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Letteratura scientifica selezionata sul tema "Jets"

Autore: Grafiati

Pubblicato: 4 giugno 2021

Ultima modifica: 29 luglio 2024

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Articoli di riviste sul tema "Jets"

1

Zhang, Yan-Jie, Qing-Min Zhang, Jun Dai, Zhe Xu e Hai-Sheng Ji. "Recurrent coronal jets observed by SDO/AIA". Research in Astronomy and Astrophysics 21, n. 10 (1 novembre 2021): 262. http://dx.doi.org/10.1088/1674-4527/21/10/262.

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Abstract In this paper, we carried out multiwavelength observations of three recurring jets on 2014 November 7. The jets originated from the same region at the edge of AR 12205 and propagated along the same coronal loop. The eruptions were generated by magnetic reconnection, which is evidenced by continuous magnetic cancellation at the jet base. The projected initial velocity of jet2 is ∼402 km s−1. The accelerations in the ascending and descending phases of jet2 are not consistent, the former is considerably larger than the value of g ⊙ at the solar surface, while the latter is lower than g ⊙. There are two possible candidates of extra forces acting on jet2 during its propagation. One is the downward gas pressure from jet1 when it falls back and meets with jet2. The other is the viscous drag from the surrounding plasma during the fast propagation of jet2. As a contrast, the accelerations of jet3 in the rising and falling phases are constant, implying that the propagation of jet3 is not significantly influenced by extra forces.

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2

Moore, Ronald L., Jonathan W. Cirtain, Alphonse C. Sterling e David A. Falconer. "DICHOTOMY OF SOLAR CORONAL JETS: STANDARD JETS AND BLOWOUT JETS". Astrophysical Journal 720, n. 1 (13 agosto 2010): 757–70. http://dx.doi.org/10.1088/0004-637x/720/1/757.

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3

Rhines, Peter B. "Jets". Chaos: An Interdisciplinary Journal of Nonlinear Science 4, n. 2 (giugno 1994): 313–39. http://dx.doi.org/10.1063/1.166011.

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4

Falle, S. A. E. G. "Jets". Astrophysics and Space Science 216, n. 1-2 (giugno 1994): 119–25. http://dx.doi.org/10.1007/bf00982478.

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5

Sterling, Alphonse C., Ronald L. Moore e Navdeep K. Panesar. "Another Look at Erupting Minifilaments at the Base of Solar X-Ray Polar Coronal “Standard” and “Blowout” Jets". Astrophysical Journal 927, n. 1 (1 marzo 2022): 127. http://dx.doi.org/10.3847/1538-4357/ac473f.

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Abstract We examine 21 solar polar coronal jets that we identify in soft X-ray images obtained from the Hinode/X-ray telescope (XRT). We identify 11 of these jets as blowout jets and four as standard jets, based on their X-ray-spire widths being respectively wide or narrow (compared to the jet’s base) in the XRT images. From corresponding extreme ultraviolet (EUV) images from the Solar Dynamics Observatory’s (SDO) Atmospheric Imaging Assembly (AIA), essentially all (at least 20 of 21) of the jets are made by minifilament eruptions, consistent with other recent studies. Here, we examine the detailed nature of the erupting minifilaments (EMFs) in the jet bases. Wide-spire (“blowout”) jets often have ejective EMFs, but sometimes they instead have an EMF that is mostly confined to the jet’s base rather than ejected. We also demonstrate that narrow-spire (“standard”) jets can have either a confined EMF, or a partially confined EMF where some of the cool minifilament leaks into the jet’s spire. Regarding EMF visibility: we find that in some cases the minifilament is apparent in as few as one of the four EUV channels we examined, being essentially invisible in the other channels; thus, it is necessary to examine images from multiple EUV channels before concluding that a jet does not have an EMF at its base. The sizes of the EMFs, measured projected against the sky and early in their eruption, is 14″ ± 7″, which is within a factor of 2 of other measured sizes of coronal-jet EMFs.

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6

Sterling, Alphonse C., Ronald L. Moore e Navdeep K. Panesar. "Solar Active Region Coronal Jets. III. Hidden-onset Jets". Astrophysical Journal 960, n. 2 (1 gennaio 2024): 109. http://dx.doi.org/10.3847/1538-4357/acff6b.

