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298

May 6, 2010
05/10

by
Jiusto, J. E

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Fog - radiation, advection and air mass fog - vertical distribution, growth rate and control concept

Topics: ADVECTION, RADIATION, VERTICAL DISTRIBUTION, AIR MASSES, FOG, FOG DISPERSAL, RADIATION, RAINDROPS,...

In this paper, some recent developments in the analysis of the BMO space have been applied to the advection dispersion equation. Then the upper and lower bound have been obtained for the concentration and dispersion coefficient of the advection dispersion equation under the conditions where source term and stirring term of advection dispersion equation belong to BMO space.

Topics: Advection Dispersion Equation, BMO, Dispersion Coefficient

Mendeley Climate Change Library

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41

Jul 6, 2019
07/19

by
Yuan Li; Jianjun Jia; Qingguang Zhu; Peng Cheng; Shu Gao; Ya Ping Wang

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Suspended sediment concentration (SSC) has a significant impact on the estuarine environment and its morphological evolution. At any given location, the temporal variability of depth-averaged SSC is due to a combination of two processes: horizontal advection and local resuspension. In this study, we investigated the sediment dynamics at three anchored monitoring stations close to the maximum turbidity zone of the Changjiang Estuary, and developed a box model to differentiate the effects of...

Topics: Advection, Box model, Changjiang Estuary, Resuspension, Suspended sediment

Mathematical Journal of Interdisciplinary Sciences Vol.7, No.1

Topic: Advection Dispersion Convergence-control parameter Discrete squared residual

Natural decay of pollutants is rarely consider in mass transport equation. This paper develops a mathematical model of a filter based on iron oxide coated sand for the removal of chromium in groundwater and surface water. The natural decay of chromium was analyzed using a zero order decay reaction. The advection dispersion equation for this purpose is solved analytically using the Laplace transform method and numerically by the Fourth order Runge kutta method to determine the spatio-temporal...

Topics: Filter, Sand, Iron oxide, Chromium, Adsorption, advection-dispersion, Laplace.

Potential vorticity and jet streak properties associated with 23 explosive and non-explosive cyclones from the western North Atlantic and western North Pacific Oceans are analyzed for the period 17 January to 23 February 1979. ECMWF analyses with FGGE data are used to represent the 300 mb wind fields over these ocean areas. Relative maxima in potential vorticity are present upstream of all cyclones. Storm tracks with respect to the potential vorticity maxima are counter-clockwise with the...

Topics: Meteorology, potential vorticity, jet streaks, explosive cyclogenesis, vorticity advection

The purpose of this research was to investigate the effect of tidal - period internal wave vertical motion on oceanic mixed layer dynamics, and to discern the effect upon the diurnal evolution of thermoclines, as observed during MILE (mixed layer experiment). Vertical advection was added to a one-dimensional bulk model of the mixed layer with an assumed linear in z and sinusoidal in time dependence. The rate of mixed layer deepening was therefore due to the combination of vertical mction and...

Topics: Oceanography, Mixed layer modelling, vertical advection and mixed layer modelling

668
668

May 28, 2011
05/11

by
Paliwoda, L

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This document contains the procedure and the test results of the Advanced Microwave Sounding Unit-A (AMSU-A) Earth Observing System (EOS) Project, assembly part number 1356008-1, serial number 202, Electromagnetic Interference (EMI) and Electromagnetic Susceptibility (EMC) qualification test. The test was conducted in accordance with the approved EMI/EMC Test Plan/Procedure, Specification number AE-26151/8B, dated 10 September 1998. Aerojet intends that the presentation and submittal of this...

Topics: VORTICITY, ATMOSPHERIC GENERAL CIRCULATION MODELS, LAGRANGIAN FUNCTION, ADVECTION, NONLINEARITY,...

The response of the seasonal thermocline formation and mixing to prescribed vertical interior motion is examined. For the annual and shorter period interior motion cases studied, the response was strongest for the annual period. For an oscillatory vertical motion having a 15 m amplitude at a 75 m depth, warm sea surface temperature anomalies of up to 2.16 C and cold anomalies of up to 2.04 C are found, depending on the phase difference between the interior motion and the annual heat cycle. The...

Topics: Meteorology, mixed layer modelling, vertical advection, long period interior motion

Abstract — A direct simulation investigations of contaminant transport has been conducted. The simulations are based on the unsteady longitudinal advection diffusion contaminant decay equation, which is discretized using finite element Galerkin’s method with backward difference time formulation with the application of COMSOL Multiphysics Software Package. It was observed that the simulation results, which are illustrated pictorially via line graphs and contours, consistently represented the...

