Relevant bibliographies by topics / Self-interacting fields

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Self-interacting fields'

Author: Grafiati
Published: 4 June 2021
Last updated: 13 February 2022

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

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Self-interacting fields.'

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 "Self-interacting fields"

1

TALEBAOUI, WATHEK. "THEORY OF SELF-INTERACTING SCALAR FIELDS AND GRAVITATION." Modern Physics Letters A 08, no. 22 (July 20, 1993): 2053–60. http://dx.doi.org/10.1142/s0217732393001768.

Full text
Abstract:
The theory of self-interacting scalar fields and gravitation is discussed using Robertson-Walker metric in conformal time. The theory is formulated in terms of a metric compatible connection with torsion. Analytic solutions are derived and in some cases we make explicit contact with the conventional Brans-Dicke theory.
APA, Harvard, Vancouver, ISO, and other styles
2

Jäde, L., and H. V. von Geramb. "Nonlinear approach toNNinteractions using self-interacting meson fields." Physical Review C 55, no. 1 (January 1, 1997): 57–66. http://dx.doi.org/10.1103/physrevc.55.57.

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

Mahmoodzadeh, A., and B. Malekolkalami. "Oscillatons described by self-interacting quartic scalar fields." Physics of the Dark Universe 19 (March 2018): 21–26. http://dx.doi.org/10.1016/j.dark.2017.11.001.

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

Jetzer, Philippe. "Gravitational equilibria of self-interacting charged scalar fields." Nuclear Physics B - Proceedings Supplements 16 (August 1990): 653–55. http://dx.doi.org/10.1016/0920-5632(90)90628-8.

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

Lee, Cheng-Yang. "Self-interacting mass-dimension one fields for any spin." International Journal of Modern Physics A 30, no. 11 (April 16, 2015): 1550048. http://dx.doi.org/10.1142/s0217751x15500487.

Full text
Abstract:
According to Ahluwalia and Grumiller, massive spin-half fields of mass-dimension one can be constructed using the eigenspinors of the charge-conjugation operator (Elko) as expansion coefficients. In this paper, we generalize their result by constructing quantum fields from higher-spin Elko. The kinematics of these fields are thoroughly investigated. Starting with the field operators, their propagators and Hamiltonians are derived. These fields satisfy the higher-spin generalization of the Klein–Gordon but not the Dirac equation. Independent of the spin, they are all of mass-dimension one and are thus endowed with renormalizable self-interactions. These fields violate Lorentz symmetry. The violation can be characterized by a non-Lorentz-covariant term that appears in the Elko spin-sums. This term provides a decomposition of the generalized higher-spin Dirac operator in the momentum space thus suggesting a possible connection between the mass-dimension one fields and the Lorentz-invariant fields.
APA, Harvard, Vancouver, ISO, and other styles
6

Colpi, Monica, Stuart L. Shapiro, and Ira Wasserman. "Boson Stars: Gravitational Equilibria of Self-Interacting Scalar Fields." Physical Review Letters 57, no. 20 (November 17, 1986): 2485–88. http://dx.doi.org/10.1103/physrevlett.57.2485.

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

Saha, Bijan. "Interacting self-consistent system of spinor and gravitational fields." International Journal of Modern Physics A 35, no. 02n03 (January 30, 2020): 2040047. http://dx.doi.org/10.1142/s0217751x20400473.

Full text
Abstract:
Within the scope of simple cosmological models we have studied the role of spinor field in the evolution of the Universe when it is non-minimally coupled to the gravitational one. If the spinor field nonlinearity describes an ordinary matter such as radiation, the presence of non-minimality becomes essential and leads to the rapid expansion of the Universe in FRW model, but this is not the case for LRSBI model. If the spinor field nonlinearity describes a dark energy the role non-minimal coupling becomes insignificant in both isotropic and anisotropic models.
APA, Harvard, Vancouver, ISO, and other styles
8

Shiraishi, K., and S. Hirenzaki. "Quantum aspects of self-interacting fields around cosmic strings." Classical and Quantum Gravity 9, no. 10 (October 1, 1992): 2277–86. http://dx.doi.org/10.1088/0264-9381/9/10/011.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Gunzig, Edgar, Pascal Nardone, and Norbert Van Den Bergh. "Self-interacting scalar fields on a conformally flat background." Physics Letters B 238, no. 2-4 (April 1990): 262–64. http://dx.doi.org/10.1016/0370-2693(90)91733-r.