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Abstract Solar quiet- and coronal-hole region coronal jets frequently clearly originate from erupting minifilaments, but active-region jets often lack an obvious erupting-minifilament source. We observe a coronal-jet-productive active region (AR), AR 12824, over 2021 May 22 0–8 UT, primarily using Solar Dynamics Observatory (SDO) Atmospheric Imaging Array (AIA) EUV images and SDO/Helioseismic and Magnetic Imager magnetograms. Jets were concentrated in two locations in the AR: on the south side and on the northwest side of the AR’s lone large sunspot. The south-location jets are oriented so that we have a clear view of the jets’ origin low in the atmosphere: their source is clearly minifilaments erupting from locations showing magnetic flux changes/cancelations. After erupting a projected distance ≲5″ away from their origin site, the minifilaments erupt outward onto far-reaching field as part of the jet’s spire, quickly losing their minifilament character. In contrast, the northwest-location jets show no clear erupting minifilament, but the source site of those jets are obscured along our line of sight by absorbing chromospheric material. EUV and magnetic data indicate that the likely source sites were ≳15″ from where the we first see the jet spire; thus, an erupting minifilament would likely lose its minifilament character before we first see the spire. We conclude that such AR jets could work like non-AR jets, but the erupting-minifilament jet source is often hidden by obscuring material. Another factor is that magnetic eruptions making some AR jets carry only a harder-to-detect comparatively thin (∼1″–2″) minifilament “strand.”

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7

Plaschke, Ferdinand, e Heli Hietala. "Plasma flow patterns in and around magnetosheath jets". Annales Geophysicae 36, n. 3 (3 maggio 2018): 695–703. http://dx.doi.org/10.5194/angeo-36-695-2018.

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Abstract. The magnetosheath is commonly permeated by localized high-speed jets downstream of the quasi-parallel bow shock. These jets are much faster than the ambient magnetosheath plasma, thus raising the question of how that latter plasma reacts to incoming jets. We have performed a statistical analysis based on 662 cases of one THEMIS spacecraft observing a jet and another (second) THEMIS spacecraft providing context observations of nearby plasma to uncover the flow patterns in and around jets. The following results are found: along the jet's path, slower plasma is accelerated and pushed aside ahead of the fastest core jet plasma. Behind the jet core, plasma flows into the path to fill the wake. This evasive plasma motion affects the ambient magnetosheath, close to the jet's path. Diverging and converging plasma flows ahead and behind the jet are complemented by plasma flows opposite to the jet's propagation direction, in the vicinity of the jet. This vortical plasma motion results in a deceleration of ambient plasma when a jet passes nearby. Keywords. Magnetospheric physics (magnetosheath; MHD waves and instabilities; solar wind–magnetosphere interactions)

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8

Kimura, Motoaki, e Norimasa Miyagi. "STUDY ON DIFFUSION OF BUOYANT ROUND JETS(Jet and Plume)". Proceedings of the International Conference on Jets, Wakes and Separated Flows (ICJWSF) 2005 (2005): 413–18. http://dx.doi.org/10.1299/jsmeicjwsf.2005.413.

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9

Spencer, Ralph, Chris De La Force e Alastair Stirling. "Microquasar Jets: A Comparison with Extragalactic Jets". Symposium - International Astronomical Union 205 (2001): 264–65. http://dx.doi.org/10.1017/s0074180900221141.

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10

Denis, S., J. Delville, J.-H. Garem e J.-P. Bonnet. "Control of jets expansion by impeding jets". ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik 80, S1 (2000): 81–84. http://dx.doi.org/10.1002/zamm.20000801321.

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Tesi sul tema "Jets"

1

Pietroniro, Asuka Gabriele. "Modelling coaxial jets relevant to turbofan jet engines". Thesis, KTH, Mekanik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-200909.

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Simulations of subsonic turbulent coaxial hot jets were conducted on two types ofunstructured grids within the framework of STAR-CCM+. The study case is based on atypical airliner turbofan engine model with a core nozzle and a fan nozzle, having a bypassratio of five. The two meshes used are a polyhedral one, suitable for complex surfaces, and atrimmed one mainly made of hexahedral cells. The sensitivity of the study case to variousinputs is attested using second and third order upwind schemes, modelling turbulence with aSST k-omega model. The project proves to be a valid feasibility study for a steady-statesolution on which an aeroacoustic analysis could be based in future works.

