Relevant bibliographies by topics / Trapped vortex

Academic literature on the topic 'Trapped vortex'

Author: Grafiati
Published: 14 March 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Contents

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Trapped vortex.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Trapped vortex"

1

Vengadesan, S., and C. Sony. "Enhanced vortex stability in trapped vortex combustor." Aeronautical Journal 114, no. 1155 (May 2010): 333–37. http://dx.doi.org/10.1017/s000192400000378x.

Full text
Abstract:
Abstract The Trapped Vortex Combustor (TVC) is a new design concept in which cavities are designed to trap a vortex flow structure established through the use of driver air jets located along the cavity walls. TVC offers many advantages when compared to conventional swirl-stabilised combustors. In the present work, numerical investigation of cold flow (non-reacting) through the two-cavity trapped vortex combustor is performed. The numerical simulation involves passive flow through the two-cavity TVC to obtain an optimum cavity size to trap stable vortices inside the second cavity and to observe the characteristics of the two cavity TVC. From the flow attributes, it is inferred that vortex stability is achieved by circulation and the vortex is trapped inside when a second afterbody is added.
APA, Harvard, Vancouver, ISO, and other styles
2

Li, Qiong, Meng Meng Zhao, and Fei Xing. "Experimental Investigation of Airflow Distribution for a Novel Combustor Mode." Applied Mechanics and Materials 284-287 (January 2013): 743–47. http://dx.doi.org/10.4028/www.scientific.net/amm.284-287.743.

Full text
Abstract:
This paper investigated the airflow distribution performance of the combustor which utilized trapped vortex in the cavity to improve the flame stability. Hole-filling method was used to study trapped vortex combustor airflow distribution at normal temperature and pressure condition. The influence of inlet velocity and mainstream flow-passage height were investigated. The results show that, inlet velocity hardly impacts the airflow distribution of trapped vortex combustor, but chamber height is a key parameter for airflow distribution. The size, number and opening area of the holes in trapped vortex combustor are important to airflow distribution, and increasing cavity back body air flow could bring well lean blowout limit. The research results may serve as a useful reference in further development and engineering application of trapped vortex combustor.
APA, Harvard, Vancouver, ISO, and other styles
3

Garcia, Darwin L., and Joseph Katz. "Trapped Vortex in Ground Effect." AIAA Journal 41, no. 4 (April 2003): 674–78. http://dx.doi.org/10.2514/2.1997.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Molina-Terriza, Gabriel, Lluis Torner, Ewan M. Wright, Juan J. García-Ripoll, and Víctor M. Pérez-García. "Vortex revivals with trapped light." Optics Letters 26, no. 20 (October 15, 2001): 1601. http://dx.doi.org/10.1364/ol.26.001601.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Deng, Yangbo, and Fengmin Su. "Low emissions trapped vortex combustor." Aircraft Engineering and Aerospace Technology 88, no. 1 (January 4, 2016): 33–41. http://dx.doi.org/10.1108/aeat-09-2013-0172.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

DAVYDOVA, T. A., and V. M. LASHKIN. "Drift-wave trapping by drift vortices." Journal of Plasma Physics 58, no. 1 (July 1997): 11–18. http://dx.doi.org/10.1017/s002237789700562x.

Full text
Abstract:
The possibility for a drift dipole vortex to trap free drift waves is demonstrated. Drift perturbations can be trapped near the centre of the vortex or at its sides. The localization domain and eigenfrequencies of trapped modes are obtained.
APA, Harvard, Vancouver, ISO, and other styles
7

Hsu, K. Y., L. P. Goss, and W. M. Roquemore. "Characteristics of a Trapped-Vortex Combustor." Journal of Propulsion and Power 14, no. 1 (January 1998): 57–65. http://dx.doi.org/10.2514/2.5266.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Zhu, Qing-Li, and Jin An. "Surface Excitations, Shape Deformation, and the Long-Time Behavior in a Stirred Bose–Einstein Condensate." Condensed Matter 3, no. 4 (November 25, 2018): 41. http://dx.doi.org/10.3390/condmat3040041.

