Relevant bibliographies by topics / Menter Shear stress transport

Academic literature on the topic 'Menter Shear stress transport'

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Published: 10 December 2022
Last updated: 28 January 2023

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Journal articles on the topic "Menter Shear stress transport"

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Philipbar, Brad M., Jiajia Waters, and David B. Carrington. "A finite element Menter Shear Stress turbulence transport model." Numerical Heat Transfer, Part A: Applications 77, no. 12 (April 20, 2020): 981–97. http://dx.doi.org/10.1080/10407782.2020.1746155.

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Huang, Junji, Jorge-Valentino Bretzke, and Lian Duan. "Assessment of Turbulence Models in a Hypersonic Cold-Wall Turbulent Boundary Layer." Fluids 4, no. 1 (February 26, 2019): 37. http://dx.doi.org/10.3390/fluids4010037.

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In this study, the ability of standard one- or two-equation turbulence models to predict mean and turbulence profiles, the Reynolds stress, and the turbulent heat flux in hypersonic cold-wall boundary-layer applications is investigated. The turbulence models under investigation include the one-equation model of Spalart–Allmaras, the baseline k - ω model by Menter, as well as the shear-stress transport k - ω model by Menter. Reynolds-Averaged Navier-Stokes (RANS) simulations with the different turbulence models are conducted for a flat-plate, zero-pressure-gradient turbulent boundary layer with a nominal free-stream Mach number of 8 and wall-to-recovery temperature ratio of 0.48 , and the RANS results are compared with those of direct numerical simulations (DNS) under similar conditions. The study shows that the selected eddy-viscosity turbulence models, in combination with a constant Prandtl number model for turbulent heat flux, give good predictions of the skin friction, wall heat flux, and boundary-layer mean profiles. The Boussinesq assumption leads to essentially correct predictions of the Reynolds shear stress, but gives wrong predictions of the Reynolds normal stresses. The constant Prandtl number model gives an adequate prediction of the normal turbulent heat flux, while it fails to predict transverse turbulent heat fluxes. The discrepancy in model predictions among the three eddy-viscosity models under investigation is small.
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Zheng, Qiu Ya, and San Yang Liu. "Drag Prediction on DLR-F6 Wing-Body Configuration." Applied Mechanics and Materials 110-116 (October 2011): 1506–11. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.1506.

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This paper mainly investigate the accuracy of the computed drag on the DLR-F6 Wing-Body configuration, and analyze effect of grid and the turbulence models including the Spalart-Allmaras model, Wilcox’s k-ω model and Menter shear-stress transport model on aerodynamic forces for wing-body configuration. The computed results show that grid refinement has little effect on the pressure distributions, significant effect on drag. The turbulence models have certain effects on the pressure distributions, especially positions of the shock wave. They have obvious effects on drag, particularly friction drag. This study shows that performing the CFD calculation at the same angle-of-attack as experiment resulted in good comparisons with wing surface pressures.
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Sun, M. B., J. H. Liang, and Z. G. Wang. "A modified blending function for zonal hybrid Reynolds-averaged Navier—Stokes/large-eddy simulation methodology." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 223, no. 8 (August 1, 2009): 1067–81. http://dx.doi.org/10.1243/09544100jaero575.

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A modified blending function for zonal hybrid Reynolds averaged Navier—Stokes/large eddy simulation (RANS/LES) methodology was developed using an empirical analogy from Menter k—ω shear stress transport (SST) turbulent model (Menter, 1994) to predict complex turbulent flows. Tests of slot jet in supersonic flow and supersonic flow over compression—expansion ramp was conducted and prediction of separations was well improved when certain model constant was forced on the traditional blending function (Baurle et al., 2003). Analysis based on calculations of flat plate boundary layer demonstrated that an efficient empirical constant could be used in blending function and boundary layer could be well calculated without heavy contamination of RANS on wake region. Validation of the modified zonal hybrid RANS/LES approach for slot jet in supersonic flow, supersonic flow over compression—expansion ramp, supersonic flow over backward facing step, and supersonic cavity flow was conducted. The simulated results showed that the modified blending function performs well on complex turbulent flows. Deficiencies of traditional hybrid zonal RANS/LES method in over-prediction of separations associated with adverse pressure gradient flows were favourably improved.
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Araya, Guillermo. "Turbulence Model Assessment in Compressible Flows around Complex Geometries with Unstructured Grids." Fluids 4, no. 2 (April 28, 2019): 81. http://dx.doi.org/10.3390/fluids4020081.

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One of the key factors in simulating realistic wall-bounded flows at high Reynolds numbers is the selection of an appropriate turbulence model for the steady Reynolds Averaged Navier–Stokes equations (RANS) equations. In this investigation, the performance of several turbulence models was explored for the simulation of steady, compressible, turbulent flow on complex geometries (concave and convex surface curvatures) and unstructured grids. The turbulence models considered were the Spalart–Allmaras model, the Wilcox k- ω model and the Menter shear stress transport (SST) model. The FLITE3D flow solver was employed, which utilizes a stabilized finite volume method with discontinuity capturing. A numerical benchmarking of the different models was performed for classical Computational Fluid Dynamic (CFD) cases, such as supersonic flow over an isothermal flat plate, transonic flow over the RAE2822 airfoil, the ONERA M6 wing and a generic F15 aircraft configuration. Validation was performed by means of available experimental data from the literature as well as high spatial/temporal resolution Direct Numerical Simulation (DNS). For attached or mildly separated flows, the performance of all turbulence models was consistent. However, the contrary was observed in separated flows with recirculation zones. Particularly, the Menter SST model showed the best compromise between accurately describing the physics of the flow and numerical stability.
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Islam, Saad, and Md Shafiqul Islam. "Numerical Analysis for Determination of Hydrodynamic Characteristics of a Gimbaled Thrust Vectoring Nozzle." Journal of Bangladesh Academy of Sciences 41, no. 1 (August 23, 2017): 69–84. http://dx.doi.org/10.3329/jbas.v41i1.33505.