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2

Pietroniro, Asuka Gabrielle. "Modelling coaxial jets relevat to turbofan jet engines". Thesis, KTH, Mekanik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-204020.

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Simulations of subsonic turbulent coaxial hot jets were conducted on two types ofunstructured grids within the framework of STAR-CCM+. The study case is based on atypical airliner turbofan engine model with a core nozzle and a fan nozzle, having a bypassratio of five. The two meshes used are a polyhedral one, suitable for complex surfaces, and atrimmed one mainly made of hexahedral cells. The sensitivity of the study case to variousinputs is attested using second and third order upwind schemes, modelling turbulence with aSST k-omega model. The project proves to be a valid feasibility study for a steady-statesolution on which an aeroacoustic analysis could be based in future works.
Simuleringar av subsoniska turbulenta koaxiala varma flöden genomfördes på två typer avostrukturerade nät inom ramen för STAR-CCM+. Studiefallet är baserat på en modell av enturbofläktmotor för ett typiskt trafikflygplan, med en inre samt yttre dysa och med ett bypassförhållandeav fem. De två beräkningsnät som används är ett polyedriskt nät, lämplig förkomplexa ytor, och ett trimmat nät huvudsakligen uppbyggt av sexsidiga celler. Känslighetenav studiefallet beroende på olika indata intygas med hjälp av andra och tredje ordningens”upwind-schemes”, där turbulensen modelleras med en SST k-omega modell. Projektet visarsig vara en giltig förstudie för en steadystate-lösning på vilken en aeroakustisk analys skullekunna baseras i framtida arbeten.

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3

Smith, Barton Lee. "Synthetic jets and their interaction with adjacent jets". Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/18889.

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4

Manfroi, Aldo J. "Zonal jets /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2001. http://wwwlib.umi.com/cr/ucsd/fullcit?p3035898.

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5

Moutoussi, Ann. "Quark and gluon jets in a three-jet environment". Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297244.

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6

Ghahremanian, Shahriar. "Near-Field Study of Multiple Interacting Jets : Confluent Jets". Doctoral thesis, Linköpings universitet, Energisystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-113259.

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This thesis deals with the near-field of confluent jets, which can be of interest in many engineering applications such as design of a ventilation supply device. The physical effect of interaction between multiple closely spaced jets is studied using experimental and numerical methods. The primary aim of this study is to explore a better understanding of flow and turbulence behavior of multiple interacting jets. The main goal is to gain an insight into the confluence of jets occurring in the near-field of multiple interacting jets. The array of multiple interacting jets is studied when they are placed on a flat and a curved surface. To obtain the boundary conditions at the nozzle exits of the confluent jets on a curved surface, the results of numerical prediction of a cylindrical air supply device using two turbulence models (realizable 𝑘 − 𝜖 and Reynolds stress model) are validated with hot-wire anemometry (HWA) near different nozzles discharge in the array. A single round jet is then studied to find the appropriate turbulence models for the prediction of the three-dimensional flow field and to gain an understanding of the effect of the boundary conditions predicted at the nozzle inlet. In comparison with HWA measurements, the turbulence models with low Reynolds correction (𝑘 − 𝜖 and shear stress transport [SST] 𝑘 − 𝜔) give reasonable flow predictions for the single round jet with the prescribed inlet boundary conditions, while the transition models (𝑘 − 𝑘l − 𝜔𝜔 and transition SST 𝑘 − 𝜔) are unable to predict the flow in the turbulent region. The results of numerical prediction (low Reynolds SST 𝑘 − 𝜔 model) using the prescribed inlet boundary conditions agree well with the HWA measurement in the nearfield of confluent jets on a curved surface, except in the merging region. Instantaneous velocity measurements are performed by laser Doppler anemometry (LDA) and particle image velocimetry (PIV) in two different configurations, a single row of parallel coplanar jets and an inline array of jets on a flat surface. The results of LDA and PIV are compared, which exhibit good agreement except near the nozzle exits. The streamwise velocity profile of the jets in the initial region shows a saddle back shape with attenuated turbulence in the core region and two off-centered narrow peaks. When confluent jets issue from an array of closely spaced nozzles, they may converge, merge, and combine after a certain distance downstream of the nozzle edge. The deflection plays a salient role for the multiple interacting jets (except in the single row configuration), where all the jets are converged towards the center of the array. The jet position, such as central, side and corner jets, significantly influences the development features of the jets, such as velocity decay and lateral displacement. The flow field of confluent jets exhibits asymmetrical distributions of Reynolds stresses around the axis of the jets and highly anisotropic turbulence. The velocity decays slower in the combined regio of confluent jets than a single jet. Using the response surface methodology, the correlations between characteristic points (merging and combined points) and the statistically significant terms of the three design factors (inlet velocity, spacing between the nozzles and diameter of the nozzles) are determined for the single row of coplanar parallel jets. The computational parametric study of the single row configuration shows that spacing has the greatest impact on the near-field characteristics.