Full text
Abstract:
The surface excitations, shape deformation, and the formation of persistent current for a Gaussian obstacle potential rotating in a highly oblate Bose–Einstein condensate (BEC) are investigated. A vortex dipole can be produced and trapped in the center of the stirrer even for the slow motion of the stirring beam. When the angular velocity of the obstacle is above some critical value, the condensate shape can be deformed remarkably at the corresponding rotation frequency followed by surface wave excitations. After a long enough time, a small number of vortices are found to be either trapped in the condensate or pinned by the obstacle, and a vortex dipole or several vortices can be trapped at the beam center, which provides another way to manipulate the vortex.
APA, Harvard, Vancouver, ISO, and other styles
9

Chen, Song, Randy S. M. Chue, Simon C. M. Yu, and Jörg U. Schlüter. "Spinning Effects on a Trapped Vortex Combustor." Journal of Propulsion and Power 32, no. 5 (September 2016): 1133–45. http://dx.doi.org/10.2514/1.b36005.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Kunze, Eric, and Emmanuel Boss. "A Model for Vortex-Trapped Internal Waves." Journal of Physical Oceanography 28, no. 10 (October 1998): 2104–15. http://dx.doi.org/10.1175/1520-0485(1998)028<2104:amfvti>2.0.co;2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Trapped vortex"

1

Madarassy, E. J. M. "Vortex motion in trapped Bose-Einstein condensates." Thesis, University of Newcastle Upon Tyne, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485606.

Full text
Abstract:
We have performed numerical simulations of various vortex configurations in a trapped BoseEinstein condensate by solving the two-dimensional Gross-Pitaevskii equation in the presence of a simple model of interaction between the condensate and the finite temperature thermal cloud that surrounds it. In that interaction the non-condensed thermal cloud acts as a source of dissipation with a damping effect of excitations. In the case ora single vortex and a vortex - anti vortex pair, we have found that the path of the vortices depends on the initial position, the initial separation distance if the case of two vortices and dissipation. This motion is periodic and it was found that sound waves are created by vortex motion; the intensity was stronger when the initial vortex separation distance was smaller. We have calculated the sound energy as the difference between the kinetic energy and the vortex energy. With no dissipation the vortices followed the same path with a slight oscillation due to the sound waves. We found that the smaller the initial vortex separation distance do is, the larger the sound production. The period, frequency, translation speed, sound energy and vortex energy were measured for different initial separation distances do and for different dissipation parameters 'Y. In the case of motion of one vortex, the connection between the dissipation 'Y and the friction coefficients, a and a' was studied as well. To create a simple turbulent state, we put eight pairs of vortex - anti vortex at random positions in the condensate with initial separation distance do =1.8 between them. 'Ve have studied the decay rate of the total energy, kinetic energy, quantum energy, trap energy and the z - component of the angular momentum together with the increase rate of the internal energy. Finally, we finished our investigation by putting randomly vortex - anti vortex pairs and studied the decrease of the number of vortices with time t. We found that the decrease is exponential.
APA, Harvard, Vancouver, ISO, and other styles
2

Zope, Anup Devidas. "Response surface analysis of trapped-vortex augmented airfoils." Thesis, Mississippi State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1604198.

Full text
Abstract:

In this study, the effect of a passive trapped-vortex cell on lift to drag (L/D) ratio of an FFA-W3-301 airfoil is studied. The upper surface of the airfoil was modified to incorporate a cavity defined by seven parameters. The L/D ratio of the airfoil is modeled using a radial basis function metamodel. This model is used to find the optimal design parameter values that give the highest L/D. The numerical results indicate that the L/D ratio is most sensitive to the position on an airfoil’s upper surface at which the cavity starts, the position of the end point of the cavity, and the vertical distance of the cavity end point relative to the airfoil surface. The L/D ratio can be improved by locating the cavity start point at the point of separation for a particular angle of attack. The optimal cavity shape (o19_aXX) is also tested for a NACA0024 airfoil.

APA, Harvard, Vancouver, ISO, and other styles
3

Scherer, David Rene. "Vortex Formation by Merging and Interference of Multiple Trapped Bose-Einstein Condensates." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/194657.

Full text
Abstract:
An apparatus for producing atomic-gas Bose-Einstein condensates (BECs) of 87-Rb atoms is described. The apparatus produces 87-Rb BECs in a dual-chamber vacuumsystem that incorporates magnetic transport of trapped atoms from the magneto-optical trapping cell to the BEC production cell via the operation of a series of overlapping magnet coils. The design, construction, and operation of the apparatus are described in detail.The apparatus is used to study the creation of quantized vortices in BECs by the merging and interference of multiple trapped condensates. In this experiment, a single harmonic potential well is partitioned into three sections by an optical barrier,enabling the simultaneous formation of three independent, uncorrelated BECs. The BECs may either merge together during their growth, or, for high-energy barriers, the BECs can be merged together by barrier removal after their formation. Either process may instigate vortex formation in the resulting BEC, depending on the initially indeterminate relative phases of the condensates and the merging rate.
APA, Harvard, Vancouver, ISO, and other styles
4

Bouferrouk, Abdessalem. "A discrete vortex method analysis tool for control of flows with trapped vortices." Thesis, University of Southampton, 2007. https://eprints.soton.ac.uk/49925/.