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Gimbaled thrust vectoring nozzles are employed in Solid Rocket Motors (SRM) to account for the aspects of maneuverability of the flight vehicle. The flow field of such a solid pulsed rocket motor is explored numerically (from dome-closeout onward) by solving Reynolds-averaged Navier-Stokes equations with Menter’s Shear Stress Transport (SST) k - ? turbulence model using a Computational Fluid Dynamics (CFD) tool. Parametric studies are carried out to find out the thermochemical and hydrodynamic characteristics of the hot gas in the rocket motor nozzle. The performances of different supersonic and subsonic sections were studied in terms of the hydrodynamic aspects such as static pressure and Mach number distribution. It is observed that the tradeoff of implementing thrust vectoring mechanism amounts to an additional pressure loss of 10.06% in the rocket motor. Such analyses are specific to certain types of Short Range Ballistic Missiles (SRBM) having solid state propellant (primary stage) in radial boost, end burning pulsed configuration with exacting demands on maneuverability and control implied upon payload and mission criterion.Journal of Bangladesh Academy of Sciences, Vol. 41, No. 1, 69-84, 2017
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Lobanov, I. E. "MATHEMATICAL LOW-REYNOLDS MODELING OF HEAT EXCHANGE IIN TURBULENT FLOW IN FLAT CHANNELS WITH TURBULATORS SYMMETRICALLY LOCATED ON BOTH SIDES." Herald of Dagestan State Technical University. Technical Sciences 45, no. 2 (December 17, 2018): 70–93. http://dx.doi.org/10.21822/2073-6185-2018-45-2-70-93.

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ObjectivesThe aim of the study was to simulate the heat transfer in flat channel with turbulators, symmetrically located on its both sides, depending on the channel's geometric parameters and the coolant flow modes followed by the verification of the obtained calculated data by the existing experiment.MethodsThe calculation was carried out on the basis of a theoretical method based on the solution of the Reynolds equations, closed with the help of the Menter shear stress transport model, by factored finite-volume method, as well as the energy equation on multiscale intersecting structured grids (Fast COmposite Mesh method, FCOM).ResultsA theoretical mathematical calculation model for intensified heat exchange in turbulent flow for a flat channel with turbulators, symmetrically located on both sides, depending on the channel's geometric parameters and coolant flow modes was generated. The calculation results of the intensified heat exchange in flat channels with double turbulators, depending on the determining parameters, are in very good agreement with the existing experimental material and have an undeniable advantage over the latter, since the assumptions made in their derivation cover a much wider range of determining parameters than the limitations of the experiments (Pr = 0.7 ч 100; Re = 103ч 106; h / dЭ= 0.005 ч 0.2; t / h= 1 ч 200). ConclusionAccording to the calculation results based on the developed model, it is possible to optimise the heat exchange intensification in flat channels with double turbulators, as well as to control the process of heat exchange intensification. The comparative calculations of the intensified hydraulic resistance and heat exchange for flat channels with two-sided symmetrical flow turbulators with corresponding data for round channels with turbulators were carried out and analysed. From the point of view of heat exchange intensification, all other conditions being equal, the reduction of a flat channel with two-sided symmetrical turbulators with respect to a round tube with turbulators takes place because a smaller increase in heat exchange is achieved with a greater increase in hydraulic resistance. It was established by calculation that the relative hydraulic resistance ξП/ ξT for channels with turbulators is always higher than for smooth channels; however, the relative heat exchange NuП/ NuT for channels with turbulators can be higher than for smooth channels. Therefore, there is an enhanced redistribution of the temperature drop over the channel section with an intensified heat exchanger. The developed theoretical method based on the solution of the Reynolds equations by the factored finite-volume method, combined with the energy equation on multiscale intersecting structured grids and closed by means of the Menter shear stress transport model, makes it possible, with reasonable accuracy, to calculate heat exchange coefficients and hydraulic resistance in flat channels of practically any forms of double symmetrically located flow turbulators.
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Bekhit, Adham, and Florin Popescu. "URANSE-Based Numerical Prediction for the Free Roll Decay of the DTMB Ship Model." Journal of Marine Science and Engineering 9, no. 5 (April 21, 2021): 452. http://dx.doi.org/10.3390/jmse9050452.

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In the present study, Computational Fluid Dynamics (CFD) is used to investigate the roll decay of the benchmark surface combatant DTMB-5512 ship model appended with bilge keels, sailing in calm water at different speeds (Fr = 0.0, 0.138, 0.2, 0.28 and 0.41) and with different initial roll angles. The numerical simulations are carried out using the viscous flow solver ISIS-CFD of the FINETM/Marine software provided by NUMECA. The solver uses the finite volume method to build the spatial discretization of the transport equation to solve the unsteady Reynolds-Averaged Navier–Stokes equations. Two-phase flow approach is applied to model the air–water interface, where the free surface is captured using the volume of fluid method. The closure to turbulence is achieved by making use of the blended Menter shear stress transport and the explicit algebraic Reynolds stress models. First, a systematic validation against the experimental data at medium speed and initial roll angle of 10° are performed; then, the effect of the initial roll angle and ship speed is later studied. Numerical errors and uncertainties are assessed using grid and time step convergence study based on Richardson Extrapolation method. A special focus on the flow in the vicinity of the bilge keels during the simulation is also investigated and presented in the form of velocity contours and vortical structure formations. The resemblance between the CFD results and experimental data for roll motion and flow characteristics are within a satisfactory congruence; however, some discrepancies are recorded for the over predicted roll amplitudes in the second and, sometimes, the third roll cycle, which appeared mostly in the cases with high initial roll angles.
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Matvienko, O. V., V. A. Arkhipov, and N. N. Zolotorev. "AERODYNAMICS OF A TURBULENT FLOW IN A ROTATING SEMI-CLOSED CYLINDER." Vestnik Tomskogo gosudarstvennogo universiteta. Matematika i mekhanika, no. 69 (2021): 114–26. http://dx.doi.org/10.17223/19988621/69/9.

