine whether sublayers of the atmospheric boundary layer are laminar or turbulent.
A.H. Weber, R.J. Kurzeja
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On an instability to Langmuir circulations and the role of Prandtl and Richardson numbers

Journal of Fluid Mechanics, 2001
The instability of a weakly sheared density-stratified two-dimensional wavy flow to longitudinal vortices is considered. The instability mechanism is Craik–Leibovich type 2, or CL2, and the problem is posited in the context of Langmuir circulations beneath irrotational wind-driven surface waves.
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Nonlinear instability of elementary stratified flows at large Richardson number

Chaos: An Interdisciplinary Journal of Nonlinear Science, 2000
Elementary stably stratified flows with linear instability at all large Richardson numbers have been introduced recently by the authors [J. Fluid Mech. 376, 319–350 (1998)]. These elementary stratified flows have spatially constant but time varying gradients for velocity and density. Here the nonlinear stability of such flows in two space dimensions is
Majda, Andrew J., Shefter, Michael G.
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Measurement of Prandtl Number as a Function of Richardson Number Avoiding Self-Correlation

Boundary-Layer Meteorology, 2009
The empirical dependence of turbulence Prandtl number (Pr) on gradient Richardson number (Ri) is presented, derived so as to avoid the effects of self-correlation from common variables. Linear power relationships between the underlying variables that constitute both Pr and Ri are derived empirically from flux and profile observations.
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Effects of Reynolds number and Richardson number on thermal stratification in hot plenum

Nuclear Engineering and Design, 1987
Thermal transient water tests were performed using a simplified hot plenum model of a pool-type LMFBR to examine the fundamental characteristics of thermal stratification during reactor trips. These tests were divided into two series to clarify the effects of (1) Reynolds number and (2) Richardson number on the behavior of thermal stratification.
S Moriya, N Tanaka, N Katano, A Wada
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Relation of Richardson number to the curvature of the wind profile

Boundary-Layer Meteorology, 1979
Values of Richardson number (Ri) and the wind profile curvature (β) in the atmospheric surface layer are evaluated from experimental data. The relationship between Ri and β shows some scatter, but gives agreement with the theoretical relation derived by Businger et al. (1971).
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THE RICHARDSON NUMBER IN THE PLANETARY BOUNDARY LAYER

1966
Abstract : Determination of the stability regime is a basic approach in any investigation of atmospheric turbulence. The establishment of stability criteria in the boundary layer is usually accomplished by use of the nondimensional Richardson number. The computation of accurate Richardson numbers is shown to be adversely affected by a number of factors
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Low Richardson Number in the Tropical Cyclone Outflow Layer

Journal of the Atmospheric Sciences, 2014
Abstract Dropsondes from the NOAA G-IV aircraft were used to examine the presence of low bulk Richardson numbers RB in tropical cyclones. At least one 400-m layer above z = 7.5 km exhibited RB < 1 in 96% of the sondes and RB ≤ 0.25 in 35% of the sondes. The latter represent almost certain turbulence.
David Vollaro, Patrick Duran, John Molinari   +2 more
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Richardson Number Profiles over the Continental Shelf

Journal of Physical Oceanography, 1983
Abstract The seasonal mid-water thermocline over the continental shelf has been examined with the aid of an oceanographic Richardson Number Probe. The overall Richardson number of this stable layer was found to be 0.9 but within the thermocline, regions of low gradient Richardson number were observed.
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Turbulence in the Stable Boundary Layer at Higher Richardson Numbers

Boundary-Layer Meteorology, 2011
We present some algebraic and numerical simulations of the stable boundary layer. We also discuss the problem of the existence of a critical Richardson number (Ri), beyond which the turbulence is suppressed. We compare the results of a second-order algebraic model with those of a third-order numerical model and, to this purpose, numerical simulations ...
FERRERO, Enrico, Quan LH, Massone D.
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