Full text
Abstract:
Passive and active control studies have been conducted to investigate the feasibility of stabilising a trapped vortex. Passive stabilisation is achieved using distributed steady wall suction. An enhanced aerodynamic performance with lower drag and higher lift has been achieved as a result of passive stabilisation, but only up to moderate suction rates. When the trapped vortex is stabilised, vortex shedding is completely suppressed and flow unsteadiness is significantly reduced. Compared with steady suction, pulsed suction reduces the required suction rate for stabilisation by over 50% at an optimum pulsing frequency. Using slow suction reduction from a stable state, savings in mean suction are also possible provided the rate of suction reduction is small enough. It appears, however, that such reduction is dependent on the specific shape of the aerofoil’s cavity. A bifurcation analysis has shown that the loss of stability of a trapped vortex, from a stable state to unstable cortex shedding, is also dependent on the cavity configuration. A linear feedback controller with an optimum gain G extends the slow suction reduction results by achieving stabilisation at a reduced mean suction compared with passive stabilisation. Using DVM’s ability to simulate unsteady suction and blowing, active stabilisation using vorticity flux control achieves 16% reduction in mean flow rate compared with linear control and 19% compared with passive stabilisation. The pulsed suction technique remains the most efficient method of stabilisation. Simplified power calculations have shown suction control to be effective but only within a small range of suction rates. Using DVM’s capability of providing controlled input-output data, a linear System Identification study of the trapped vortex has resulted in a dynamical model description of a stable trapped vortex which, despite being a crude estimate, is useful in future stabilisation studies.
APA, Harvard, Vancouver, ISO, and other styles
5

Xavier, Pradip. "Investigation of flame stabilization mechanisms in a premixed combustor using a hot gas cavity-based flame holder." Thesis, Rouen, INSA, 2014. http://www.theses.fr/2014ISAM0016/document.

Full text
Abstract:
Cette thèse décrit l'étude d'une chambre de combustion innovante de type Trapped Vortex Combustor (TVC): ce concept utilise des cavités de gaz chauds pour stabiliser des flammes prémélangées pauvres. A partir d'une étude globale d'un point de fonctionnement instable, l'approche scientifique vise à différencier l'impact des différents mécanismes physiques. La structure de l'écoulement inerte est étudiée finement avant de mener une étude spatio-Temporelle sur un point de fonctionnement instable, en conditions réactives. L'analyse permet de comprendre les interactions entre la structure de la flamme, la topologie de l'écoulement et l'acoustique du brûleur. Différents mécanismes pilotant l'apparition d'instabilités de combustion sont mis en évidence, et des recommandations sont fournies afin de les supprimer. Un vérification a posteriori permet de valider l'importance de ces mécanismes, notamment grâce à la détermination de diagrammes de stabilité de flamme
This thesis describes the investigation of an innovative trapped vortex combustor (TVC): this concept uses recirculating hot gas flow trapped in cavities to stabilize lean main flames. Based on a global investigation of an unstable operating condition, the scientific strategy aims to treat separately the different physical mechanisms. The inert flow structure is analyzed prior to leading a spatio-Temporal study on an unstable mode. This investigation aims to understand the flaine-Flow-Acoustic interactions in the combustor. Several mechanisms piloting combustion instabilities are highlighted, and recommandations are provided in order to suppress them. An a posteriori check validate the preponderance of these mechanisms, in particular with the determination of stability flaine diagrams
APA, Harvard, Vancouver, ISO, and other styles
6

Malo-Molina, Faure Joel. "Numerical study of innovative scramjet inlets coupled to combustors using hydrocarbon-air mixture." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33906.