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The mathematical model and results of a numerical study of swirling turbulent air flow characteristics in a semi-closed cylinder rotating around a symmetry axis are presented. A physical and mathematical model is used to describe aerodynamics of the stationary isothermal axisymmetric swirling flow, which includes the Navier-Stokes equations in cylindrical coordinates. The study of turbulence characteristics is carried out using the composite model Menter SST (Shear Stress Transport). The numerical solution is obtained using a chess grid. Nodes for axial and radial velocity components are located in the middle of the control volume faces for scalar quantities. Calculations are performed on a grid with 2000 and 1700 nodes in the axial and radial directions, respectively. The grid refinement is performed near the walls and in the areas with large velocity gradients. The calculated results show that the main grid refinement by 2 times in the axial and radial coordinates leads to a change in the values of the main variables by less than 1%. It is shown that the flow structure is determined by the rotational speed and cylinder height. Analyzing the calculated results, the ratio of the cylinder height to the angular velocity of the cylinder rotation is obtained, which ensures the formation of a quasi-solid rotation zone in the near-edge region.
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Ledezma, G. A., A. Folch, S. N. Bhatia, U. J. Balis, M. L. Yarmush, and M. Toner. "Numerical Model of Fluid Flow and Oxygen Transport in a Radial-Flow Microchannel Containing Hepatocytes." Journal of Biomechanical Engineering 121, no. 1 (February 1, 1999): 58–64. http://dx.doi.org/10.1115/1.2798043.

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The incorporation of monolayers of cultured hepatocytes into an extracorporeal perfusion system has become a promising approach for the development of a temporary bioartificial liver (BAL) support system. In this paper we present a numerical investigation of the oxygen tension, shear stress, and pressure drop in a bioreactor for a BAL composed of plasma-perfused chambers containing monolayers of porcine hepatocytes. The chambers consist of microfabricated parallel disks with center-to-edge radial flow. The oxygen uptake rate (OUR), measured in vitro for porcine hepatocytes, was curve-fitted using Michaelis–Menten kinetics for simulation of the oxygen concentration profile. The effect of different parameters that may influence the oxygen transport inside the chambers, such as the plasma flow rate, the chamber height, the initial oxygen tension in the perfused plasma, the OUR, and Km was investigated. We found that both the plasma flow rate and the initial oxygen tension may have an important effect upon oxygen transport. Increasing the flow rate and/or the inlet oxygen tension resulted in improved oxygen transport to cells in the radial-flow microchannels, and allowed significantly greater diameter reactor without oxygen limitation to the hepatocytes. In the range investigated in this paper (10 μm < H < 100 μm), and for a constant plasma flow rate, the chamber height, H, had a negligible effect on the oxygen transport to hepatocytes. On the contrary, it strongly affected the mechanical stress on the cells that is also crucial for the successful design of the BAL reactors. A twofold decrease in chamber height from 50 to 25 μm produced approximately a fivefold increase in maximal shear stress at the inlet of the reactor from 2 to 10 dyn/cm2. Further decrease in chamber height resulted in shear stress values that are physiologically unrealistic. Therefore, the channel height needs to be carefully chosen in a BAL design to avoid deleterious hydrodynamic effects on hepatocytes.
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Dissertations / Theses on the topic "Menter Shear stress transport"

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Waliszewski, Matthias Werner. "Relationship between in vitro shear stress exposure and transendothelial transport /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487864986610768.

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Mineault-Guitard, Alexandre. "Validation of Observed Bedload Transport Pathways Using Morphodynamic Modelling." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34587.

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Braiding is a mesmerizing phenomenon since flow and sediment transport interact and are able to change the morphology of a channel in a rapid and complex fashion. Conventional two-dimensional morphodynamic models estimate bedload distribution using shear stress distribution. However, it is unclear if the use of such shear stress distributions is relevant or applicable for all situations when using two-dimensional morphodynamic modelling. This thesis strives to investigate whether shear stress distributions are useful to predict bedload transport pathways. This study focuses upon prediction of bedload transport pathways using a morphodynamic model (Delft3D) of an anabranch of the Rees River (New Zealand). Observed bedload transport pathways were compared to modelled bedload transport pathways in an attempt to validate the predictive ability of the model. Results show that there is a significant correlation between predicted bedload transport pathways and the apparent bedload transport pathways derived from the field measurements. Furthermore, bedload transport predictions were in good agreement with observed data in areas where the model’s predictions of high shear stress were comparable to field observations. However, substantial bedload transport predictions in low shear stress areas were not adequately captured by the model, suggesting that the observed pathways were not due to high shear stress, but rather to other sediment supply sources.
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Hong, Dihui Barbee Kenneth A. Jaron Dov. "Role of transport dependent calcium signaling in nitric oxide production and endothelial shear stress responses /." Philadelphia, Pa. : Drexel University, 2007. http://hdl.handle.net/1860/1790.

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Wang, Yung-Chieh (Becky). "Effects of physical properties and rheological characteristics on critical shear stress of fine sediments." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/51723.

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During high flow rates, the acceleration of flow and turbulence around bridge foundations lead to scouring, defined as the removal of bed sediments. Due to the interparticle physico-chemical forces of clay particles, erodibility and transport mechanisms for fine sediments are different from those for coarse sediments, and the capability to predict the erosion resistance of fine sediments is still in question. In this study, silt-clay soil mixtures with different kaolin contents were prepared by mixing ground silica and Georgia kaolin with tap water. Geotechnical tests were carried out to obtain the physical properties of the specimens. The critical shear stress and yield stress of the soil mixtures were determined through hydraulic flume experiments and rheometer tests, respectively. Particle associations of the soil specimens were observed using the technique of scanning electron microscopy (SEM). From the laboratory work and data analysis, relationships among the critical shear stress, yield stress, and the soil physical properties were developed from multiple regression analysis. Specifically, values of the critical shear stress, yield stress, and their dimensionless form can be predicted by the soil properties including bulk density, clay content, and water content. Finally, a single relationship is obtained to predict the Shields parameter as a function of the corresponding dimensionless yield stress in this study. The results can be used to provide a methodology for engineering applications requiring the value of critical shear stress such as estimating fine sediment bed stability and assessing the erosion risk of river beds in proximity to bridge foundations and other flow obstructions.
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Sime, Louise C. "Reach-scale spatial variation of grain-size, shear stress, and bedload transport in gravel-bed rivers." Thesis, University of Sheffield, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401128.