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7

Stan, Gheorghe. "Fundamental Characteristics of Turbulent Opposed Impinging Jets". Thesis, University of Waterloo, 2000. http://hdl.handle.net/10012/831.

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A fundamental study of two turbulent directly opposed impinging jets in a stagnant ambient fluid, unconfined or uninfluenced by walls is presented. By experimental investigation and numerical modeling, the main characteristics of direct impingement of two turbulent axisymmetric round jets under seven different geometrical and flow rate configurations (L*= L/d = { 5, 10, 20 }, where L is nozzle to nozzle separation distance and d is nozzle diameter, and Re = { 1500, 4500, 7500, 11000 }) are discussed. Flow visualization and velocity measurements performed using various laser based techniques have revealed the effects of Reynolds number, Re, and nozzle to nozzle separation, L, on the complex flow structure. Although locally valid, the classical analysis of turbulence is found unable to provide reliable results within the highly unstable and unsteady impingement region. When used to simulate the present flow, the assessment of the performance of three distinct k - epsilon turbulence models showed little disagreement between computed and experimental mean velocities and poor predictions as far as turbulence parameters are concerned.

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8

Mutter, Troy Blake. "Numerical simulations of elliptical jets : a study of jet entrainment /". Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-07102009-040630/.

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9

Chakravorty, Saugata. "A Numerical Study On Absolute Instability Of Low Density Jets". Thesis, Indian Institute of Science, 2000. https://etd.iisc.ac.in/handle/2005/227.

