Academic literature on the topic 'Resonant over-reflection'
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Journal articles on the topic "Resonant over-reflection"
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Benilov, E. S., and V. N. Lapin. "On resonant over-reflection of waves by jets." Geophysical & Astrophysical Fluid Dynamics 107, no. 3 (June 2013): 304–27. http://dx.doi.org/10.1080/03091929.2012.709515.
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Xu, Wei, Chun Chen, Min Han Htet, Mohammad Saydul Islam Sarkar, Aifeng Tao, Zhen Wang, Jun Fan, and Degang Jiang. "Experimental Investigation on Bragg Resonant Reflection of Waves by Porous Submerged Breakwaters on a Horizontal Seabed." Water 14, no. 17 (August 29, 2022): 2682. http://dx.doi.org/10.3390/w14172682.
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Submerged breakwaters based on Bragg resonance could be one of the measures used for mitigating marine disasters and coastal erosion in nearshore areas. Here, flume experiments were conducted to investigate the Bragg resonant reflection of waves propagating over porous submerged breakwaters. Furthermore, the influence of permeability, relative width, relative height, and section shapes of submerged breakwaters on Bragg resonant reflection were considered. This revealed that the Bragg resonant reflection coefficient increased with the decrease in permeability and increase in the relative height of submerged breakwaters. However, a slowing trend occurred when the Bragg resonant reflection coefficient peak decreased with the increase in permeability and increased with the increase in relative height. Moreover, the primary peak Bragg resonance increased with the increase in the relative width of submerged breakwaters in the range of 0.1–0.3. This was consistent with the numerical results of Ni and Teng (2021), to a certain extent, as the reflection coefficient first increased and then decreased with the relative bar width. In addition, rectangular submerged breakwaters demonstrated a better reflection effect than the trapezoidal submerged breakwaters, and the triangular submerged breakwaters demonstrated a poor reflection effect.
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Dragna, Didier, Ariane Emmanuelli, Sébastien Ollivier, and Philippe Blanc-Benon. "Sonic boom reflection over urban areas." Journal of the Acoustical Society of America 152, no. 6 (December 2022): 3323–39. http://dx.doi.org/10.1121/10.0016442.
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Sonic boom propagation over urban areas is studied using numerical simulations based on the Euler equations. Two boom waves are examined: a classical N-wave and a low-boom wave. Ten urban geometries, generated from the local climate zone classification [Stewart and Oke (2012), Bull. Am. Meteorol. Soc. 93(12), 1879–1900], are considered representative of urban forms. They are sorted into two classes, according to the aspect ratio of urban canyons. For compact geometries with a large aspect ratio, the noise levels and the peak pressure, especially for the N-wave, are highly variable between canyons. For open geometries with a small aspect ratio, these parameters present the same evolution in each urban canyon, corresponding to that obtained for isolated buildings. A statistical analysis of the noise levels in urban canyons is then performed. For both boom waves, the median of the perceived noise levels mostly differs by less than 1 dB from the value obtained for flat ground. The range of variation is greater for open geometries than for compact ones. Finally, low-frequency oscillations, associated with resonant modes of the canyons, are present for both compact and open geometries. Their amplitude, frequency and decay rate vary greatly from one canyon to another.
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Xiong, Lei, Hongwei Ding, Yuanfu Lu, and Guangyuan Li. "Active tuning of resonant lattice Kerker effect." Journal of Physics D: Applied Physics 55, no. 18 (February 10, 2022): 185106. http://dx.doi.org/10.1088/1361-6463/ac4ec5.
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Abstract The Kerker effect has been generalized in nanophotonics and meta-optics, and has recently been of great interest by relating it to various fascinating functionalities such as scattering management and perfect transmission, reflection or absorption. One of the most interesting generalizations is the resonant lattice Kerker effect in periodic nanostructures. However, its active tuning has not been explored yet. Here, we report, for the first time, the active control of the resonant lattice Kerker effect in periodic Ge2Se2Te5 nanodisks. By changing the crystalline fraction, we show that the electric dipole surface lattice resonance (ED-SLR), the magnetic dipole resonance (MDR), and thus the resonant lattice Kerker effect are all red-shifted. We therefore realize the transition from the ED-SLR to the resonant lattice Kerker effect, which enables multilevel tuning of reflection, transmission and absorption with modulation depths above 86%. Taking advantage of the MDR redshifts, we also observe broadband and multilevel tuning of transmissions with modulation depth of 87% over a broadband range of 588 nm. Our work establishes a new path for designing high-performance active nanophotonic devices.
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Mei, Chiang C. "Resonant reflection of surface water waves by periodic sandbars." Journal of Fluid Mechanics 152 (March 1985): 315–35. http://dx.doi.org/10.1017/s0022112085000714.