Topics: Advection, COMSOL Multiphysics, Contaminant decay, Dispersion, Pollution, Time-dependent sources.

172
172

May 27, 2011
05/11

by
Jewitt, Davi

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The aim of this proposal was to analyse a set of charge-coupled device images of the Jupiter-impacting comet D/Shoemaker-Levy 9. The images were obtained primarily using the University of Hawaii 2.2-m telescope and a standardized imaging device, providing an unusually uniform set of data. Additional data included a set of spectra taken in search of gaseous emission from SL9 using the UH 2.2-m and Keck 10-m telescopes.

Topics: ANNUAL VARIATIONS, CARBON, PARTICULATES, SARGASSO SEA, DIFFUSION, ADVECTION, ESTIMATES, OXYGEN,...

This effort is closely linked with our effort on ONR grant N00014-05-1-0092 and is a component of the Optimal Deployment of Drifting Acoustic Sensors, ODDAS. We collaborate with A. C. Poje of CUNY SI; S. Riedlinger and R. Allard at NRL SSC; D. Hammond at Advanced Avionics; and D. Porter and R. Heitsenrether at APL/JHU. The long-term goal of ODDAS is to develop strategies for the deployment of drifting sensors that maximize the amount of environmental information collected with the fewest...

Topics: DTIC Archive, DELAWARE UNIV NEWARK, *ACOUSTIC DETECTORS, ADVECTION, INSTRUMENTATION, OCEANOGRAPHIC...

146
146

Jun 1, 2011
06/11

by
Fucha, D

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Unduly high diving speeds can be effectively controlled by diving brakes but their employment involves at the same time a number of disagreeable features: namely, rotation of zero lift direction, variation of diviving moment, and, the creation of a potent dead air region.

Topics: SPACE-TIME CE/SE METHOD, BOUNDARY CONDITIONS, FLOW EQUATIONS, ADVECTION, SHOCK TUBES

In this study, a laboratory soil column experiment was carried out for estimating the dispersivity (?) in sandy loam soil by the inversion of the Advection-Dispersion Equation. An 89 cm deep and 15 cm diameter cylindrical column was filled with sandy loam soil in such a way that the bulk density of the soil in field condition was strictly satisfied in the column. Potassium bromide was used as the conservative tracer in the study. The tracer concentration was allowed to pass through the column...

Topics: Dispersivity: Advection Dispersion Equation, Effective dispersion coefficient, Laboratory soil...

Previous experimental investigations have shown that the characteristics of flow about a circular cylinder immersed in a time-dependent flow exhibit cycle-to-cycle variations. These variations have been attributed to the variations in the spanwise coherence, aspect ratio, nonuniformity of the flow, and random disturbances in the ambient flow. A theoretical investigation was undertaken to examine the stability of the flow characteristics in terms of the initial state of the vortices. An...

Topics: Mechanical engineering, vortex advection, chaos, vortices, vortex motion, coherence length, aspect...

A layer-ocean model was developed based on the mixed layer models of Kraus and Turner (1967) and Denman (1972). The ocean model was coupled to Pearson's (1972) time varying, symmetrical-stationary hurricane model which was based on a model proposed by Riehl (1963), and in which the air-sea interaction was specified by Cardone's (1969) extension of Blackadar's (1965) two-layer, baroclinic boundary-layer model. Time-dependent solutions for ocean mixed layer depth and temperature were obtained in...

Topics: Meteorology, air-sea interaction, hurricane model, ocean model, convective mixing, wind mixing,...

In this research paper, we apply the novel Temimi Ansari method to six first order nonlinear partial differential equations for exact solution namely Burger’s equation, Fisher’s equation, Schrodinger equation, wave equation, advection equation and KDV equations respectively. Unlike other semi analytical iterative methods, this method doesn’t require linearization, perturbation, discretization, or the calculation of an Adomian polynomials for nonlinear terms in the Adomian decomposition...

Topics: KDV Equation, Advection equation, Schrödinger equation, Burger’s equation, Fisher’s equation,...