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A spectacular instability has been observed in low density round jets when the density ratio of jet fluid to ambient fluid falls below a threshold of approximately 0.6. This phenomenon has been observed in non-buoyant jets of helium in air, heated air jets and heated buoyant jets. The oscillation of the flow near the nozzle is extremely regular and periodic and consists of ring vortices. Even the smaller scale structures that appear downstream exhibit similar regularity. A theory for predicting the onset of this oscillation is based on finding regions of absolute instability from linear stability analysis of parallel flow. However, experiments suggest that the theory is at least incomplete and fortuitous as the oscillation is not a linear process. The present work is to observe and understand the process of regeneration of these oscillations by conducting numerical simulations. Here, two-dimensional, plane jets were simulated because they undergo a qualitatively similar process. A spatial and temporal picture of a heated jet has been obtained numerically. A perturbation expansion was used to obtain a system of conservation laws for compressible flows which is valid for low Mach numbers. The low Mach number approximation removes the high frequency acoustic waves from the flow field. This enables a larger time step to be taken without making the calculation unstable. To ensure that all the scales of motion are properly resolved, calculations were done at a low Reynolds number. The governing equations were discretized in space using second-order finite difference formulas on a staggered grid. Velocity fields were advanced using a second-order Adams-Bashforth explicit scheme and then corrected by solving for pressure such that continuity is satisfied at every time step. The Poisson problem for pressure requires the time derivative of the density which was approximated by a third-order backward difference formula. Gauss-Siedel iteration was used to find the pressure. Several numerical tests were conducted prior to simulations of variable density jets to check the stability and accuracy of the code. Two dimensional driven cavity flow calculations were done as a first test. Then a calculation of a forced, spatially developing, incompressible, plane mixing layer was done to check the time accuracy of the code. After obtaining satisfactory performance of the code for the different test cases, two-dimensional, variable density jets were simulated. Since the plane jet extends ad infinitum in the streamwise direction, a sufficiently large domain was used to capture all the relevant physics in the downstream regions of the jet. An advective boundary condition was imposed at the exit plane. Rigid, slipwall conditions were employed to prescribe lateral boundary conditions. A 2-D, incompressible plane jet was simulated first. The jet profile was approximated by two hyperbolic tangent shear layers. The most unstable mode of the inviscid shear layer for this profile, along with its first and second harmonics, was imposed on the velocity profile at the inlet plane. The amplitude of oscillation of the harmonics was chosen so as to provide sufficient energy in the perturbation to accelerate the growth of the layer. No explicit phase lag was introduced in the perturbation. The flow was allowed to develop long enough to wash out the effect of the initial condition. The results obtained for this case indicate that experimentally realized phenomena such as vortex pairing were captured in this simulation. Furthermore, to check the convective nature of instability of the incompressible jet, the forcing at the inlet plane was turned off. The disturbances were gradually convected downstream, out of the computational domain. Next, two-dimensional heated, non-buoyant jets were studied numerically. The effects of the ratio of jet density to ambient density S, the velocity ratio R, and jet width W, on the near field behavior of an initial laminar jet and the regeneration mechanism of the self-sustaining vortices were explored. The theory based on domain of absolute/convective instability identifies these three parameters. No initial perturbation was necessary to start roll-up of the shear layer. For certain choices, e.g., S= 0.75, R = 20, W =10.5, self-sustaining oscillations appeared spontaneously, and these cycles repeated for very long simulation intervals. Waviness on the jet shear layers grow and roll-up into vortices as in constant density shear layers. But unlike the incompressible plane jet, these vortices grow much larger and mixes more with the surrounding fluid. As these vortices evolve, packets of fluid break away as trailing legs similar to side jet expulsions observed in round jets and plumes. The growing vortices disturb the upstream shear layer. Consistently with linear theory, which predicts absolute instability for these parameters, these disturbances are able to grow and roll up. If these disturbances travelled faster than the downstream vortices, it would not be possible for the cycle to repeat. With sufficient shear between the co-flowing streams (R not too small), the entire regeneration process was found to begin from roughly the same streamwise location. Furthermore, it is the symmetric, varicose mode which occurs. At a slightly larger density ratio (S = 0.8, R = 10), self-sustaining oscillations appeared, but each new cycle began slightly farther downstream. It seems likely that these values are close to the boundary in parameter space between self-sustained oscillatory and convectively unstable behaviors. Jet width also influences the selection of these two behaviors. When jet width was reduced, W = 6, even for S = 0.75,R = 20, each new cycle began to shift downstream. For larger jet width (W = 12.3), self-sustaining oscillations occur but the response is now as an asymmetric sinuous mode after a short initial varicose mode. The detailed processes that have now been revealed in plane jets should serve as guidelines for the study of such processes in the technologically more important round jets.

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10

Chakravorty, Saugata. "A Numerical Study On Absolute Instability Of Low Density Jets". Thesis, Indian Institute of Science, 2000. http://hdl.handle.net/2005/227.

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Abstract (sommario):