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Valentine, Kendall. "Characterization of the bed, critical boundary shear stress, roughness, and bedload transport in the Connecticut River Estuary." Thesis, Boston College, 2015. http://hdl.handle.net/2345/bc-ir:104550.

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Thesis advisor: Gail C. Kineke
This study characterizes the bed of the Connecticut River estuary in terms of grain size and bedforms, and relates these to river discharge, tidal currents, and sediment transport. Over four field excursions, sediment cores were collected, in addition to bathymetry surveys, and water column measurements. A three-dimensional circulation and sediment transport model calculated boundary shear stress over the same time. The bed of the estuary is composed mostly of sand, with small amounts of fine sediments. Deposition of fine sediments is limited by the landward extent of the salt intrusion. Large bedforms are oriented seaward. The critical shear stress for the median grain size is exceeded each tidal cycle. Bedload transport is dominantly seaward during high discharge conditions, but varies during low discharge. Bathymetry surveys from previous studies and this study show consistent bedform fields over 25 years. Bedforms observed in the field reflect typical conditions rather than extreme events
Thesis (MS) — Boston College, 2015
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Earth and Environmental Sciences
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Koyama, Tomofumi. "Stress, Flow and Particle Transport in Rock Fractures." Doctoral thesis, Stockholm : Mark- och vattenteknik, Kungliga Tekniska högskolan, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4485.

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Koyama, Tomofumi. "Numerical modelling of fluid flow and particle transport in rough rock fracture during shear." Licentiate thesis, Stockholm : Mark och vatten, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-512.

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Perret, Emeline. "Transport of moderately sorted gravels at low bed shear stress : impact of bed arrangement and fine sediment infiltration." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1223/document.

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Le but de cette thèse est de comprendre la dynamique des graviers au sein des rivières alpines à faible contrainte en utilisant des expériences en laboratoire. Ces rivières sont souvent composées d’une large gamme de sédiments, allant des argiles aux galets. Ces différentes classes sédimentaires peuvent interagir entre elles, ce qui peut rendre difficile l’estimation du transport solide. Des expériences en laboratoire ont été conduites en écoulements instationnaires dans un canal de 18m de long et 1m de large. Deux types de lits ont été étudiés : lits unimodaux et bimodaux. Une attention particulière a été portée sur la réalisation des lits de graviers dans notre canal. Ils ont été créés dans le but d’approcher au mieux la configuration des lits de rivières alpines, c’est-à-dire avec différents arrangements et degrés de colmatage du lit par des sédiments fins. Les lits unimodaux sont composés de graviers peu triés avec divers arrangements de surface. Les lits bimodaux sont composés d’une matrice de graviers peu triés dans laquelle des sédiments fins se sont infiltrés (sables ou limons). Les processus régissant le transport de graviers ont été mis en avant. Le transport de graviers est impacté par l’arrangement du lit, la concentration de sédiments fins dans la couche de charriage, et par le changement de propriétés du lit due à la présence de sédiments fins (cohésion, perméabilité du lit). Plus le lit est arrangé, plus le transport est difficile. Plus la couche de charriage est concentrée en sédiments fins, plus le transport est facile. La forme des sédiments fins est aussi un facteur important pouvant modifier le transport des graviers. La présence de sédiments fins cohésifs dans la matrice peut considérablement réduire le taux de graviers transportés. Un modèle conceptuel a été développé pour résumer les différents processus contrôlant le transport de graviers. Il décrit le comportement des graviers dans les différentes configurations étudiées. L’outil proposé peut aider à comprendre, estimer et interpréter le transport de graviers. Il a été appliqué et discuté sur un cas de terrain sur la rivière de l’Arc. Basé sur ce modèle, nous avons proposé une nouvelle analyse dimensionnelle pour la construction d’un modèle de prédiction de transport solide prenant en compte des paramètres décrivant l’arrangement du lit, les propriétés géotechniques du lit et la présence de sédiments fins
This PhD thesis aims to understand gravel dynamics in Alpine rivers at low bed shear stress using laboratory experiments. Alpine river beds are often poorly sorted and composed of sediments ranging from clay to pebble. To understand interactions between these classes is an issue for predicting bedload rate. Laboratory experiments were performed in a 18m long and 1m wide flume, under unsteady flows. Two types of bed were investigated: unimodal and bimodal beds. A particular attention was paid to the bed construction, which was conducted in order to obtain a nature-like bed 12with different bed arrangements and degrees of clogging. Unimodal beds were made of moderately sorted gravels with different bed surface arrangements. Bimodal beds were made of moderately sorted gravels in which fine sediments (sand or silt) were infiltrated. Gravel rate was found to be impacted by the bed arrangement degree, the fine sediment concentration within the bedload layer and the changes in bed properties due to fine sediment presence (bed cohesion, bed permeability). The more packed the bed is; the more difficult it is to move gravels. The more concentrated in fine sediment the bedload layer is; the easier the transport of gravels is. The shape of fine sediments can also be an important factor for modifying the gravel rate. The presence of cohesive fine sediments within the bed matrix reduces significantly the gravel rate. A conceptual model was developed to recap the different processes controlling gravel transport. It provides a phenomenological description of the overall bed responses to a hydrograph. This tool is designed to help understanding, estimating or interpreting gravel transport in Alpine rivers. The conceptual model was discussed and applied to a field case made on the Arc River. Using the model, we also suggest a new dimensionless analysis for the construction of a bedload predicting model involving parameters describing bed arrangement, bed properties and fine sediment presence
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Mohammadi, Mirali. "Resistance to flow and the influence of boundary shear stress on sediment transport in smooth rigid boundary channels." Thesis, University of Birmingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.551283.