Full text
Abstract:
To advance the design of hypersonic vehicles, high-fidelity multi-physics CFD is used to characterize 3-D scramjet flow-fields in two novel streamline traced configurations. The two inlets, Jaws and Scoop, are analyzed and compared to a traditional rectangular inlet used as a baseline for on/off-design conditions. The flight trajectory conditions selected are Mach 6 and a dynamic pressure of 1,500 psf (71.82 kPa). Analysis of these hypersonic inlets is performed to investigate distortion effects downstream with multiple single cavity combustors acting as flame holders, and several fuel injection strategies. The best integrated scramjet inlet/combustor design is identified. The flow physics is investigated and the integrated performance impact of the two innovative scramjet inlet designs is quantified. Frozen and finite rate chemistry is simulated with 13 gaseous species and 20 reactions for an Ethylene/air finite-rate chemical model. In addition, URANS and LES modeling are compared to explore overall flow structure and to contrast individual numerical methods. The flow distortion in Jaws and Scoop is similar to some of the distortion in the traditional rectangular inlet, despite design differences. The baseline and Jaws performance attributes are stronger than Scoop, but Jaws accomplishes this while eradicating the cowl lip interaction, and lessening the total drag and spillage penalties. The innovative inlets work best on-design, whereas for off-design, the traditional inlet is best. Early pressure losses and flow distortions in the isolator aid the mixing of air and fuel, and improve the overall efficiency of the system. Although the trends observed with and without chemical reactions are similar, the former yields roughly 10% higher mixing efficiency and upstream reactions are present. These show a significant impact on downstream development. Unsteadiness in the combustor increases the mixing efficiency, varying the flame anchoring and combustion pressure effects upstream of the step.
APA, Harvard, Vancouver, ISO, and other styles
7

Burguburu, Joseph. "Etude expérimentale de la stabilité d’une flamme dans une chambre de combustion aéronautique par recirculation de gaz brûlés et par ajout d’hydrogène." Thesis, Rouen, INSA, 2012. http://www.theses.fr/2012ISAM0010/document.

Full text
Abstract:
Les réglementations sur les NOx émis par les avions sont sévères. Les techniques les réduisant ont des inconvénients. Pour les supprimer, deux pistes sont explorées. La première modifie l'architecture des chambres de combustion et les stabilise par une cavité. La seconde dope le kérosène au ralenti.Peu d'information est disponible sur les mécanismes de stabilisation et sur la structure de flamme des Trapped Vortex Combustor. Pour y remédier, un TVC est construit. L'étude de l'écoulement à froid ainsi que l'étude temporellement résolue de la flamme, mettent en avant les éléments stabilisateurs et déstabilisateurs. L'impact de la structure de flamme sur les émissions est évalué.La seconde partie porte sur l'effet de l'ajout d'hydrogène et de gaz de reformeur dans une chambre conventionnelle. Malgré une légère augmentation des émissions de NOx, l'ajout de composés hydrogénés réduit fortement les émissions de CO, augmente la stabilité et réduit la limite d'extinction pauvre
Environmental standards on aircraff NOx emissions are strict. Technics for reducing them have drawbacks. Two options are explored in this study to supress them. The first one is to fundamentally change the current combustion chamber architecture, to stabilize them by a cavity, the second, to dope fuel at idle.Little information on the mechanisms of stabilization and on the flame structure on Trapped Vortex Combustor is available. To remedy this, a TVC is built. The stabilizing ans destabilizing parameters are pointed out by the cold flow investigation and the temporally resolved study of the combustion. The impact of the flame structure on pollutant emissions is also considered.The second part of this stud, deals with the addition of pure hydrogen an of reformer gas in a conventional combustuion chamber. Despite a slight increase in NOx emissions, the addition of hydrogenated compounds reduces drastically CO emissions, increases the flame stability and reduces the LBO limit
APA, Harvard, Vancouver, ISO, and other styles
8

Merlin, Cindy. "Simulation numérique de la combustion turbulente : Méthode de frontières immergées pour les écoulements compressibles, application à la combustion en aval d’une cavité." Thesis, Rouen, INSA, 2011. http://www.theses.fr/2011ISAM0020/document.