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One of the possible mechanisms of forming offshore sandbars parallel to a coast is the wave-induced mass transport in the boundary layer near the sea bottom. For this mechanism to be effective, sufficient reflection must be present so that the waves are partially standing. The main part of this paper is to explain a theory that strong reflection can be induced by the sandbars themselves, once the so-called Bragg resonance condition is met. For constant mean depth and simple harmonic waves this resonance has been studied by Davies (1982), whose theory, is however, limited to weak reflection and fails at resonance. Comparison of the strong reflection theory with Heathershaw's (1982) experiments is made. Furthermore, if the incident waves are slightly detuned or slowly modulated in time, the scattering process is found to depend critically on whether the modulational frequency lies above or below a threshold frequency. The effects of mean beach slope are also studied. In addition, it is found for periodically modulated wave groups that nonlinear effects can radiate long waves over the bars far beyond the reach of the short waves themselves. Finally it is argued that the breakpoint bar of ordinary size formed by plunging breakers can provide enough reflection to initiate the first few bars, thereby setting the stage for resonant reflection for more bars.
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Lee, Jun-Whan, Koo-Yong Park, and Yong-Sik Cho. "Shear Current Effects on Monochromatic Water Waves Crossing Trenches." Journal of Applied Mathematics 2015 (2015): 1–11. http://dx.doi.org/10.1155/2015/256084.
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The reflection coefficients of monochromatic water waves over trenches with shear current are estimated analytically. The diffraction of waves by an abrupt depth change and shear current is formulated by the matched eigenfunction expansion method. The proper number of steps and evanescent modes are proposed by a series of convergence tests. The accuracy of the predicted reflection coefficients is checked by estimating the wave energy. Reflection and transmission characteristics are studied for various shear current conditions. The different combinations of strength, width of shear current, and incident wave angle with constant water depth topography are examined. The optimal figure of the trench with shear current is obtained by estimating the reflection coefficients for various sloped transitions. The resonant reflection of the water waves is found by multiarrayed optimal trenches and the interaction of sinusoidally varying topography with shear current.
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Decker, M., T. Pertsch, and I. Staude. "Strong coupling in hybrid metal–dielectric nanoresonators." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375, no. 2090 (March 28, 2017): 20160312. http://dx.doi.org/10.1098/rsta.2016.0312.
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We study resonant photonic–plasmonic coupling between a gold dipole nanoantenna and a silicon nanodisc supporting electric and magnetic dipolar Mie-type resonances. Specifically, we consider two different cases for the mode structure of the silicon nanodisc, namely spectrally separate and spectrally matching electric and magnetic dipolar Mie-type resonances. In the latter case, the dielectric nanoparticle scatters the far fields of a unidirectional Huygens’ source. Our results reveal an anticrossing of the plasmonic dipole resonance and the magnetic Mie-type dipole resonance of the silicon nanodisc, accompanied by a clear signature of photonic–plasmonic mode hybridization in the corresponding mode profiles. These characteristics show that strong coupling is established between the two different resonant systems in the hybrid nanostructure. Furthermore, our results demonstrate that in comparison with purely metallic or dielectric nanostructures, hybrid metal–dielectric nanoresonators offer higher flexibility in tailoring the fractions of light which are transmitted, absorbed and reflected by the nanostructure over a broad range of parameters without changing its material composition. As a special case, highly asymmetric reflection and absorption properties can be achieved. This article is part of the themed issue ‘New horizons for nanophotonics’.
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Zagitova, Azaliya Azatovna, Andrey Sergeevich Zhuravlev, Leonid Viktorovich Kulik, and Vladimir Umansky. "Spin Transport in a Quantum Hall Insulator." Applied Sciences 11, no. 17 (September 1, 2021): 8131. http://dx.doi.org/10.3390/app11178131.
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A novel experimental optical method, based on photoluminescence and photo-induced resonant reflection techniques, is used to investigate the spin transport over long distances in a new, recently discovered collective state—magnetofermionic condensate. The given Bose–Einstein condensate exists in a purely fermionic system (ν = 2 quantum Hall insulator) due to the presence of a non-equilibrium ensemble of spin-triplet magnetoexcitons—composite bosons. It is found that the condensate can spread over macroscopically long distances of approximately 200 μm. The propagation velocity of long-lived spin excitations is measured to be 25 m/s.
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Belibassakis, Kostas, Julien Touboul, Elodie Laffitte, and Vincent Rey. "A Mild-Slope System for Bragg Scattering of Water Waves by Sinusoidal Bathymetry in the Presence of Vertically Sheared Currents." Journal of Marine Science and Engineering 7, no. 1 (January 7, 2019): 9. http://dx.doi.org/10.3390/jmse7010009.