Naval Postgraduate School

22
22

Jan 31, 2021
01/21

by
Clark, Stanley Davis, Sr.; Langemo, James Carroll

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This paper presents a relatively simple method for producing a 24-hour prognostic 500-mb chart by graphical means. It modifies the Fjortoft graphical method by incorporating a technique to include the intensification and weakening of systems. That is, is uses factors which allow intensification of poleward-moving cyclones and weakening of equatorward-moving cyclones and the converse for anticyclones. The theoretical development of the so-called \"geostrophic model\" used, the research...

Topics: Meteorology, Prognostic, 500 mb, Graphical, Modification of Fjortoft, Intensity change, Relative...

266
266

May 27, 2011
05/11

by
Schneider, Harol

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This method is investigated for semi-infinite multiple-slab configurations of arbitrary width, composition, and source distribution. Isotropic scattering in the laboratory system is assumed. Isotropic scattering implies that the fraction of neutrons scattered in the i(sup th) volume element or subregion that will make their next collision in the j(sup th) volume element or subregion is the same for all collisions. These so-called ''transfer probabilities'' between subregions are calculated and...

Topics: BOLTZMANN TRANSPORT EQUATION, HYDRODYNAMICS, MODELS, NAVIER-STOKES EQUATION, NONLINEARITY,...

270
270

May 31, 2011
05/11

by
Otterman, J.; Walczewski, J., et al; Ardizzone, J.; Atlas, R.; Bungato, D.; Cierniewski, J.; Jusem, J. C.; Przybylak, R.; Schubert, S.; Starr, D.

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The aim of this paper is to report extreme winter/early-spring air temperature (hereinafter temperature) anomalies in mid-latitude Europe, and to discuss the underlying forcing to these interannual fluctuations. Warm advection from the North Atlantic in late winter controls the surface-air temperature, as indicated by the substantial correlation between the speed of the surface southwesterlies over the eastern North Atlantic (quantified by a specific Index Ina) and the 2-meter level air...

Topics: COMPUTATIONAL FLUID DYNAMICS, TEXTURES, THREE DIMENSIONAL MODELS, FLOW VISUALIZATION, FLOW...

Abstract — Stochastic advection diffusion equation (SADE) with multiplicative stochastic input is a practical mathematical model for different physical phenomena. In this paper, SADE will be studied using two spectral stochastic techniques. The first is the Wiener chaos expansion (WCE) technique and the second is the Wiener-Hermite expansion with perturbation (WHEP) technique. These techniques convert the SADE into a system of deterministic partial differential equation (DPDE) that can be...

Topics: Advection diffusion equation, Multiplicative random input, Wiener-Hermite expansion, Wiener-Chaos...

In this section we define a measure of mixing that does not necessarily require diffusion to measure the amount of homogenization that occurs during the mixing process.

Topics: DTIC Archive, WOODS HOLE OCEANOGRAPHIC INSTITUTION MA, *FLUID DYNAMICS, ADVECTION, DIFFUSION,...

High surface winds over California and the bordering Pacific Ocean resulted in the death of one man and the loss of power to approximately 50,000 residences across the state. These damaging winds are hypothesized to result from an upper level front and associated tropopause folding that rapidly intensify as they move south across the region, causing high momentum air to be transported to the lower troposphere. Once the high momentum air reaches the top of the planetary boundary layer, the...

Topics: Tropopause, Upper-level frontogenesis, Tropopause folding, Jet-streak, Cold-air advection, Shear,...

We have two major goals. The first is to improve our capabilities and scientific knowledge concerning Lagrangian predictability in the ocean. Specific applications include search and rescue operations, the design of float and drifter experiments, and the understanding of stirring mechanisms. The second goal is to develop methods allowing the assessment of the underlying dynamics and predictability of complex physical systems in the ocean based solely on the analysis of time-series.

Topics: DTIC Archive, WOODS HOLE OCEANOGRAPHIC INSTITUTION MA, *OCEANS, *PREDICTIONS, *WATER FLOW,...

258
258

Jun 9, 2011
06/11

by
Carle, Alan; Fagan, Mike; Green, Lawrence L

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This report describes preliminary results obtained using an automated adjoint code generator for Fortran to augment a widely-used computational fluid dynamics flow solver to compute derivatives. These preliminary results with this augmented code suggest that, even in its infancy, the automated adjoint code generator can accurately and efficiently deliver derivatives for use in transonic Euler-based aerodynamic shape optimization problems with hundreds to thousands of independent design...

Topics: DIFFUSION, TRIANGULATION, UPWIND SCHEMES (MATHEMATICS), FINITE VOLUME METHOD, ADVECTION,...