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

Barone, F. A., and M. Hott. "Self-energies for interacting fields with a compactified spatial dimension." Brazilian Journal of Physics 38, no. 2 (June 2008): 210–18. http://dx.doi.org/10.1590/s0103-97332008000200002.

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

Dissertations / Theses on the topic "Self-interacting fields"

1

Yun, Gunsu Soonshin Bellan Paul Murray Bellan Paul Murray. "Dynamics of plasma structures interacting with external and self-generated magnetic fields /." Diss., Pasadena, Calif. : California Institute of Technology, 2008. http://resolver.caltech.edu/CaltechETD:etd-07242007-162442.

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

Collini, Giovanni. "Fedosov Quantization and Perturbative Quantum Field Theory." Doctoral thesis, Universitätsbibliothek Leipzig, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-224698.

Full text
Abstract:
Fedosov has described a geometro-algebraic method to construct in a canonical way a deformation of the Poisson algebra associated with a finite-dimensional symplectic manifold (\\\"phase space\\\"). His algorithm gives a non-commutative, but associative, product (a so-called \\\"star-product\\\") between smooth phase space functions parameterized by Planck\\\'s constant ℏ, which is treated as a deformation parameter. In the limit as ℏ goes to zero, the star product commutator goes to ℏ times the Poisson bracket, so in this sense his method provides a quantization of the algebra of classical observables. In this work, we develop a generalization of Fedosov\\\'s method which applies to the infinite-dimensional symplectic \\\"manifolds\\\" that occur in Lagrangian field theories. We show that the procedure remains mathematically well-defined, and we explain the relationship of this method to more standard perturbative quantization schemes in quantum field theory.
APA, Harvard, Vancouver, ISO, and other styles
3

Yun, Gunsu Soonshin. "Dynamics of plasma structures interacting with external and self-generated magnetic fields." Thesis, 2008. https://thesis.library.caltech.edu/2979/2/Yun-Gunsu_2008_embedded.pdf.

Full text
Abstract:
Plasmas interacting with external and self-generated magnetic fields often develop a long tubular structure of nearly uniform cross section. Such long collimated plasma tubes have been observed in a variety of contexts ranging from astrophysical plasma jets (1015–1022 m) to solar coronal loops (107–108 m). Remarkably, much smaller-sized plasmas (0.1–1 m) produced by the Caltech planar spheromak gun develop collimated structures bearing a striking resemblance to these natural plasma tubes. This thesis presents experimental observations of gun-produced plasma tubes that support a recently-proposed magnetohydrodynamic (MHD) pumping model as a universal collimation mechanism. For any flared flux tube carrying a finite axial current, the model predicts (i) magnetic pumping of plasma particles from a constricted region into a bulged region and (ii) tube collimation if the flow slows down at the bulged region, leading to accumulation of mass and thus concentrating the azimuthal magnetic flux frozen in the mass flow (i.e., increasing the pinch force). Time- and space-resolved spectroscopic measurements of gun-produced plasmas show (i) suprathermal Alfvenic flow (30–50 km/s), (ii) large density amplification from ~1017 to ~1022 m-3 in an Alfvenic time scale (5–10 µs), and (iii) flow slowing down and mass accumulation at the flow front, the place where the tube collimation occurs according to high-speed camera imaging. These observations are consistent with the predictions of the MHD pumping model, and thus the model offers valuable insight into the formation mechanism of laboratory, solar, and astrophysical plasma structures.
APA, Harvard, Vancouver, ISO, and other styles
4

Collini, Giovanni. "Fedosov Quantization and Perturbative Quantum Field Theory." Doctoral thesis, 2016. https://ul.qucosa.de/id/qucosa%3A15631.