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Extended mild-slope models (MMSs) are examined for predicting the characteristics of normally incident waves propagating over sinusoidal bottom topography in the presence of opposing shearing currents. It is shown that MMSs are able to provide quite good predictions in the case of Bragg scattering of waves over rippled bathymetry without a current, but fail to provide good predictions concerning the resonant frequency in the additional presence of a current. In order to resolve the above mismatch, a two-equation mild-slope system (CMS2) is derived from a variational principle based on the representation of the wave potential expressed as a superposition of the forward and backward components. The latter system is compared against experimentally measured data collected in a wave flume and is shown to provide more accurate predictions concerning both the resonant frequency and the amplitude of the reflection coefficient. Future work will be devoted to the examination of the derived model for a more general wave system over realistic seabed topography.
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Rotshild, David, and Amir Abramovich. "Ultra-Wideband Reconfigurable X-Band and Ku-Band Metasurface Beam-Steerable Reflector for Satellite Communications." Electronics 10, no. 17 (September 4, 2021): 2165. http://dx.doi.org/10.3390/electronics10172165.
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A continuously reconfigurable metasurface reflector based on unit cell mushroom geometry that was integrated with a varactor diode is presented in this paper. The unit cell of the metasurface was designed and optimized to operate in the X-band and Ku-band, improving satellite communication’s quality of service. The losses mechanisms of continuous control over the unit cell phase reflection in beam steering resolution are considered and the analysis results are presented. The unit cell design parameters were analyzed with an emphasis on losses and dynamic reflection phase range. The unit cell magnitude and phase reflection are shown in the wide frequency bandwidth and showed a good agreement between all the measurements and the simulations. This metasurface enabled a high dynamic range in the unit cell resonant frequency range from 7.8 to 15 GHz. In addition, the reflection phase and absorption calibration are demonstrated for multiple operating frequencies, namely, 11 GHz, 12 GHz, and 13.5 GHz. Furthermore, design trade-offs and manufacturing limitations were considered. Finally, a beam-steering simulation using the designed metasurface is shown and discussed.
Books on the topic "Resonant over-reflection"
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Manning, Susan, and Lucia Ruprecht. Introduction. University of Illinois Press, 2017. http://dx.doi.org/10.5406/illinois/9780252036767.003.0001.
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This introductory chapter first sets out the book's purpose, which is to offer fresh histories and theoretical inquiries that will resonate not only for scholars working in the field of dance, but also for scholars working on literature, film, visual culture, theater, and performance. It then sketches the intellectual and artistic trends over the last thirty years that have shaped the scholarship featured in New German Dance Studies. It follows the broadly chronological organization of the volume as a whole: opening essays on theater dance before 1900; then research clusters on Weimar dance, dance in the German Democratic Republic, and conceptual dance; and a closing reflection on the circulation of dance in an era of globalization. Throughout it emphasizes the complex interplay between dance-making and dance writing, as well as interrelations between dance practice and research and artistic and intellectual trends in German culture at large.
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Podder, Sukanya. Peacebuilding Legacy. Oxford University PressOxford, 2022. http://dx.doi.org/10.1093/oso/9780192863980.001.0001.
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Abstract A fundamental challenge plagues the global peacebuilding community. How can technocratic approaches to peacebuilding that are rooted in short-term, project-based execution of activities further the longer-term transformative outcomes like altering young people’s attitudes and beliefs about peace and violence? In response to this global challenge, in Peacebuilding Legacies, Sukanya Podder addresses an important gap relating to the long-term effects of peacebuilding programmes involving children and young people. Podder unpacks the concept of peacebuilding legacy through the lens of time, transformation, and intergenerational peace. Podder also develops unique qualitative cues for measuring legacy in terms of the institutional, normative, and organizational logics. If norms resonate strongly with the local context, they are likely to encourage strong retention and meaningful adoption over time. Successful institutionalization of project models through planned handover to successor national organizations or government departments holds the key to stronger local ownership. Organizational learning and reflection can support this process through a more strategic approach to programming and through post-exit studies. With regard to attitude change, Podder found that the media and peace education projects that targeted individuals’ ingrained beliefs and values but overlooked the role of group social norms had only limited persuasive effects. To shift the values, practices, norms, and beliefs of the younger generation, the mindset of the older generation must also be targeted. Changes in the legal, political, economic, and other social institutions are critical for long-term and meaningful transformation. This requires adopting an ecological model of peace.
Book chapters on the topic "Resonant over-reflection"
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Podder, Sukanya. "Peacebuilding Legacy." In Peacebuilding Legacy, 24–51. Oxford University PressOxford, 2022. http://dx.doi.org/10.1093/oso/9780192863980.003.0002.