Full text
Abstract:
Une méthode de frontières immergées est développée pour la simulation d’écoulements compressibles et validée au travers de cas-tests spécifiques (réflexion d’ondes acoustiques et quantification de la conservation de la masse dans des canaux inclinés). La simulation aux grandes échelles (LES) d’une cavité transsonique est ensuite présentée. Le bouclage aéro-acoustique, très sensible aux conditions aux limites, est reproduit avec précision par la LES dans le cas où les parois sont immergées dans un maillage structurée. La comparaison des stratégies de modélisation de sous-maille pour cet écoulement transsonique et l’adaptation des filtres en présence de frontières immergées sont également discutées. Le rôle, souvent sous-estimé, du schéma de viscosité artificiel, est quantifié.Dans la dernière partie du manuscrit, des études sont réalisées pour aider au dimensionnement d’un nouveau concept de chambre de combustion où la flamme est stabilisée par la recirculation de gaz brûlés dans une cavité (chambre TVC pour Trapped Vortex Combustor). La modélisation de la combustion turbulente est basée sur une chimie tabulée, couplée à une fonction densité de probabilité présumée (PCM-FPI). L’étude de la dynamique de la flamme est réalisée pour diverses conditions de fonctionnement (débit de l’écoulement principal et présence ou non d’un swirl). Les spécificités de mise en œuvre de la simulation d’un écoulement de ce type sont discutées et un soin particulier est apporté au traitement de la condition de sortie, qui constitue un point sensible de la chaîne de modélisation. Les phénomènes d’instabilités et de retour de la flamme sont mis en évidence ainsi que les modifications à apporter au dispositif afin de minimiser ces effets. L’existence d’un cycle limite acoustique est souligné et une formule permettant d’anticiper le niveau des fluctuations de pression est proposée et validée. Une correction au modèle PCM-FPI est présentée afin de préserver la vitesse de flamme et d’assurer une reproduction plus précise de la dynamique de flamme
An immersed boundary method has been developed for the simulation of compressible flow and validated with reference test cases (pressure wave reflection and quantification of mass conservation for various inclined channels). Large Eddy Simulation (LES) of a transonic cavity is then presented. The aeroacoustic feedback loop, which is highly sensitive to the boundary conditions, was accurately reproduced where the walls are immersed inside a structured grid. The comparison between the modeling approaches for this transonic flow and the correction of the filtering operation near immersed boundaries are also discussed. The often underestimated role of the numerical artificial dissipation is also quantified.In the last part of this manuscript, many studies are realized to help in the design of a new combustion chamber for Trapped Vortex Combustor (TVC). The turbulent combustion model is based on tabulated chemistry and a presumed probability density function (PCM-FPI) method.The flame dynamics is studied for various operating conditions (flowrate of the main flow and presence of swirl motion). Details concerning the realization of such a flow are discussed and special care is taken for the treatment of the most sensitive outlet boundary condition. The phenomena of combustion instabilities and of flame backflow are highlighted along with the modifications to be made for the device to minimize these effects. The existence of a acoustic limit cycle is emphasized and a formula is proposed and validated to anticipate the level of pressure fluctuations. Finally a correction to the PCM-FPI model is suggested to preserve the flame front speed and to ensure a more accurate description of the flame dynamics
APA, Harvard, Vancouver, ISO, and other styles
9

Singhal, Atul. "Single Cavity Trapped Vortex Combustor Dynamics : Experiments & Simulations." Thesis, 2009. http://hdl.handle.net/2005/1123.

Full text
Abstract:
Trapped Vortex Combustor (TVC) is a relatively new concept for potential use in gas turbine engines addressing ever increasing demands of high efficiency, low emissions, low pressure drop, and improved pattern factor. This concept holds promise for future because of its inherent advantages over conventional swirl-stabilized combustors. The main difference between TVC and a conventional gas turbine combustor is in the way combustion is stabilized. In conventional combustors, flame is stabilized because of formation of toroidal flow pattern in the primary zone due to interaction between incoming swirling air and fuel flow. On the other hand, in TVC, there is a physical cavity in the wall of combustor with continuous injection of air and fuel leading to stable and sustained combustion. Past work related to TVC has focussed on use of two cavities in the combustor liner. In the present study, a single cavity combustor concept is evaluated through simulation and experiments for applications requiring compact combustors such as Unmanned Aerial Vehicles (UAVs) and cruise missiles. In the present work, numerical simulations were initially performed on a planar, rectangular single-cavity geometry to assess sensitivity of various parameters and to design a single-cavity TVC test rig. A water-cooled, modular, atmospheric pressure TVC test rig is designed and fabricated for reacting and non-reacting flow experiments. The unique features of this rig consist of a continuously variable length-to-depth ratio (L/D) of the cavity and optical access through quartz plates provided on three sides for visualization. Flame stabilization in the single cavity TVC was successfully achieved with methane as fuel, and the range of flow conditions for stable operation were identified. From these, a few cases were selected for detailed experimentation. Reacting flow experiments for the selected cases indicated that reducing L/D ratio and increasing cavity-air velocity favour stable combustion. The pressure drop across the single-cavity TVC is observed to be lower as compared to conventional combustors. Temperatures are measured at the exit using thermocouples and corrected for radiative losses. Species concentrations are measured at the exit using an exhaust gas analyzer. The combustion efficiency is observed to be around 98-99% and the pattern factor is observed to be in the range of 0.08 to 0.13. High-speed imaging made possible by the optical access indicates that the overall combustion is fairly steady, and there is no major vortex shedding downstream. This enabled steady-state simulations to be performed for the selected cases. Insight from simulations has highlighted the importance of air and fuel injection strategies in the cavity. From a mixing and combustion efficiency standpoint, it is desirable to have a cavity vortex that is anti-clockwise. However, the natural tendency for flow over a cavity is to form a vortex that is clockwise. The tendency to blow-out at higher inlet flow velocities is thought to be because of these two opposing effects. This interaction helps improve mixing, however leads to poor flame stability unless cavity-air velocity is strong enough to support a strong anti-clockwise vortex in the cavity. This basic understating of cavity flow dynamics can be used for further design improvements in future to improve flame stability at higher inlet flow velocities and eventually lead to the development of a practical combustor.
APA, Harvard, Vancouver, ISO, and other styles
10