A spectacular instability has been observed in low density round jets when the density ratio of jet fluid to ambient fluid falls below a threshold of approximately 0.6. This phenomenon has been observed in non-buoyant jets of helium in air, heated air jets and heated buoyant jets. The oscillation of the flow near the nozzle is extremely regular and periodic and consists of ring vortices. Even the smaller scale structures that appear downstream exhibit similar regularity. A theory for predicting the onset of this oscillation is based on finding regions of absolute instability from linear stability analysis of parallel flow. However, experiments suggest that the theory is at least incomplete and fortuitous as the oscillation is not a linear process. The present work is to observe and understand the process of regeneration of these oscillations by conducting numerical simulations. Here, two-dimensional, plane jets were simulated because they undergo a qualitatively similar process. A spatial and temporal picture of a heated jet has been obtained numerically. A perturbation expansion was used to obtain a system of conservation laws for compressible flows which is valid for low Mach numbers. The low Mach number approximation removes the high frequency acoustic waves from the flow field. This enables a larger time step to be taken without making the calculation unstable. To ensure that all the scales of motion are properly resolved, calculations were done at a low Reynolds number. The governing equations were discretized in space using second-order finite difference formulas on a staggered grid. Velocity fields were advanced using a second-order Adams-Bashforth explicit scheme and then corrected by solving for pressure such that continuity is satisfied at every time step. The Poisson problem for pressure requires the time derivative of the density which was approximated by a third-order backward difference formula. Gauss-Siedel iteration was used to find the pressure. Several numerical tests were conducted prior to simulations of variable density jets to check the stability and accuracy of the code. Two dimensional driven cavity flow calculations were done as a first test. Then a calculation of a forced, spatially developing, incompressible, plane mixing layer was done to check the time accuracy of the code. After obtaining satisfactory performance of the code for the different test cases, two-dimensional, variable density jets were simulated. Since the plane jet extends ad infinitum in the streamwise direction, a sufficiently large domain was used to capture all the relevant physics in the downstream regions of the jet. An advective boundary condition was imposed at the exit plane. Rigid, slipwall conditions were employed to prescribe lateral boundary conditions. A 2-D, incompressible plane jet was simulated first. The jet profile was approximated by two hyperbolic tangent shear layers. The most unstable mode of the inviscid shear layer for this profile, along with its first and second harmonics, was imposed on the velocity profile at the inlet plane. The amplitude of oscillation of the harmonics was chosen so as to provide sufficient energy in the perturbation to accelerate the growth of the layer. No explicit phase lag was introduced in the perturbation. The flow was allowed to develop long enough to wash out the effect of the initial condition. The results obtained for this case indicate that experimentally realized phenomena such as vortex pairing were captured in this simulation. Furthermore, to check the convective nature of instability of the incompressible jet, the forcing at the inlet plane was turned off. The disturbances were gradually convected downstream, out of the computational domain. Next, two-dimensional heated, non-buoyant jets were studied numerically. The effects of the ratio of jet density to ambient density S, the velocity ratio R, and jet width W, on the near field behavior of an initial laminar jet and the regeneration mechanism of the self-sustaining vortices were explored. The theory based on domain of absolute/convective instability identifies these three parameters. No initial perturbation was necessary to start roll-up of the shear layer. For certain choices, e.g., S= 0.75, R = 20, W =10.5, self-sustaining oscillations appeared spontaneously, and these cycles repeated for very long simulation intervals. Waviness on the jet shear layers grow and roll-up into vortices as in constant density shear layers. But unlike the incompressible plane jet, these vortices grow much larger and mixes more with the surrounding fluid. As these vortices evolve, packets of fluid break away as trailing legs similar to side jet expulsions observed in round jets and plumes. The growing vortices disturb the upstream shear layer. Consistently with linear theory, which predicts absolute instability for these parameters, these disturbances are able to grow and roll up. If these disturbances travelled faster than the downstream vortices, it would not be possible for the cycle to repeat. With sufficient shear between the co-flowing streams (R not too small), the entire regeneration process was found to begin from roughly the same streamwise location. Furthermore, it is the symmetric, varicose mode which occurs. At a slightly larger density ratio (S = 0.8, R = 10), self-sustaining oscillations appeared, but each new cycle began slightly farther downstream. It seems likely that these values are close to the boundary in parameter space between self-sustained oscillatory and convectively unstable behaviors. Jet width also influences the selection of these two behaviors. When jet width was reduced, W = 6, even for S = 0.75,R = 20, each new cycle began to shift downstream. For larger jet width (W = 12.3), self-sustaining oscillations occur but the response is now as an asymmetric sinuous mode after a short initial varicose mode. The detailed processes that have now been revealed in plane jets should serve as guidelines for the study of such processes in the technologically more important round jets.

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Più fonti

Libri sul tema "Jets"

1

Brad, Vinson, e De Angel Miguel, a cura di. J-E-T-S Jets! Jets! Jets! Chantilly, VA: Mascot Books, 2008.

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2

Jefferis, David. Jets. London: Belitha, 2000.

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3

Jenssen, Hans. Jets. New York, N.Y: DK PUb., 1996.

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4

Riggs, Kate. Jets. Mankato, MN: Creative Education, 2010.

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5

Szurovy, Geza. Executive jets. Osceola, WI: MBI Publishing Co., 1998.

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6

Phillips, Almarin, A. Paul Phillips e Thomas R. Phillips. Biz Jets. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-0812-6.

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7

Dennis, Baldry, Berg, Gerrit Jan van den e Vertaalbureau van den Berg, a cura di. Super jets. Helmond: Helmond, 1992.

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8

Bodden, Valerie. Fighter jets. Mankato, MN: Creative Paperbacks, 2012.

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9

House, Beekman. Fighting jets. New York, N.Y: Beekman House, 1990.

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10

Finn, Denny Von. Supersonic jets. Minneapolis, MN: Bellwether Media, 2010.