The cross-shore exchange of material is examined on beaches of varying morphology and hydrodynamics. On a dissipative, rip-channeled beach in Monterey, California, field measurements of the rip current vertical structure reveal depth-uniform flows inside the surf zone, and surface-dominated flows with rotation over depth outside the surf zone. Aperiodic, very low frequency pulsations in the near-surface velocity were found to control the mean rip current flow. Observations of Lagrangian surface...

Topics: Eulerian, Lagrangian, advection, diffusion, dispersion, drifters, dye, mixing, rip current, steep...

This is part of a collaborative program Optimal Deployment of Drifting Acoustic Sensors, ODDAS, which involves academic, private sector, and Navy scientists. The long-term goal of ODDAS is to develop strategies for the deployment of drifting sensors that maximize the amount of environmental information collected with the fewest sensors. The primary long-term goal of our component is to quantify oceanic submesoscale stirring and advective transport processes and to assess their roles in the...

Topics: DTIC Archive, DELAWARE UNIV NEWARK COLL OF MARINE AND EARTH STUDIES, *ACOUSTIC DETECTORS,...

In response to Air Weather Service requirements, the Air Force Geophysics Lab has been involved in research in the development of mesoscale advection fog prediction techniques. A two-dimensional fog prediction model developed at the Naval Environmental Prediction Research Facility (NEPRF) was selected for evaluation because it can operate on a mini-computer of the size planned for the Air Force's Automated Weather Distribution System (AWDS). Six case studies developed by Calspan Advanced...

Topics: DTIC Archive, Weyman,J, AIR FORCE GEOPHYSICS LAB HANSCOM AFB MA, *FOG, MATHEMATICAL MODELS,...

In this paper, spatially high-order Residual-Distribution (RD) schemes using the first-order hyperbolic system method are proposed for general time-dependent advection-diffusion problems. The corresponding second-order time-dependent hyperbolic advection-diffusion scheme was first introduced in [NASA/TM-2014-218175, 2014], where rapid convergences over each physical time step, with typically less than five Newton iterations, were shown. In that method, the time-dependent hyperbolic...

Topics: DTIC Archive, NATIONAL INST OF AEROSPACE ASSOCIATES HAMPTON VA, *ADVECTION, *DIFFUSION, *TIME...

One major issue in the accurate solution of convection-dominated problems by means of high-order methods is the ability of the solver to maintain monotonicity. This problem is critical for spectral elements, where Gibbs oscillations may pollute the solution. However, typical filter-based stabilization techniques used with spectral elements are not monotone. In this paper, residual-based stabilization methods originally derived for finite elements are constructed and applied to high-order...

Topics: DTIC Archive, NAVAL POSTGRADUATE SCHOOL MONTEREY CA DEPT OF APPLIED MATHEMATICS, *COMPUTATION...

The time dependent mixed-layer depth and temperature response of a two-layer hydrothermodynamic ocean model to a moving hurricane model was investigated. The hurricane model was that of Elsberry, Pearson, and Corgnati (1974). The maximum eye radius and hurricane intensity was bounded to isolate ocean reaction from hurricane variance. The ocean model was based on the upwelling model of O'Brien and Hurlburt (1972) in two dimensions and was located along the path of the storm. The momentum and...

Topics: Meteorology, Air-Sea Interaction, Hurricane Model, Ocean Model, Convective Mixing, Wind Mixing,...

The 1D PBL model has been substantially improved to incorporate vertical motion from GEMPAK grid files, so that vertical advection (subsidence) realistically affects PBL growth. The stable growth has been refined to ensure correct matching under PBL transitions from one regime to another.

Topics: DTIC Archive, Ruscher, Paul, FLORIDA STATE UNIV TALLAHASSEE DEPT OFMETEOROLOGY, *BOUNDARY LAYER,...

A velocity field. even one that represents a steady state flow implies a dynamical system. Animated velocity fields is an important tool in understanding such complex phenomena. This paper looks at a number of techniques that animate velocity fields and propose two new alternatives, These are texture advection and streamline cycling. The common theme among these techniques is the use of advection on some texture to generate a realistic animation of the velocity field. Texture synthesis and...

Topics: NASA Technical Reports Server (NTRS), VELOCITY DISTRIBUTION, ADVECTION, EQUILIBRIUM FLOW, CYCLES,...