李靜宜. "Symmetric Vortex Solution on Gross-Pitaevskii Equation with trapped potential." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/68789309479865187597.

Full text
Abstract:
碩士
國立中正大學
應用數學研究所
88
In this article, I discuss symmetric vortex solution on Gross-Pitaevskii equation with trapped potential. I use polar coordinate to convert the PDE into ODE system. Moreover, I discuss the type of the solution of ODE equation. This solution is called the symmetric vortex solution. Finally I discuss the Regularity of the steady state of the Gross-Pitaevskii equation with trapped potential.
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Trapped vortex"

1

Andreja, Brankovic, and NASA Glenn Research Center, eds. Measurement and computation of supersonic flow in a lobed diffuser-mixer for trapped vortex combustors. [Cleveland, Ohio]: National Aeronautics and Space Administration, Glenn Research Center, 2002.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Powers, Sheryll Goecke. Flight and wind-tunnel measurements showing base drag reduction provided by a trailing disk for high Reynolds number turbulent flow for subsonic and transonic Mach numbers. [Washington, DC]: National Aeronautics and Space Administration, Scientific and Technical Information Branch, 1988.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Powers, Sheryll Goecke. Flight and wind-tunnel measurements showing base drag reduction provided by a trailing disk for high Reynolds number turbulent flow for subsonic and transonic Mach numbers. Edwards, Cal: Dryden Flight Research Facility, 1986.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

K, Huffman Jarrett, Fox Charles H, and United States. National Aeronautics and Space Administration. Scientific and Technical Information Branch., eds. Flight and wind-tunnel measurements showing base drag reduction provided by a trailing disk for high Reynolds number turbulent flow for subsonic and transonic Mach numbers. [Washington, DC]: National Aeronautics and Space Administration, Scientific and Technical Information Branch, 1988.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Zeitlin, Vladimir. Instabilities in Cylindrical Geometry: Vortices and Laboratory Flows. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198804338.003.0011.

Full text
Abstract:
Vortex solutions in cyclo-geostrophic equilibrium are described and their geostrophic and ageostrophic barotropic and baroclinic instabilities are studied along the lines of Chapter 10. Special attention is paid to centrifugal instability which, as the inertial instability of jets, is due to modes trapped in the anticyclonic shear in the vortex, and has asymmetric counterparts. Saturation of this instability is shown to exhibit some specific patterns. Instabilities of intense hurricane-like vortices are analysed and shown to be sensitive to fine details of the vortex profile. Nonlinear saturation of such instabilities exhibits typical secondary meso-vortex structures, and leads to intensification of the vortex. Special attention is paid to instabilities in laboratory flows in rotating cylindrical channels. Classification of these instabilities is given, and their nature, in terms of resonances between different wave modes, is established. Rigid-lid and free-surface configuration with topography are considered and compared with experiments.
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Trapped vortex"

1

Mishra, Debi Prasad, and PK Ezhil Kumar. "Trapped Vortex Combustor for Gas Turbine Application." In Advances in Combustion Technology, 145–81. Boca Raton: CRC Press, 2022. http://dx.doi.org/10.1201/9781003049005-7.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Che Idris, Azam, Mohd Rashdan Saad, and Mohd Rosdzimin Abdul Rahman. "Experimental Investigation of a Swirl Toroidal Trapped Vortex Miniature Combustor." In Lecture Notes in Mechanical Engineering, 15–23. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-3307-3_2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Donelli, R. S., F. De Gregorio, M. Buffoni, and O. Tutty. "Control of a trapped vortex in a thick airfoil by steady/unsteady mass flow suction." In Seventh IUTAM Symposium on Laminar-Turbulent Transition, 481–84. Dordrecht: Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-90-481-3723-7_80.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Sanpei, Akio, Kiyokazu Ito, Yukihiro Soga, Jun Aoki, and Yasuhito Kiwamoto. "Formation of a symmetric vortex configuration in a pure electron plasma trapped with a penning trap." In TCP 2006, 427–32. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-73466-6_53.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Li, Z., and J. H. P. Watson. "Trapped vortex magnetic separation (TVMS)." In Developments in Mineral Processing, C7–50—C7–56. Elsevier, 2000. http://dx.doi.org/10.1016/s0167-4528(00)80059-9.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Trapped vortex"