Full text
Abstract:
Fedosov has described a geometro-algebraic method to construct in a canonical way a deformation of the Poisson algebra associated with a finite-dimensional symplectic manifold (\\\"phase space\\\"). His algorithm gives a non-commutative, but associative, product (a so-called \\\"star-product\\\") between smooth phase space functions parameterized by Planck\\\''s constant ℏ, which is treated as a deformation parameter. In the limit as ℏ goes to zero, the star product commutator goes to ℏ times the Poisson bracket, so in this sense his method provides a quantization of the algebra of classical observables. In this work, we develop a generalization of Fedosov\\\''s method which applies to the infinite-dimensional symplectic \\\"manifolds\\\" that occur in Lagrangian field theories. We show that the procedure remains mathematically well-defined, and we explain the relationship of this method to more standard perturbative quantization schemes in quantum field theory.
APA, Harvard, Vancouver, ISO, and other styles
5

Binder, Tobias. "Refining the chemical and kinetic decoupling description of thermally produced dark matter." Doctoral thesis, 2019. http://hdl.handle.net/11858/00-1735-0000-002E-E5E9-2.

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

Books on the topic "Self-interacting fields"

1

Cardaliaguet, Pierre, François Delarue, Jean-Michel Lasry, and Pierre-Louis Lions. The Master Equation and the Convergence Problem in Mean Field Games. Princeton University Press, 2019. http://dx.doi.org/10.23943/princeton/9780691190716.001.0001.

Full text
Abstract:
This book describes the latest advances in the theory of mean field games, which are optimal control problems with a continuum of players, each of them interacting with the whole statistical distribution of a population. While it originated in economics, this theory now has applications in areas as diverse as mathematical finance, crowd phenomena, epidemiology, and cybersecurity. Because mean field games concern the interactions of infinitely many players in an optimal control framework, one expects them to appear as the limit for Nash equilibria of differential games with finitely many players as the number of players tends to infinity. The book rigorously establishes this convergence, which has been an open problem until now. The limit of the system associated with differential games with finitely many players is described by the so-called master equation, a nonlocal transport equation in the space of measures. After defining a suitable notion of differentiability in the space of measures, the authors provide a complete self-contained analysis of the master equation. Their analysis includes the case of common noise problems in which all the players are affected by a common Brownian motion. They then go on to explain how to use the master equation to prove the mean field limit. The book presents two important new results in mean field games that contribute to a unified theoretical framework for this exciting and fast-developing area of mathematics.
APA, Harvard, Vancouver, ISO, and other styles
2

Thurner, Stefan, Rudolf Hanel, and Peter Klimekl. Networks. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198821939.003.0004.

Full text
Abstract:
Understanding the interactions between the components of a system is key to understanding it. In complex systems, interactions are usually not uniform, not isotropic and not homogeneous: each interaction can be specific between elements.Networks are a tool for keeping track of who is interacting with whom, at what strength, when, and in what way. Networks are essential for understanding of the co-evolution and phase diagrams of complex systems. Here we provide a self-contained introduction to the field of network science. We introduce ways of representing and handle networks mathematically and introduce the basic vocabulary and definitions. The notions of random- and complex networks are reviewed as well as the notions of small world networks, simple preferentially grown networks, community detection, and generalized multilayer networks.
APA, Harvard, Vancouver, ISO, and other styles
3

Horing, Norman J. Morgenstern. Equations of Motion with Particle–Particle Interactions and Approximations. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198791942.003.0008.