This research presents a novel high-order space-time method for hyperbolic conservation laws. Two important concepts, the staggered space-time mesh of the space-time conservation element/solution element (CE/SE) method and the local discontinuous basis functions of the space-time discontinuous Galerkin (DG) finite element method, are the two key ingredients of the new scheme. The staggered space-time mesh is constructed using the cell-vertex structure of the underlying spatial mesh. The...

Topics: DTIC Archive, JACKSON STATE UNIV MS DEPT OF COMPUTER ENGINEERING, *DIFFERENTIAL GEOMETRY,...

The goal of this report is to understand the convective process in the ocean, develop numerical models to study it, and so improve the representation of convection in ocean circulation models. To understand the relative importance of vertical mixing by convection and lateral advection by geostrophic eddies in setting the volume and properties of water-masses formed by intense winter storms blowing over the open ocean. The insights gained will inform and improve parametric representations of...

Topics: DTIC Archive, MASSACHUSETTS INST OF TECH CAMBRIDGE, *CONVECTION, *OCEAN MODELS, ADVECTION, MIXING,...

The work of Davis which imports the concept of total variation diminution (TVD) into non-upwinded, Lax-Wendroff type schemes is reformulated in a way which is easier to analyze. The analysis reveals a class of TVD schemes not observed by Davis. Only the case of one dimensional linear advection is treated.

Topics: NASA Technical Reports Server (NTRS), ADVECTION, ALGORITHMS, TVD SCHEMES, FINITE DIFFERENCE THEORY,...

Our ultimate goal is to understand the dynamics of strong, narrow ocean currents that persist for hundreds or thousands of kilometers, despite being in contact with the (frictional) bottom. Our immediate objective is to understand how vertical mixing and advection within the bottom boundary layer influence the three-dimensional structure, evolution, and dynamics of both the bottom boundary layer and the overlying (interior) flow.

Topics: DTIC Archive, WOODS HOLE OCEANOGRAPHIC INSTITUTION MA, *OCEAN CURRENTS, ADVECTION, BOUNDARY LAYER,...

Two-dimensional simulations of the 11 January 1972 Boulder, Colorado, windstorm, obtained from 11 diverse nonhydrostatic models, are intercompared with special emphasis on the turbulent breakdown of topographically forced gravity waves, as part of the preparation for the Mesoscale Alpine Programme field phase. The sounding used to initialize the models is more representative of the actual lower stratosphere than those applied in previous simulations. Upper-level breaking is predicted by all...

Topics: DTIC Archive, NAVAL RESEARCH LAB MONTEREY CA, *GRAVITY WAVES, *STORMS, WIND, DISSIPATION,...

Marine fog forecasts during the summer period in the North Pacific are not made with any acceptable degree of accuracy. Objective fog development models exist and are used with some success for localized coastal regions of the western U.S.; scarcity of accurate data has hindered creation of a reliable open-ocean model. The Eulerian single-station approach, utilizing a segment of the complete accurate data of Ocean Weather Station Papa (50N,145W) is applied in the study to an objective marine...

Topics: Oceanography, Advection fog, Fog forecasting, Marine fog, North Pacific Ocean fog, Open-ocean fog,...

The core motivating ideas of the space-time CESE method are clearly presented and critically analyzed. It is explained why these ideas result in all the simplifying and enabling features of the CESE method. A thorough discussion of the a scheme, a two-level non-dissipative CESE solver of a simple advection equation with two independent mesh variables and two equations per mesh point is also presented. It is shown that the scheme possesses some rather intriguing properties such as: (i) its two...

Topics: NASA Technical Reports Server (NTRS), INVARIANCE, DISSIPATION, SIMPLIFICATION, TIME, SPACE,...

In this lecture we shall focus on the dynamics of individual phytoplankton cells and on simple models to describe their motion in the fluid flow. Phytoplankton cells are small with dimensions up to a few hundred microns. Individual phytoplankton cells immersed in water are advected by the surrounding flow, even though some species can resist passive advection by various means, such as varying their buoyancy and/or swimming. In addition most plankton cells are slightly heavier than water and are...

Topics: DTIC Archive, WOODS HOLE OCEANOGRAPHIC INSTITUTION MA, *PHYTOPLANKTON, ADVECTION, BUOYANCY, CELLS,...

This technical note discusses three advection patterns favorable for freezing precipitation. Two graphs were developed based on 503 freezing precipitation occurrences during the past 11 years- a 1000- to 500-mb thickness graph and an 850-mb temperature graph. Two anticyclonic pressure patterns are discussed throughout the technical note. Relationships between inverted troughs and 850-mb lows are presented. Considerable discussion on synoptic patterns across the continental United States is...