1

Garcia, Darwin, and Joseph Katz. "Trapped-Vortex in Ground Effect." In 32nd AIAA Fluid Dynamics Conference and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2002. http://dx.doi.org/10.2514/6.2002-3307.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Hsu, K., L. Gross, D. Trump, and W. Roquemore. "Performance of a trapped-vortex combustor." In 33rd Aerospace Sciences Meeting and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1995. http://dx.doi.org/10.2514/6.1995-810.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Katta, V., and W. Roquemore. "Numerical studies of trapped-vortex combustor." In 32nd Joint Propulsion Conference and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1996. http://dx.doi.org/10.2514/6.1996-2660.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Donelli, Raffaele, Fabrizio De Gregorio, and Pierluigi Iannelli. "Flow Separation Control By Trapped Vortex." In 48th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2010. http://dx.doi.org/10.2514/6.2010-1409.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Zhang, Chi, Yuzhen Lin, Quanhong Xu, and Gaoen Liu. "Investigation of Tangential Trapped Vortex Combustor." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59089.

Full text
Abstract:
An innovative concept of Tangential Trapped Vortex Combustor (TTVC) applying a swirling flow to eliminate the guide vanes of the compressor and turbine in the future gas turbine engines is presented via theoretical analysis and experimental investigation. In TTVC, the airflow is mostly whirlblast, and the processes of evaporation, mixing, and chemical reaction for the liquid spray combustion take place along the tangential direction. It is shown that the TTVC operation has the potential of improving combustion efficiency, widening combustion stability range, and reducing emissions, mainly due to the effects of trapped vortex, high centrifugal force, and periodical mixing. Experimental results of the ignition and LBO limits in a small 4-cup annular TTVC operating at atmospheric pressure demonstrated that this innovative combustion technology has a good LBO limit performance to meet the requirements of advanced gas turbine engines.
APA, Harvard, Vancouver, ISO, and other styles
6

Ardeshiri, H., and A. Afshari. "LES/FMDF of Trapped Vortex Combustors." In THMT-12. Proceedings of the Seventh International Symposium On Turbulence, Heat and Mass Transfer Palermo, Italy, 24-27 September, 2012. Connecticut: Begellhouse, 2012. http://dx.doi.org/10.1615/ichmt.2012.procsevintsympturbheattransfpal.2660.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Katta, Viswanath R., and William M. Roquemore. "Simulation of PAHs in Trapped-Vortex Combustor." In ASME Turbo Expo 2004: Power for Land, Sea, and Air. ASMEDC, 2004. http://dx.doi.org/10.1115/gt2004-54165.

Full text
Abstract:
Residence time and thermo-chemical environment are important factors in determining soot-formation characteristics of jet engine combustors. For understanding the chemical and physical structure of the soot formed in these combustors knowledge on flow dynamics and formation of polycyclic aromatics-hydrocarbons (PAHs) is required. A time-dependent, detailed-chemistry computational-fluid-dynamic (CFD) model is developed for the simulation of the reacting flows in a trapped-vortex combustor. The axisymmetric trapped-vortex combustor of Hsu et al. was modeled by replacing injection holes with injection slots. Ethylene-air mixtures were used as fuel. Several calculations were made by varying the equivalence ratio and velocity of the main flow. Unsteady simulations revealed that the shearlayer vortices established outside the cavity flow enhance mixing of benzene in the wake region of the afterbody. However, in all the cases considered here, majority of the PAH species are produced in the cavity region. While fuel-rich condition resulted lower amounts of PAHs in the cavity region, soot is produced more in this region.
APA, Harvard, Vancouver, ISO, and other styles
8

Mancilla, Paulo C., Pitchaiah Chakka, and Sumanta Acharya. "Performance of a Trapped Vortex Spray Combustor." In ASME Turbo Expo 2001: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/2001-gt-0058.