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Books on the topic "Menter Shear stress transport"

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Sturm, Terry W. Estimating critical shear stress of bed sediment for improved prediction of bridge contraction scour in Georgia: Final report. Forest Park, Ga.]: Dept. of Transportation, Office of Materials and Research, 2008.

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Mohammadi, Mirali. Resistance to flow and the influence of boundary shear stress on sediment transport in smooth rigid boundary channels. Birmingham: University of Birmingham, 1998.

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National Aeronautics and Space Administration (NASA) Staff. Recalibration of the Shear Stress Transport Model to Improve Calculation of Shock Separated Flows. Independently Published, 2019.

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New Hypothesis on the Anisotropic Reynolds Stress Tensor for Turbulent Flows : Volume II: Practical Implementation and Applications of an Anisotropic Hybrid K-Omega Shear-Stress Transport/Stochastic Turbulence Model. Springer International Publishing AG, 2020.

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Könözsy, László. New Hypothesis on the Anisotropic Reynolds Stress Tensor for Turbulent Flows : Volume II: Practical Implementation and Applications of an Anisotropic Hybrid K-Omega Shear-Stress Transport/Stochastic Turbulence Model. Springer International Publishing AG, 2021.

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Escudier, Marcel. Turbulent flow. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198719878.003.0018.

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In this chapter the principal characteristics of a turbulent flow are outlined and the way that Reynolds’ time-averaging procedure, applied to the Navier-Stokes equations, leads to a set of equations (RANS) similar to those governing laminar flow but including additional terms which arise from correlations between fluctuating velocity components and velocity-pressure correlations. The complex nature of turbulent motion has led to an empirical methodology based upon the RANS and turbulence-transport equations in which the correlations are modelled. An important aspect of turbulent flows is the wide range of scales involved. It is also shown that treating near-wall turbulent shear flow as a Couette flow leads to the Law of the Wall and the log law. The effect of surface roughness on both the velocity distribution and surface shear stress is discussed. It is shown that the distribution of mean velocity within a turbulent boundary layer can be represented by a linear combination of the near-wall log law and an outer-layer Law of the Wake.
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Wentzel, Jolanda J., Ethan M. Rowland, Peter D. Weinberg, and Robert Krams. Biomechanical theories of atherosclerosis. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780198755777.003.0012.

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Atherosclerosis, the disease underlying most heart attacks and strokes, occurs predominantly at certain well-defined sites within the arterial system. Its development may therefore depend not only on systemic risk factors but also on locally varying biomechanical forces. There are three inter-related theories explaining the effect of biomechanics on atherosclerosis. In the first theory, a central role is played by lipid transport into the vessel wall, which varies as a result of mechanical forces. In the second theory, haemodynamic wall shear stress-the frictional force per unit area of endothelium arising from the movement of blood-activates signalling pathways that affect endothelial cell properties. In the third, strain-the stretch of the wall arising from changes in blood pressure-is the key biomechanical trigger. All three theories are discussed from historical, molecular, and clinical perspectives.
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Book chapters on the topic "Menter Shear stress transport"

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Yamaguchi, Takami, Atushi Nakano, and Sotaro Hanai. "Three Dimensional Shear Stress Distribution around Small Atherosclerotic Plaques with Steady and Unsteady Flow." In Biomechanical Transport Processes, 173–82. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4757-1511-8_20.

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Könözsy, László. "The k- $$\omega $$ ω Shear-Stress Transport (SST) Turbulence Model." In A New Hypothesis on the Anisotropic Reynolds Stress Tensor for Turbulent Flows, 57–66. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-13543-0_3.

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Dietrich, William E., and Peter Whiting. "Boundary shear stress and sediment transport in river meanders of sand and gravel." In Water Resources Monograph, 1–50. Washington, D. C.: American Geophysical Union, 1989. http://dx.doi.org/10.1029/wm012p0001.

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Liu, Tong, Jinsheng Cai, and Kun Qu. "Ice Accretion Simulation Based on Roughness Extension of Shear Stress Transport $$ \varvec{k} -\varvec{\omega} $$ Turbulence Model." In Lecture Notes in Electrical Engineering, 566–78. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-3305-7_46.

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El-Hennawi, Ahmed, Muhammed Eltahan, Mohammed Magooda, and Karim Moharm. "Numerical Study of an Unbalanced Oil Vane Pump Using Shear Stress Transport (SST) k − ω Turbulence Model." In Recent Advances in Engineering Mathematics and Physics, 87–98. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-39847-7_7.

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Ngouani, M. M. Siewe, Yong Kang Chen, R. Day, and O. David-West. "Low-Speed Aerodynamic Analysis Using Four Different Turbulent Models of Solver of a Wind Turbine Shroud." In Springer Proceedings in Energy, 149–54. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-63916-7_19.

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AbstractThis study presents the effect of four different turbulent models of solver on the aerodynamic analysis of a shroud at wind speed below 6 m/s. The converting shroud uses a combination of a cylindrical case and an inverted circular wing base which captures the wind from a 360° direction. The CFD models used are: the SST (Menter) k-ω model, the Reynolds Stress Transport (RST) model, the Improved Delay Detached Eddies Simulation model (IDDES) SST k-ω model and the Large Eddies Simulation Wall Adaptive model. It was found that all models have predicted a convergent surface pressure. The RST, the IDDES and the WALE LES are the only models which have well described regions of pressure gradient. They have all predicted a pressure difference between the planes (1–5) which shows a movement of the air from the lower plane 1 (inlet) to the higher plane 5 (outlet). The RST and IDDES have predicted better vorticities on the plane 1 (inlet). It was also found that the model RST, IDDES, and WALE LES have captured properly the area of turbulences across the internal region of the case. All models have predicted the point of flow separation. They have also revealed that the IDDES and the WALE LES can capture and model the wake eddies at different planes. Thus, they are the most appropriate for such simulation although demanding in computational power. The movement of air predicted by almost all models could be used to drive a turbine.
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Horst, U. Oebius. "Laboratory and insitu bed shear stress measurements." In Mechanics of Sediment Transport, 243–54. CRC Press, 2020. http://dx.doi.org/10.1201/9781003079019-32.