Topics: DTIC Archive, Weber, Eugene M., AIR FORCE WEATHER AGENCY OFFUTT AFB NE, *SYNOPTIC METEOROLOGY,...

The funded period of this project ran out on 30 November 2007; a no-cost extension of 3 months was requested by the PI for medical reasons, and was granted. In the second year the effort addressed the following issues: (1) making the Recovery-based Discontinuous Galerkin method (RDG) suitable for multidimensional applications, (2) increasing its efficiency by constructing the recovery basis once as pre-processing step for an entire calculation, (3) the combination of RDG with upwind DG for...

Topics: DTIC Archive, van Leer, Bram, MICHIGAN UNIV ANN ARBOR, *DIFFUSION, *DISCONTINUITIES, *GALERKIN...

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As proposed in the above OAI/NASA Glenn Research Center (GRC) Co-Operative Agreement the objective of the work was to provide consultation and assistance to the NASA GRC GTX Rocket Based Combined Cycle (RBCC) Program Team in planning and developing requirements, scale model concepts, and plans for an experimental nozzle research program. The GTX was one of the launch vehicle concepts being studied as a possible future replacement for the aging NASA Space Shuttle, and was one RBCC element in the...

Topics: TRANSPORT THEORY, TIME DEPENDENCE, WALL FLOW, COMPUTATIONAL FLUID DYNAMICS, HAMILTON-JACOBI...

In this lecture we will try to understand local or Lagrangian theories involved in mixing of passive scalars. This involves solving the advection-diffusion (AD) equation along fluid trajectories. The origins of these local theories can be traced to Batchelor's idea of describing the flow via spatially-constant strain-rate matrices with prescribed time dependence. Kraichnan addressed the problem next by considering the velocity field in the AD equation to be a stochastic Gaussian field with a...

Topics: DTIC Archive, WOODS HOLE OCEANOGRAPHIC INSTITUTION MA, *FLUID MECHANICS, *MIXING, ADVECTION,...

The long-term goal is to improve our capabilities and scientific knowledge concerning Lagrangian predictability in the ocean. Specific applications include search and rescue operations, the design of float and drifter experiments, and the understanding of stirring mechanisms. The objectives are: 1) To identify robust geometrical structures that help distinguish regions of inherent unpredictability (Lagrangian chaos) from predictable (regular) regions. 2) Also, to identify geographical regions...

Topics: DTIC Archive, WOODS HOLE OCEANOGRAPHIC INSTITUTION MA, *COMPUTATIONAL FLUID DYNAMICS, *OCEAN...

210
210

Jun 17, 2010
06/10

by
Pogosyan, Kh. P

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Tropospheric influence on temperature fields, circulation, and convection currents in stratosphere

Topics: ADVECTION, STRATOSPHERE, TEMPERATURE FIELD, TROPOSPHERE, ATMOSPHERIC CIRCULATION, ATMOSPHERIC...

For advection schemes based on fluctuation splitting, a design criterion of optimizing the time step leads to linear schemes that coincide with those designed for least truncation error. A further stage of optimizing the time step using a nonlinear positivity criterion, leads to considerable further gains in resolution.

Topics: NASA Technical Reports Server (NTRS), ADVECTION, COMPUTATIONAL GRIDS, NONLINEARITY, THEOREM...

Hybrid Eulerian-Lagrangian semi-implicit time-integrators (HELSI) are presented which use the standard semi-implicit formulation as their starting point. The advantage of such an approach is that existing models which employ Eulerian semi-implicit time-integrators can easily be augmented to use the HELSI approach, that is, provided that either: a series of advection problems can be solved efficiently as in the operator-integration-factor splitting (OIFS) method or that the grid and underlying...

Topics: DTIC Archive, NAVAL RESEARCH LAB MONTEREY CA, *LAGRANGIAN FUNCTIONS, *EULER EQUATIONS,...

An advective mixed layer ocean model was developed by eliminating the assumption of horizontal homogeneity in an already existing mixed layer model, and then superimposing a mean and anomalous wind driven current field. This model is based on the principle of conservation of heat and mechanical energy and utilizes a box grid for the advective part of the calculation. Three phases of experiments were conducted: evaluation of the model's ability to account for climatological sea surface...

Topics: NASA Technical Reports Server (NTRS), ADVECTION, MATHEMATICAL MODELS, PREDICTIONS, SEAS, SURFACE...