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Più fonti

Capitoli di libri sul tema "Jets"

1

Marzani, Simone, Gregory Soyez e Michael Spannowsky. "Jets and Jet Algorithms". In Lecture Notes in Physics, 23–34. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-15709-8_3.

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2

Falle, S. A. E. G. "Jets". In Kinematics and Dynamics of Diffuse Astrophysical Media, 119–25. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-0926-0_18.

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3

Romero, Gustavo E., e Gabriela S. Vila. "Jets". In Introduction to Black Hole Astrophysics, 161–222. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-39596-3_5.

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4

Livio, Mario. "Astrophysical Jets". In Protostellar Jets in Context, 3–9. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-00576-3_1.

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5

Yershin, Shakhbaz A. "Coaxial Jets". In Paradoxes in Aerohydrodynamics, 257–74. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-25673-3_10.

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6

Tesař, V. "Impinging Jets". In Fluid Mechanics and Its Applications, 191–231. Singapore: Springer Singapore, 2015. http://dx.doi.org/10.1007/978-981-287-396-5_6.

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Mohseni, Kamran. "Microsynthetic Jets". In Encyclopedia of Microfluidics and Nanofluidics, 2225–31. New York, NY: Springer New York, 2015. http://dx.doi.org/10.1007/978-1-4614-5491-5_1018.

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Jirka, G. H. "Shallow Jets". In Recent Research Advances in the Fluid Mechanics of Turbulent Jets and Plumes, 155–75. Dordrecht: Springer Netherlands, 1994. http://dx.doi.org/10.1007/978-94-011-0918-5_10.

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9

Kundt, W. "The Jets". In Astrophysical Jets and Their Engines, 21–28. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3927-1_3.

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Drew, Edward. "Tidal Jets". In Encyclopedia of Modern Coral Reefs, 1091–92. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-90-481-2639-2_259.

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Atti di convegni sul tema "Jets"

1

Rappoccio, Salvatore, e CMS Collaboration. "Jets and jet substructure". In 19TH PARTICLES AND NUCLEI INTERNATIONAL CONFERENCE (PANIC11). AIP, 2012. http://dx.doi.org/10.1063/1.3700689.

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2

Pavlova, Anna A., e Michael Amitay. "Electronic Cooling Using Synthetic Jets". In ASME 2005 Summer Heat Transfer Conference collocated with the ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems. ASMEDC, 2005. http://dx.doi.org/10.1115/ht2005-72110.

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Abstract (sommario):

Efficiency of synthetic jet impingement cooling and the mechanisms of heat removal from a constant heat flux surface were investigated experimentally. The effects of jet’s formation frequency and Reynolds number at different nozzle-to-surface distances were investigated and compared to steady jet cooling. It was found that synthetic jets are up to three times more effective than steady jets at the same Reynolds number. For smaller distances, high formation frequency (f = 1200 Hz) synthetic jets remove heat better than low frequency (f = 420 Hz) jets, whereas low frequency jets are more effective at larger distances, with an overlapping region. Using PIV, it was shown that at small distances between the synthetic jet and the heated surface, the higher formation frequency jet is associated with accumulation of vortices before they impinge on the surface. For the lower frequency jet, the wavelength between coherent structures is so large that vortex rings impinge on the surface separately.

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Gilinsky, M., J. Seiner, B. Jansen e T. Bhat. "Supersonic gasdispersional jets and jet noise". In 15th Aeroacoustics Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1993. http://dx.doi.org/10.2514/6.1993-4389.

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4

Theirich, D., J. Kedzierski e J. Engemann. "Atmospherich pressure plasma jets: Concepts and realization of miniaturized jets and jet arrays". In 2008 IEEE 35th International Conference on Plasma Science (ICOPS). IEEE, 2008. http://dx.doi.org/10.1109/plasma.2008.4590623.

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5

"Jets". In CONV-09. Proceedings of International Symposium on Convective Heat and Mass Transfer in Sustainable Energy. Connecticut: Begellhouse, 2009. http://dx.doi.org/10.1615/ichmt.2009.conv.360.

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ENGLERT, Christoph, Erik Gerwick, Tilman Plehn, Peter Schichtel e Steffen Schumann. "W/Z plus jets/multi-jets". In XXIst International Europhysics Conference on High Energy Physics. Trieste, Italy: Sissa Medialab, 2012. http://dx.doi.org/10.22323/1.134.0238.