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Taki, K. "Critical shear stress for cohesive sediment transport." In Coastal and Estuarine Fine Sediment Processes, 53–61. Elsevier, 2000. http://dx.doi.org/10.1016/s1568-2692(00)80112-6.

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Yin, Xuewen, and Junfeng Zhang. "Shear Stress Variation and Plasma Viscosity Effect in Microcirculation." In Transport in Biological Media, 349–90. Elsevier, 2013. http://dx.doi.org/10.1016/b978-0-12-415824-5.00009-6.

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Knight, D. W., H. S. Patel, J. D. Demetriou, and M. E. Hamed. "Boundary shear stress distributions in open channel and closed conduit flows." In Mechanics of Sediment Transport, 33–40. CRC Press, 2020. http://dx.doi.org/10.1201/9781003079019-4.

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Conference papers on the topic "Menter Shear stress transport"

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Lodefier, Koen, Bart Merci, Chris De Langhe, and Erik Dick. "Transition Modelling With the SST Turbulence Model and an Intermittency Transport Equation." In ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/gt2003-38282.

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A transition model for describing bypass transition is presented. It is based on a two-equations k–ω model and a dynamic equation for intermittency factor. The intermittency factor is a multiplier of the turbulent viscosity computed by the turbulence model. Following a suggestion by Menter et al. [1], the start of transition is computed based on local variables. The choice of the Shear-Stress Transport (SST) model instead of a k–ε model is explained. The quality of the transition model, developed on flat plate test cases, is illustrated for cascades.
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Jefferson-Loveday, Richard J. "Differential Equation-Based Specification of Turbulence Integral Length Scales for Cavity Flows." In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-56451.

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A new modeling approach has been developed that explicitly accounts for expected turbulent eddy length scales in cavity zones. It uses a hybrid approach with Poisson and Hamilton-Jacobi differential equations. These are used to set turbulent length scales to sensible expected values. For complex rim-seal and shroud cavity designs, the method sets an expected length scale based on local cavity width which accurately accounts for the large-scale wake-like flow structures that have been observed in these zones. The method is used to generate length scale fields for three complex rim-seal geometries. Good convergence properties are found and a smooth transition of length scale between zones is observed. The approach is integrated with the popular Menter Shear Stress Transport (MSST) RANS turbulence model and reduces to the standard Menter model in the mainstream flow. For validation of the model, a transonic deep cavity simulation is performed. Overall the Poisson-Hamilton-Jacobi model shows significant quantitative and qualitative improvement over the standard Menter RANS model for both velocity and Reynolds stress measurements. In its current development, the approach has been extended through the use of an initial stage of length scale estimation using a Poisson equation. This essentially reduces the need for user objectivity. A key aspect of the approach is that the length scale is automatically set by the model and not by the modeler. Notably, the current method is readily implementable in an unstructured, parallel processing computational framework.
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Batther, Jagdeep, and Seongkyu Lee. "Investigation of Dynamic Stall Leading-Edge Flow Features at a Low Transitional Reynolds Number." In Vertical Flight Society 78th Annual Forum & Technology Display. The Vertical Flight Society, 2022. http://dx.doi.org/10.4050/f-0078-2022-17472.

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The unsteady laminar separation and subsequent dynamic stall vortex (DSV) formation is investigated on a NACA 0012 airfoil section subject to a constant pitch rate motion using Delayed Detached Eddy Simulations (DDES) in NASA's OVERFLOW 2.3 solver. This study focuses on the complex flow features during the initial DSVformation and analyzes the distinct mechanisms from which the vortex is formed. It is shown that DDES accurately predicts the bursting of a laminar separation bubble (LSB), which triggers the onset of a DSV. In parallel to studying the feasibility of DDES in terms of capturing distinct flow features compared to Large Eddy Simulation (LES) results, a turbulence model study is also carried out, analyzing the influence of stateof-the-art turbulent and transition models on the DSV formation and subsequent stall onset. These include the fully turbulent Spalart Allmaras (SA) turbulence model and three different transition models: SA Coder Amplification Factor Transport (AFT), SA Medida-Baeder ? ? �Re?t , and the Shear Stress Transport (SST) Langtry-Menter ? ? �Re?t . It is found that the Coder SA AFT model provides the closest results with LES and the SST Langtry-Menter model predicts the earlier on set of the DSV. The fully turbulent model shows an abrupt development of a turbulent separation bubble and the under-prediction of the lift coefficient at lower angles of attack. At higher angles of attack, after the collapse of the separation bubble, all the models provide similar trends with each other and LES results.
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Sleiti, A. K., and J. S. Kapat. "Comparison Between EVM and RSM Turbulence Models in Predicting Flow and Heat Transfer in Rib-Roughened Channels." In ASME 2004 Heat Transfer/Fluids Engineering Summer Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/ht-fed2004-56250.

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A 3-D analysis of two-equation eddy-viscosity (EVMs) and Reynolds stress (RSM) turbulence models and their application to solving flow and heat transfer in rotating rib-roughened internal cooling channels is the main focus of this study. The flow in theses channels is affected by ribs, rotation, buoyancy, bends and boundary conditions. The EVMs considered are: The standard k–ε Model: of Launder and Spalding Launder and Spalding [1], the Renormalization Group k-ε model: Yakhot and Orszag [2], the Realizable k-ε model Shur et al. [3], the standard k-ω Model, Wilcox Wilcox [4], and the Shear-Stress Transport (SST) k-ω Model, Menter [5]. The viscosity affected near wall region is resolved by enhanced near wall treatment using combined two-layer model with enhanced wall functions. The results for both stationary and rotating channels showed the advantages of Reynolds Stress Model (RSM), Gibson and Launder [6], Launder [7], Launder [8] in predicting the flow field and heat transfer compared to the isotropic EVMs that need corrections to account for streamline curvature, buoyancy and rotation.
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Voigt, Stefan, Berthold Noll, and Manfred Aigner. "Aerodynamic Comparison and Validation of RANS, URANS and SAS Simulations of Flat Plate Film-Cooling." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-22475.