Full text
Abstract:
Starting with the equation of motion for the field operator ψ(x,t) of an interacting many-particle system, the n-particle Green’s function (Gn) equation of motion is developed, with interparticle interactions generating an infinite chain of equations coupling it to (n+1)- and (n−1)-particle Green’s functions (Gn+1 and Gn−1, respectively). Particularly important are the one-particle Green’s function equation with its coupling to the two-particle Green’s function and the two-particle Green’s function equation with its coupling to the three-particle Green’s function. To develop solutions, it is necessary to introduce non-correlation decoupling procedures involving the Hartree and Hartree-Fock approximations for G2 in the G1 equation; and a similar factorization “ansatz” for G3 in the G2 equation, resulting in the Sum of Ladder Diagrams integral equation for G2, with multiple Born iterates and finite collisional lifetimes. Similar treatment of the G11-equation for the joint propagation of one-electron and one-hole subject to mutual Coulomb attraction leads to bound electron-hole exciton states having a discrete hydrogen like spectrum of energy eigenstates. Its role in single-particle propagation is also discussed in terms of one-electron self-energy Σ‎ and the T-matrix
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Self-interacting fields"

1

Suzuki, Takashi. "Self-interacting Fluids." In Mean Field Theories and Dual Variation - Mathematical Structures of the Mesoscopic Model, 203–45. Paris: Atlantis Press, 2015. http://dx.doi.org/10.2991/978-94-6239-154-3_7.

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

Metral, E., G. Rumolo, and W. Herr. "Impedance and Collective Effects." In Particle Physics Reference Library, 105–81. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-34245-6_4.

Full text
Abstract:
AbstractAs the beam intensity increases, the beam can no longer be considered as a collection of non-interacting single particles: in addition to the “single-particle phenomena”, “collective effects” become significant. At low intensity a beam of charged particles moves around an accelerator under the Lorentz force produced by the “external” electromagnetic fields (from the guiding and focusing magnets, RF cavities, etc.). However, the charged particles also interact with themselves (leading to space charge effects) and with their environment, inducing charges and currents in the surrounding structures, which create electromagnetic fields called wake fields. In the ultra-relativistic limit, causality dictates that there can be no electromagnetic field in front of the beam, which explains the term “wake”. It is often useful to examine the frequency content of the wake field (a time domain quantity) by performing a Fourier transformation on it. This leads to the concept of impedance (a frequency domain quantity), which is a complex function of frequency. The charged particles can also interact with other charged particles present in the accelerator (leading to two-stream effects, and in particular to electron cloud effects in positron/hadron machines) and with the counter-rotating beam in a collider (leading to beam–beam effects). As the beam intensity increases, all these “perturbations” should be properly quantified and the motion of the charged particles will eventually still be governed by the Lorentz force but using the total electromagnetic fields, which are the sum of the external and perturbation fields. Note that in some cases a perturbative treatment is not sufficient and the problem has to be solved self consistently. These perturbations can lead to both incoherent (i.e. of a single particle) and coherent (i.e. of the centre of mass) effects, in the longitudinal and in one or both transverse directions, leading to beam quality degradation or even partial or total beam losses. Fortunately, stabilising mechanisms exist, such as Landau damping, electronic feedback systems and linear coupling between the transverse planes (as in the case of a transverse coherent instability, one plane is usually more critical than the other).
APA, Harvard, Vancouver, ISO, and other styles
3

Galstian, Anahit, and Karen Yagdjian. "The Self-interacting Scalar Field Propagating in FLRW Model of the Contracting Universe." In Trends in Mathematics, 315–23. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-04459-6_30.

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

ROMANS, L. J. "SELF-DUALITY FOR INTERACTING FIELDS: Covariant field equations for six-dimensional chiral supergravities." In Supergravities in Diverse Dimensions, 393–414. World Scientific Publishing Company, 1989. http://dx.doi.org/10.1142/9789814542340_0028.

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

"Self-interacting scalar field theory." In Lectures on Quantum Field Theory, 213–58. WORLD SCIENTIFIC, 2020. http://dx.doi.org/10.1142/9789811220876_0006.

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

"Self-interacting scalar field theory." In Lectures on Quantum Field Theory, 211–55. WORLD SCIENTIFIC, 2008. http://dx.doi.org/10.1142/9789812832870_0006.