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Edgington-Mitchell, Daniel M., e Petrônio A. Nogueira. "The guided-jet mode in compressible jets". In AIAA AVIATION 2023 Forum. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2023. http://dx.doi.org/10.2514/6.2023-3647.

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Voutilainen, Mikko. "Results on inclusive jets and jet properties". In Proceedings of the XVI International Workshop on Deep-Inelastic Scattering and Related Topics. Amsterdam: Science Wise Publishing, 2008. http://dx.doi.org/10.3360/dis.2008.176.

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9

Page, Brian. "Jets and Jet Substructure at an EIC". In XXVII International Workshop on Deep-Inelastic Scattering and Related Subjects. Trieste, Italy: Sissa Medialab, 2019. http://dx.doi.org/10.22323/1.352.0232.

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Fidalgo Rodríguez, Guillermo. "New Trigger Studies for Emerging Jets at CMS Experiment". In New Trigger Studies for Emerging Jets at CMS Experiment. US DOE, 2023. http://dx.doi.org/10.2172/1988436.

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Rapporti di organizzazioni sul tema "Jets"

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Wibowo, Johannes, e Jamie López-Soto. Field Jet Erosion Tests on Benbrook Dam, Texas. Engineer Research and Development Center (U.S.), dicembre 2021. http://dx.doi.org/10.21079/11681/42545.

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Abstract (sommario):

This report summarizes the results of eight field Jet Erosion Tests (JETs) performed on Benbrook Dam, TX. The results from these tests will be used by the U.S. Army Corps of Engineers, Fort Worth District, in assessments of the erosion resistance of the Benbrook Dam with regards to possible overtopping by extreme flooding. The JETs were performed at four different locations, i.e., two locations at the lowest crest elevation and two locations at the mid-slope face of the downstream embankment. Variations in estimated critical hydraulic shear stress and erosion rate values may have been caused by differences in soil composition, i.e., when the material changed from silt/sand to clay. The resulting values of the Erodibility Coefficient, Kd, and Critical Stress, τc, are very useful information in assessing the stability of Benbrook Dam during an overtopping event. Because of the observed natural variability of the materials, combining the erosion parameters presented in this report with the drilling logs and local geology will be imperative for assessing erosion-related failure modes of Benbrook Dam.

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2

Fasel, Hermann F. Numerical Simulations of Wall Jets. Fort Belvoir, VA: Defense Technical Information Center, luglio 1997. http://dx.doi.org/10.21236/ada329611.

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Pease, Leonard F., Judith A. Bamberger e Michael J. Minette. Implications of Upwells as Hydrodynamic Jets in a Pulse Jet Mixed System. Office of Scientific and Technical Information (OSTI), agosto 2015. http://dx.doi.org/10.2172/1233489.

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Pease, Leonard F., Judith A. Bamberger e Michael J. Minette. Implications of Upwells as Hydrodynamic Jets in a Pulse Jet Mixed System. Office of Scientific and Technical Information (OSTI), febbraio 2017. http://dx.doi.org/10.2172/1357719.

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Zeda, Jason D. Numerical Simulation of Evaporating Capillary Jets. Fort Belvoir, VA: Defense Technical Information Center, agosto 1999. http://dx.doi.org/10.21236/ada367314.

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Alon, Raz. Substructure of Highly Boosted Massive Jets. Office of Scientific and Technical Information (OSTI), ottobre 2012. http://dx.doi.org/10.2172/1352045.

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7

Wu, J. M., A. D. Vakili e F. M. Yu. Investigation of Non-Symmetric Jets in Cross Flow (Discrete Wing Tip Jet Effects). Fort Belvoir, VA: Defense Technical Information Center, dicembre 1986. http://dx.doi.org/10.21236/ada179783.

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Jeffrey B. Parker and John A. Krommes. Zonal Flow as Pattern Formation: Merging Jets and the Ultimate Jet Length Scale. Office of Scientific and Technical Information (OSTI), gennaio 2013. http://dx.doi.org/10.2172/1062392.

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9

Gomon, M. Experimental study of highly viscous impinging jets. Office of Scientific and Technical Information (OSTI), dicembre 1998. http://dx.doi.org/10.2172/296715.

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10

Saif, A. A. Numerical calculation of two-phase turbulent jets. Office of Scientific and Technical Information (OSTI), maggio 1995. http://dx.doi.org/10.2172/90229.

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