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The present paper deals with the detailed numerical simulation of film cooling including conjugate heat transfer. Five different turbulence models are used to simulate a film cooling configuration. The models include three steady and two unsteady models. The steady RANS models are the Shear stress transport (SST) model of Menter, the Reynolds stress model of Speziale, Sarkar and Gatski and a k-ε explicit algebraic Reynolds stress model. The unsteady models are a URANS formulation of the SST model and a scale-adaptive simulation (SAS). The solver used in this study is the commercial code ANSYS CFX 11.0. The results are compared to available experimental data. These data include velocity and turbulence intensity fields in several planes. It is shown that the steady RANS approach has difficulties with predicting the flow field due to the high 3-dimensional unsteadiness. The URANS and SAS simulations on the other hand show good agreement with the experimental data. The deviation from the experimental data in velocity values in the steady cases is about 20% whereas the error in the unsteady cases is below 10%.
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Currie, Tom C. "Comparison of ω-Based Turbulence Models for Simulating Separated Flows in Transonic Compressor Cascades." In ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/98-gt-421.

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Separated flows in the DLR transonic compressor cascades TSG-91-8K and TSG-89-5 are simulated with a quasi-3D Navier-Stokes code using the zonal k-ω/k-ϵ “Shear Stress Transport” two-equation turbulence model of Menter and the multiscale Reynolds stress model of Wilcox. Both of these models use the specific turbulent dissipation rate ω as the length scale variable. The models are also used to simulate the low speed, separated flow, adverse pressure gradient test case of Driver. While both models predict results which are in good agreement with experiment for the latter test case, they yield relatively poor results, particularly for losses, for the cascade test cases, especially TSG-89-5 where separation occurs from both the suction and pressure surfaces. It is known from the cascade test results that the separations are laminar, so some improvement in agreement is achieved by suppressing transition to the separation points in the simulations. The poor accuracy of the models is believed to be related to severe non-equilibrium of turbulence production and dissipation predicted after the shock-induced separations.
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Ivanova, Elizaveta, Berthold Noll, and Manfred Aigner. "A Numerical Study on the Turbulent Schmidt Numbers in a Jet in Crossflow." In ASME Turbo Expo 2012: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-69294.

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This work presents a numerical study on the turbulent Schmidt numbers in jets in crossflow. This study contains two main parts. In the first part the problem of the proper choice of the turbulent Schmidt number in the Reynolds-Averaged Navier-Stokes (RANS) jet in crossflow mixing simulations is outlined. The results of RANS employing the shear-stress transport (SST) model of Menter and its curvature correction modification and different turbulent Schmidt number values are validated against experimental data. The dependence of the “optimal” value of the turbulent Schmidt number on the dynamic RANS model is studied. Furthermore a comparison is made with the large-eddy simulation (LES) results obtained using the WALE (Wall-Adapted Local Eddy Viscosity) model. The accuracy given by LES is superior in comparison to RANS results. This leads to the second part of the current study, in which the time-averaged mean and fluctuating velocity and scalar fields from LES are used for the evaluation of the turbulent viscosities, turbulent scalar diffusivities, and the turbulent Schmidt numbers in a jet in crossflow configuration. The values obtained from the LES data are compared with those given by the RANS modeling. The deviations are discussed and the possible ways for the RANS model improvements are outlined.
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Ibrahim, Mounir, Olga Kartuzova, and Ralph J. Volino. "Experimental and Computational Investigations of Separation and Transition on a Highly Loaded Low-Pressure Turbine Airfoil: Part 1 — Low Freestream Turbulence Intensity." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-68879.

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Boundary layer separation, transition and reattachment have been studied on a new, very high lift, low-pressure turbine airfoil. Experiments were done under low freestream turbulence conditions on a linear cascade in a low speed wind tunnel. Pressure surveys on the airfoil surface and downstream total pressure loss surveys were documented. Velocity profiles were acquired in the suction side boundary layer at several streamwise locations using hot-wire anemometry. Cases were considered at Reynolds numbers (based on the suction surface length and the nominal exit velocity from the cascade) ranging from 25,000 to 330,000. In all cases the boundary layer separated, but at high Reynolds number the separation bubble remained very thin and quickly reattached after transition to turbulence. In the low Reynolds number cases, the boundary layer separated and did not reattach, even when transition occurred. Three different CFD URANS (unsteady Reynolds averaged Navier-Stokes) models were utilized in this study (using Fluent CFD Code), the k-ω shear stress transport model, the ν2-fk-ε model, and the 4 equation Transition model of Menter. At Re = 25,000, the Transition model seems to perform the best. At Re = 100,000 the Transition model seems to perform the best also, although it under-predicts the pressure coefficient downstream of the suction peak. At Re = 300,000 all models perform very similar with each other. The Transition model showed a small bump in the pressure coefficient downstream from the suction peak indicating the presence of a small bubble at that location.
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Boroomand, Masoud, and Shirzad Hosseinverdi. "Numerical Investigation of Turbulent Flow Around a Stepped Airfoil at High Reynolds Number." In ASME 2009 Fluids Engineering Division Summer Meeting. ASMEDC, 2009. http://dx.doi.org/10.1115/fedsm2009-78294.