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

"SELF INTERACTING BOSONIC QUANTUM FIELD." In Structural Aspects of Quantum Field Theory and Noncommutative Geometry, 621–64. WORLD SCIENTIFIC, 2013. http://dx.doi.org/10.1142/9789814472708_0025.

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

"SELF INTERACTING BOSONIC QUANTUM FIELD." In Structural Aspects of Quantum Field Theory and Noncommutative Geometry, 625–67. 2nd ed. WORLD SCIENTIFIC, 2021. http://dx.doi.org/10.1142/9789811237089_0025.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

"Self-interacting Fermionic Models." In Non-Perturbative Methods in 2 Dimensional Quantum Field Theory, 127–54. WORLD SCIENTIFIC, 2001. http://dx.doi.org/10.1142/9789812810151_0005.

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

Zinn-Justin, Jean. "Gross–Neveu–Yukawa and Gross–Neveu models." In Quantum Field Theory and Critical Phenomena, 489–506. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198834625.003.0020.

Full text
Abstract:
In this chapter, a model is considered that can be defined in continuous dimensions, the Gross– Neveu–Yukawa (GNY) model, which involves N Dirac fermions and one scalar field. The model has a continuous U(N) symmetry, and a discrete symmetry, which prevents the addition of a fermion mass term to the action. For a specific value of a coefficient of the action, the model undergoes a continuous phase transition. The broken phase illustrates a mechanism of spontaneous symmetry breaking, leading to spontaneous fermion mass generation like in the Standard Model (SM) of particle physics. In four dimensions, the GNY can be considered as a toy model to represent the interactions between the top quark and the Higgs boson, the heaviest particles of the SM of fundamental interactions, when the gauge fields are omitted. The model is renormalizable in four dimensions and its renormalization group (RG) properties can be studied in d = 4 and d = 4 − ϵ dimensions. A model of self-interacting fermions with the same symmetries and fermion content, the Gross–Neveu (GN) model, has been widely studied. In perturbation theory, for d > 2, it describes only a phase with massless fermions but, in d = 2 + ϵ dimensions, the RG indicates that, at a critical value of the coupling constant, the model experiences a phase transition. In two dimensions, it is renormalizable and exhibits the phenomenon of asymptotic freedom. The massless phase becomes infrared unstable and there is strong evidence that the spectrum corresponds to spontaneous symmetry breaking and fermion mass generation.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Self-interacting fields"

1

Ho, Jen, Andrew Keenlyside, Jake Sieradzki, Su Hua Sim, and Mark Hughes. "Validating a novel visual field assessment app: A pilot study." In VIRTUAL ACADEMIC SURGERY CONFERENCE 2021. Cambridge Medicine Journal, 2021. http://dx.doi.org/10.7244/cmj.2021.04.001.4.

Full text
Abstract:
Introduction The paper Cullen chart has been a validated adjunct to perimeters in detecting scotomas for various neuro-ophthalmological pathologies for decades. It was digitized into a prototype-app to empower future users to conduct remote monitoring of visual fields. This project aimed to refine the apps' usability for future users to self-assess and monitor their visual fields by exploring the difficulties faced using the app, to gather feedback, and subsequently to improve its usability for future iterations to objectively compare iterations using the MAUQ scores. Methods Participants (n = 15; age: 24-58) recruited through convenience sampling underwent mixed (quantitative and qualitative) methods to measure 1. Participants' adherence to the app instruction through observation, 2. objective experiences of using the app through self-reporting using the mHealth App Usability Questionnaire (MAUQ), and 3. Subjective experience of app using through semi-structured interviews. Descriptive analysis was computed for observation and MAUQ data. Thematic analysis was adopted to analyse the semi-structured interview data. Results 1/15 adhered to 3 written instructions and 8/15 participants had awkward hand movements. The MAUQ median score was 123/147, the MAUQ domain mean scores - ease of use and satisfaction, system information arrangement and usefulness were 81.6%(45.7/56), 80.6%(33.9/42) and 80.2%(39.3/49), respectively. Questions 4, 5, 9, 11 and 19 were the 5 lowest-scoring questions. Qualitative data were categorised into instructions, test, and feedback which had codes and subcodes. Conclusion Feedback for improvements were surrounding central fixation, remembering peripheral stimuli, uncover eye when interacting with peripheral stimuli, video examples, an introduction to the app and audio instructions.
APA, Harvard, Vancouver, ISO, and other styles
2

Briscese, F., Luis Arturo Ureña-López, Hugo Aurelio Morales-Técotl, Román Linares-Romero, Elí Santos-Rodríguez, and Sendic Estrada-Jiménez. "Self-interacting complex scalar field as dark matter." In VIII WORKSHOP OF THE GRAVITATION AND MATHEMATICAL PHYSICS DIVISION OF THE MEXICAN PHYSICAL SOCIETY. AIP, 2011. http://dx.doi.org/10.1063/1.3647543.

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

García Aspeitia, Miguel A., Juan Aldebarán Magaña, Tonatiuh Matos, Pablo A. Rodriguez, H. A. Morales-Tecotl, L. A. Urena-Lopez, R. Linares-Romero, and H. H. Garcia-Compean. "Primordial Perturbations Produced by a Self Interacting Scalar Field in the Braneworld: The Dynamical Systems Perspective." In GRAVITATIONAL PHYSICS: TESTING GRAVITY FROM SUBMILLIMETER TO COSMIC: Proceedings of the VIII Mexican School on Gravitation and Mathematical Physics. AIP, 2010. http://dx.doi.org/10.1063/1.3473865.

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

Rutili, Samuel. "Properties of the thermal two-point functions in curved spacetimes for a self-interacting scalar field." In Proceedings of the MG14 Meeting on General Relativity. WORLD SCIENTIFIC, 2017. http://dx.doi.org/10.1142/9789813226609_0499.

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

Duarte, D. C., R. L. Farias, and Rudnei O. Ramos. "Non-perturbative description of self-interacting charged scalar field at finite temperature and in the presence of an external magnetic field." In XII HADRON PHYSICS. AIP, 2013. http://dx.doi.org/10.1063/1.4795995.

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

Geng, Shaojuan, Hongwu Zhang, Jingyi Chen, and Weiguang Huang. "Numerical Study on the Response of Tip Leakage Flow Unsteadiness to Micro Tip Injection in a Low-Speed Isolated Compressor Rotor." In ASME Turbo Expo 2007: Power for Land, Sea, and Air. ASMEDC, 2007. http://dx.doi.org/10.1115/gt2007-27729.

Full text
Abstract:
A numerical study on the unsteady tip leakage flow with discrete micro tip injection from casing shroud in a low-speed isolated axial compressor rotor is presented. The main target is to clarify the flow mechanism of how the stall control measures act on the tip leakage flow typified by its self-induced unsteady flow characteristics. At operating condition near stall point, a series of calculations have been carried out for different axial position of injector and different injected mass flow rate. The computation results of flow field near rotor tip region show that under the influence of injected flow, the transient pressure distribution fluctuates along blade chord on both pressure and suction sides with respect to the relative position of injector and rotor. The pressure difference across the pressure and suction sides of compressor blade changes correspondingly, thus introduces a forced flow unsteadiness interacting with the unsteady tip leakage flow. When the injection is relatively strong and able to meet the tip leakage flow at its origination, the self-induced unsteadiness of tip leakage flow can be suppressed completely. In most cases, both frequency components of the self-induced unsteadiness and forced-induced unsteadiness are co-existing. The corresponding transient flow contours show that a local high pressure spot appears near blade pressure side, which moves downstream and shifts the tip leakage flow trajectory with less or without touching the neighboring pressure surface of the blade. Based on this understanding of discrete tip injection as force-induced flow unsteadiness, the numerical results are also analyzed to optimize the effect of injection in changing the route of tip leakage flow trajectories and therefore the chance of stability improvement of the compressor rotor.
APA, Harvard, Vancouver, ISO, and other styles
7

Ramachandran, Gopakumar, Ankit Kumar Dutta, Harish Durairaj, and Swetaprovo Chaudhuri. "On the Interaction of Swirling Flames in a Lean Premixed Combustor." In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-90679.

Full text
Abstract:
Abstract Premixed or partially premixed swirling flames are widely used in gas turbine applications because of their compactness, high ignition efficiency, low NOx emissions and flame stability. A typical annular combustor consists of about eighteen to twenty-two swirling flames which interact (directly or indirectly) with their immediate neighbors even during stable operation. These interactions significantly alter the flow and flame topologies thereby bringing in some discrepancies between the single nozzle (SN) and multi nozzle (MN), ignition, emission, pattern factor and Flame Transfer Functions (FTF) characteristics. For example, in MN configurations, application of a model based on SN FTF data could lead to erroneous conclusions. Due to the complexities involved in this problem in terms of size, thermal power, cost, optical accessibility etc., a limited amount of experimental studies has been reported, that too on scaled down models with reduced number of nozzles. Here, we present a detailed experimental study on the behavior of three interacting swirl premixed flames, arranged in-line in an optically accessible hollow cuboid test section, which closely resembles a three-cup sector of an annular gas turbine combustor with very large radius. Multiple configurations with various combinations of swirl levels between the adjacent nozzles and the associated flame and flow topologies have been studied. Spatio-temporal information of the heat release rate obtained from OH* chemiluminescence imaging was used along with the acoustic pressure signatures to compute the Rayleigh index so as to identify the regions within the flame that pumps energy into the self-excited thermoacoustic instability modes. It was found that the structure of the flame-flame interaction regions plays a dominant role in the resulting thermoacoustic instability. To resolve the flow and reactive species field distributions in the interacting flames, two-dimensional, three component Stereoscopic Particle Image Velocimetry (SPIV) and Planar Laser Induced Fluorescence (PLIF) of hydroxyl radical was applied to all the test conditions. Significant differences in the flow structures among the different configurations were observed. Simultaneous OH-PLIF and SPIV techniques were also utilized to track the flame front, from which the curvature and stretch rates were computed. Flame surface density which is defined as the mean surface area of the reaction zone per unit volume is also computed for all the test cases. These measurements and analyses elucidate the structure of the interaction regions, their unique characteristics and possible role in thermoacoustic instability.
APA, Harvard, Vancouver, ISO, and other styles
8

Stapp, Dennis, and Peter F. Pelz. "Evolution of Swirl Boundary Layer and Wall Stall at Part Load: A Generic Experiment." In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-26235.

Full text
Abstract:
The influence of Reynolds number, roughness and turbulence on the onset of wall stall is up to now not sufficiently understood. To shed some light onto the interdependency of near wall flow with growing swirl component, the simplest “machine” is tested. The apparatus we examine is a circular pipe at rest followed by a rotating co-axial pipe segment. In the sense of a generic experiment this machine represents a very basic model of the inlet of an axial machine. Due to the wall shear stress a swirl boundary layer is formed in the rotating pipe segment, interacting with the axial boundary layer. The evolution of the swirl velocity profile with increasing axial distance from the rotating pipe inlet is measured for various Reynolds numbers, flow numbers and degrees of turbulence by means of Laser Doppler Anemometry. We observe a self-similarity in the swirl velocity profile, for subcritical flow number and develop a scaling law for the velocity distribution in the transition section of a rotating pipe. At critical flow number the boundary layer is separating, resulting in a ring vortex at the inlet of the rotating pipe. Our work fills the gap of previous experimental works, with respect to high Reynolds numbers and low flow numbers. The parameter field we examine is most relevant for turbomachinery application and wall stall. In addition our boundary layer resolution is sufficient to resolve the swirl boundary layer thickness. Only this high resolution enables us to generalize the experimental findings by means of a similarity distribution of the velocity profile within the swirl boundary layer.
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Self-interacting fields' 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