Full text
Abstract:
The performance of a liquid-fueled trapped vortex (TV) combustor is analyzed both experimentally and computationally. The TV cavity, formed between a forebody and an afterbody, is placed coaxially inside a combustor shell. Fuel and primary air are injected from the inside face of the afterbody. The flame holding capability of this trapped vortex configuration is evaluated for different primary equivalence ratios. Very low overall lean-blow-out (LBO) equivalence ratios are obtained for the TV combustor over a wide range of annular and primary airflow rates. It is found that by injecting the primary air with a tangential velocity component the circumferential mixing is improved without disrupting the vortex trapped in the cavity. The performance of the TV combustor is also evaluated through emissions measurements at the exit of the combustor and temperature distribution inside the cavity. Numerical simulations are performed for the TV configuration with a k-ε turbulence model coupled with a PDF combustion chemistry model for simulating liquid spray combustion. The predicted results are in reasonable agreement with the measurements and provide an assessment of the flow distribution in the cavity region.
APA, Harvard, Vancouver, ISO, and other styles
9

Briones, Alejandro M., and Balu Sekar. "Characteristics of Multi-Cavity Trapped Vortex Combustors." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-22151.

Full text
Abstract:
This research is motivated towards improving and optimizing the performance of AFRL’s Inter-Turbine Burner (ITB) in terms of greater combustion efficiency, reduced losses and exit temperature profile requirements. The ITB is a minicombustor concept, situated in between the high and low pressure turbine stages and typically contains multiple fueled and non-fueled Trapped Vortex Combustor (TVC) cavities. The size, placement, and arrangement of these cavities have tremendous effect on the combustor exit temperature profile. The detailed understanding of the effect of these cavities in a three-dimensional ITB configuration would be very difficult and computationally prohibited. Therefore, a simple but somewhat similar conceptual axi-symmetric burner is used here the design variations of Trapped Vortex Combustor (TVC) through modeling and simulation. The TVC can be one single cavity or can be represented by multi-cavity combustor. In this paper, both single cavity TVC and multi-cavity TVCs are studied. The single cavity TVC is divided into multiple cavities while the total volume of the combustor remains constant. Four combustors are studied: Baseline, Staged, Three-Staged, and Interdigitated TVC. An extensive computational investigation on the characteristics of these multi-cavity TVCs is presented. FLUENT is used for modeling the axisymmetric reacting flow past cavities using a global eddy dissipation mechanism for C3H8-air combustion with detailed thermodynamic and transport properties. Calculations are performed using Standard, RNG, and Realizable k-ε RANS turbulence models. The numerical results are validated against experimental temperature measurements on the Base TVC. Results indicate that the pressure drag is the major contributor to total drag in the Base TVC. However, viscous drag is still significant. By adding a concentric cavity in sequential manner (i.e. Staged TVC), the pressure drag decreases, whereas the viscous drag remains nearly constant. Further addition of a secondary concentric cavity (i.e. Three-Staged TVC), the total drag does not further decrease and both pressure and viscous drag contributions do not change. If instead a non-concentric cavity is added to the Base TVC (i.e. Interdigitated TVC), the pressure drag increases while the viscous drag decreases slightly. The effect of adding swirl flow is to increase the fuel-air mixing and as a result, it increases the maximum exit temperature for all the combustors modeled. The jets and heat release contribute to increase pressure drag with the former being greater. The fuel and air jets and heat release also modify the cavity flow structure. By turning off the fuel and air jets in the Staged TVC, lower drag (or pressure loss) and exit temperature are achieved. It is more effective to turn off the fuel and air jets in the upstream (front) cavity in order to reduce pressure losses. Based on these results, recommendations are provided to the engineer/designer/modeler to improve the performance of the ITB.
APA, Harvard, Vancouver, ISO, and other styles
10

Goldin, Graham M., Jens Madsen, Douglas L. Straub, William A. Rogers, and Kent H. Casleton. "Detailed Chemistry Simulations of a Trapped Vortex Combustor." In ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/gt2003-38780.

Full text
Abstract:
Steady simulations of a Trapped Vortex Combustor are performed with the Strained Laminar Flamelet model, the Eddy Dissipation Concept (EDC) model and the Composition PDF Transport model using an accurate 19 species Augmented Reduced Mechanism. CO predictions are reasonable, although the EDC model over-predicts CO since the reaction time in the fine scales is less than the residence time in the combustor. The PDF Transport model over-predicts NO by a factor of four for reasons that are not well understood at present. In-situ Adaptive Tabulation (ISAT) accelerates chemistry calculations by two to three orders of magnitude, making 3D CFD calculations with detailed chemistry computationally feasible.
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Trapped vortex"

1

Barlow, K., D. Burrus, E. Stevens, B. Duncan, S. Lamellar, and R. Boehm. Trapped Vortex Combustor Development for Military Aircraft. Fort Belvoir, VA: Defense Technical Information Center, January 2008. http://dx.doi.org/10.21236/ada478871.

Full text
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Trapped vortex' for particular source types:
Journal articles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography