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Cheng-Nian Xiao and Inanc Senocak

; Mahrt 2014 ; Williams et al. 2017 ). To the best of our knowledge, the impact of multiple stratification mechanisms on the scaling of flow fields and applicability of MOST as theorized in Kitaigorodskii (1988) and Zilitinkevich and Calanca (2000) , i.e., when stratification is not solely an outcome of surface cooling, has not yet been validated by numerical investigations. In the present work, we perform direct numerical simulations (DNS) to study the dynamics of an initially neutral open-channel

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Robert A. Handler, Richard P. Mied, Gloria J. Lindemann, and Thomas E. Evans

1. Introduction Coriolis acceleration plays an important role in geophysical flows because one effect of a rotating reference frame is to couple motions in perpendicular directions. This is particularly significant for channel flows, as was first discussed by Benton (1956) . He showed that fluid flowing in a circular pipe, rotating with rapid constant angular velocity about an axis perpendicular to the flow direction, generates secondary circulations transverse to the flow along the channel

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Greg Wilson and H. Tuba Özkan-Haller

1. Introduction Flow in freshwater channels (rivers and upper estuaries) is governed by a number of factors, including the rate of discharge and the channel geometry. The latter may include effects due to large-scale bedforms, such as bars and holes. Knowledge of bathymetry is therefore essential for modeling the channel hydrodynamics, particularly at the reach scale. In many natural settings, however, it is not practical to obtain a detailed field survey of bathymetry. Various methods have

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Ted Conroy, David A. Sutherland, and David K. Ralston

correlations between the salinity and velocity at tidal time scales can be a substantial component of the salt balance ( Hughes and Rattray 1980 ; Ralston et al. 2010 ; Chen et al. 2012 ). The tidal salt flux is typically characterized as a dispersive process acting on the subtidal along-channel salinity gradient ( Fischer 1976 ). This dispersive transport is independent of the exchange flow due to gravitational circulation, and the relative contribution of the tidal and subtidal components of the salt

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M. C. Gregg and L. J. Pratt

, the bottom along the thalweg is very rough, varying by ±25 m over 1 km or less. After a constriction at 32 km, the channel turns sharply clockwise toward the mouth of Dabob Bay, a small secondary fjord extending northward from the canal. Because of flow separations, stream tube areas may differ from those of the channel, but we lack information to evaluate this, except where we took cross-channel runs. Several rivers flowing down from the Olympics enter the western side of the canal between the

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J. Egger

2232 JOURNAL OF THE ATMOSPHERIC SCIENCES VoL. 52, No. 12Tropopause Height in Baroclinic Channel Flow JOSEPH ECa3ER Meteorologisches Institut, Universitdt Miinchen, Munich, Germany(Manuscript received 1 April 1994, in final form 30 December 1994) A wave-mean flow model of dry channel flow is used to investigate the processes that determine the heightHr and the

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Michel A. J. de Nijs, Julie D. Pietrzak, and Johan C. Winterwerp

. At both stations a net import of salinity occurred. Interestingly, the shape of the residual transport profile at station 1 is what one would expect on the basis of the competition between the freshwater discharge and the classical gravitational circulation driven by the along-channel baroclinic pressure gradient ( Officer 1976 ). The residual transport profile at station 2 most likely is a combination of the competition between the baroclinic pressure-gradient-driven shear flows, asymmetry in

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Christopher C. Chapman and Andrew McC. Hogg

the horizontal grid spacing chosen for this study (5 km) is less than the deformation radius for the choices of Coriolis parameter and stratification (∼10 km), which in our experience permits adequate representation of the effect of eddies on the mean flow. Table 1. Standard parameters for simulations. We use a zonally reentrant channel on a β plane as an analog for the Southern Ocean. Forcing is provided by a zonally invariant westerly wind stress, with a truncated sinusoidal profile in the

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V. O. Ivchenko, V. B. Zalesny, and B. Sinha

). McWilliams et al. (1978) and McWilliams and Chow (1981) demonstrated sharpening of zonal flow by PV mixing in an eddy-resolving quasigeostrophic zonal channel model. It was further demonstrated that using a diffusive parameterization of quasigeostrophic PV (QGPV) in a zonal channel can result in sharper and stronger currents ( Ivchenko 1984 ; Ivchenko et al. 1997 , 2014b ), provided a spatially variable positive diffusion coefficient is specified, with local minima in regions occupied by jets

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Walter Zenk, Gerold Siedler, Bernd Lenz, and Nelson G. Hogg

the Vema Channel (sill depth 4660 m) and near 28°W the Hunter Channel (∼4200 m). They allow the export of Antarctic Bottom Water from the Argentine Basin. Some additional flow of bottom water occurs across the Lower Santos Plateaus between the Continental Rise and the Vema Channel. According to a recent study, however, based on two-year long direct current observations ( Hogg et al. 1998 ), the majority of the water masses there appear to recirculate within the Brazil Basin. Due to their

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