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This study presents the numerical simulation of flow development around NACA-2412 airfoil which utilized the backward facing step to explore the possibility of enhancing airfoil aerodynamic performance by trapped vortex lift augmentation. This article concentrate on the effect of separated flow and following vortex formation which is created by backward facing step on pressure distribution and subsequently on lift and drag coefficient. Reynolds number that based on the free stream velocity and airfoil chord is 5.7×106. The two-equation shear stress transport (SST) k-ω turbulence model of Menter is employed to determine accurately turbulent flow, as well as the recirculation pattern along the airfoil. The Reynolds-averaged Navier Stokes (RANS) equations are solved numerically using finite volume based solution with second-order upwind Roe’s scheme. Steps are located on both suction side and pressure side of the airfoil, at different locations, different lengths and various depths in order to determine their effects on lift, lift to drag ratio and near stall behavior. The modeling results showed that all stepped airfoil cases studied experienced higher drag compared to the base airfoil. Considerable lift enhancement was found for airfoil with backward facing step on pressure side at all values of angle of attack because of trapped vortex. The results suggest that the steps on the lower surface that extended back to trailing edge can lead to more enhancement of lift to drag ratio for some angles of attack; while the rear locations for the step on upper surface was found to have negative effect on lift to drag ratio. Based on this study, the backward facing step on suction surface offers no discernable advantages over the conventional airfoil but showed some positive effect on delaying stall.
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Barbier, C., and E. Dominguez-Ontiveros. "Improving Computational Fluid Dynamics Simulations for the Spallation Neutron Source Jet-Flow Target." In ASME 2016 Fluids Engineering Division Summer Meeting collocated with the ASME 2016 Heat Transfer Summer Conference and the ASME 2016 14th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/fedsm2016-7671.

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A liquid mercury target is used at Oak Ridge National Laboratory’s (ORNL [1]) Spallation Neutron Source (SNS [2]) to generate neutrons. The mercury is flowing in a stainless steel containment vessel for neutron spallation, but also to cool the vessel itself. Computational Fluid Dynamics (CFD) simulations have been used to estimate the temperature and pressure fields needed for the thermal stress analysis. Because of the geometry complexity, the high turbulence number, and the computational time requirements, generating a quality mesh that can accurately capture the flow and heat transfer has always been a challenge. However, with today’s High Performance Computing (HPC) advances, larger and larger meshes can now be used and better accuracy can be achieved. In this study, two meshing methods were used for the SNS jet-flow target: automatic tetrahedral method (ANSYS meshing) and manual hexahedral meshing (ICEM-CFD). Both methods are compared in terms of quality, size, ease of generation, convergence, and user-friendliness. Both meshes were used with ANSYS-CFX to simulate the steady, Newtonian, single phase, isothermal, incompressible and turbulent flow in the target. The Shear Stress Transport (SST) k-ω model developed by Menter [3] was used for turbulence modeling. The accuracy of the CFD simulations are tested against experimental data presented in the current paper. An in-depth series of Particle Image Velocimetry (PIV) measurements performed on a “visual jet-flow target”, an acrylic replica target running with water, are presented in the paper. Since flow measurements in mercury are difficult, a water loop was built to investigate the flow in the target and a potential gas injection in the flow to mitigate the pressure wave [4]. A PIV system on a precise translation stage was setup on the water loop to perform detailed and accurate PIV measurements. Mean flow velocity fields were used to validate the CFD simulations. The paper concludes on the choice for mesh generation for future target analysis, and the path forward for CFD simulations for the future SNS targets.
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Reports on the topic "Menter Shear stress transport"

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Pullammanappallil, Pratap, Haim Kalman, and Jennifer Curtis. Investigation of particulate flow behavior in a continuous, high solids, leach-bed biogasification system. United States Department of Agriculture, January 2015. http://dx.doi.org/10.32747/2015.7600038.bard.

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Recent concerns regarding global warming and energy security have accelerated research and developmental efforts to produce biofuels from agricultural and forestry residues, and energy crops. Anaerobic digestion is a promising process for producing biogas-biofuel from biomass feedstocks. However, there is a need for new reactor designs and operating considerations to process fibrous biomass feedstocks. In this research project, the multiphase flow behavior of biomass particles was investigated. The objective was accomplished through both simulation and experimentation. The simulations included both particle-level and bulk flow simulations. Successful computational fluid dynamics (CFD) simulation of multiphase flow in the digester is dependent on the accuracy of constitutive models which describe (1) the particle phase stress due to particle interactions, (2) the particle phase dissipation due to inelastic interactions between particles and (3) the drag force between the fibres and the digester fluid. Discrete Element Method (DEM) simulations of Homogeneous Cooling Systems (HCS) were used to develop a particle phase dissipation rate model for non-spherical particle systems that was incorporated in a two-fluid CFDmultiphase flow model framework. Two types of frictionless, elongated particle models were compared in the HCS simulations: glued-sphere and true cylinder. A new model for drag for elongated fibres was developed which depends on Reynolds number, solids fraction, and fibre aspect ratio. Schulze shear test results could be used to calibrate particle-particle friction for DEM simulations. Several experimental measurements were taken for biomass particles like olive pulp, orange peels, wheat straw, semolina, and wheat grains. Using a compression tester, the breakage force, breakage energy, yield force, elastic stiffness and Young’s modulus were measured. Measurements were made in a shear tester to determine unconfined yield stress, major principal stress, effective angle of internal friction and internal friction angle. A liquid fludized bed system was used to determine critical velocity of fluidization for these materials. Transport measurements for pneumatic conveying were also assessed. Anaerobic digestion experiments were conducted using orange peel waste, olive pulp and wheat straw. Orange peel waste and olive pulp could be anaerobically digested to produce high methane yields. Wheat straw was not digestible. In a packed bed reactor, anaerobic digestion was not initiated above bulk densities of 100 kg/m³ for peel waste and 75 kg/m³ for olive pulp. Interestingly, after the digestion has been initiated and balanced methanogenesis established, the decomposing biomass could be packed to higher densities and successfully digested. These observations provided useful insights for high throughput reactor designs. Another outcome from this project was the development of low cost devices to measure methane content of biogas for off-line (US$37), field (US$50), and online (US$107) applications.
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