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Abstract This chapter explains the book’s theoretical underpinnings. It begins by unpacking the concept of peacebuilding legacy through the lens of time, transformation, and intergenerational peace. Legacy is captured through three qualitative cues around norm transmission, resonance, and retention; institutionalization and adaptation of project models; and organizational learning and reflection from monitoring and evaluation (M&E). The analytical framework anticipates that high norm resonance will elicit high compliance and high retention of external norms over the longer term. Neutral resonance will prompt non-participation and mixed retention, while low resonance will encourage non-compliance, resistance, and rejection, leading to weak retention. Commitment to institutionalization through the formal adoption of externally funded project models by successor organizations will support knowledge transfer, while enhancing local ownership. Finally, the long-term monitoring of outcomes beyond project life-cycles would require a conscious commitment to learning and reflection; and further investments in preserving the institutional memory and in post-closure evaluations.
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Dailey, Alice. "Postscript." In How to Do Things with Dead People, 174–80. Cornell University Press, 2022. http://dx.doi.org/10.7591/cornell/9781501763656.003.0007.
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This postscript focuses on David Bowie, considering the many possible paths that are suggested but not taken by this book—paths through music, memoir, film, television, dramatic adaptation, and countless other media and art forms that resonate with the history plays' engagement with the dead. Like Richard II's meditation on his corpse, Bowie's reflection on his dead self reproduces him through forms that transcend the deathbed. Even as he constructs his dead self, Bowie is generating afterdeaths, which resonate with those of Andy Warhol, Richard II, Falstaff's Lazaran conscripts, Richard III, and many of the other figures who inhabit this book. “Lazarus” is the title of not only a song from Blackstar but Bowie's late-career musical, which was in its debut off-Broadway run when he died, his artistic creation restaged and replayed again and again even as his body was cremated and his ashes scattered over Bali. As a musician, performer, virtuoso of camp, actor, painter, art collector, denizen of the past, Starman of the future, and as a writer, Bowie hovers at the site of disciplinary and temporal crossings this book explores.
Conference papers on the topic "Resonant over-reflection"
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Nouman, Muhammad Tayyab, Ji Hyun Hwang, Kye Jeong Lee, Celso Leite, Do-Kyeong Ko, and Jae-Hyung Jang. "Designing over and under coupled resonant metamaterial cavities to control reflection mode optical phase characteristics (Conference Presentation)." In Metamaterials, Metadevices, and Metasystems 2018, edited by Nader Engheta, Mikhail A. Noginov, and Nikolay I. Zheludev. SPIE, 2018. http://dx.doi.org/10.1117/12.2323173.
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Hsu, Tai-Wen, Shan-Hwei Ou, Chin-Yen Tsai, and Jian-Feng Lin. "Kinetic, Dynamic and Energy Characteristics of Vortex Evolution on Bragg Scattering of Water Waves." In ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/omae2010-21092.
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The vortex generation and dissipation under Bragg scattering of water wave propagation over a series of submerged rectangular breakwaters are investigated both numerically and experimentally. A Reynolds Averaged Navier-Stokes (RANS) model combined with a k–ε turbulence closure is applied to simulate the entire vortex evolution process as water waves pass over a series of artificial rectangular bars. The Particle Image Velocimetry (PIV) is also used to measure the velocity field in the vicinity of the obstacles. The numerical model is validated through the comparisons of water surface elevations and velocity field with the measurements. The mechanism of vortex evolution and its influence on the interaction of water waves with submerged structures for both cases of resonance and non-resonance were studied. Wave reflection coefficients for both resonant and non-resonant cases were calculated and compared with experiments and solutions based on the linear wave theory. It is also found that the calculated vortex intensity at the last bar is only one third of that at the leading bar for the near-resonant case. The local kinetic energy is also found to attain its minimum value at a place where potential energy became larger in Bragg scattering of water waves.
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Tatel, Gerard, and Xiaoyi Bao. "Microsphere coupled off-core fiber sensor for ultrasound sensing." In Optical Fiber Sensors. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/ofs.2022.w4.70.
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A compact fiber ultrasound-sensing device comprised of a Barium Titanate (BaTiO3) microsphere coupled to an open cavity off-core Fabry-Perot (FP) fiber sensor fabricated through lateral offset splicing single mode fiber (SMF-28) is proposed and demonstrated. The multiple passes of the FPI enabled by the high refractive index microsphere brought a 40dB enhancement of finesse. The broadband ultrasound sensing over 0.1- 45 MHz is achieved by selecting whispering gallery modes (WGMs) via varying microsphere position. The scattering and internal reflection of light in the microsphere is enabled by multibeam interference, leading to an increase in passages and WGMs at specific resonant wavelengths, and hence the high contrast and quality factor of the transmission spectrum are obtained for broadband ultrasound detection at high sensitivity. The optimized lateral offset is governed by the diameter of the microsphere to maximize the frequency response of the acoustic wave of a piezoelectric transducer centered at 3.7 MHz.
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Shepherd, Joseph E. "Structural Response of Piping to Internal Gas Detonation." In ASME 2006 Pressure Vessels and Piping/ICPVT-11 Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/pvp2006-icpvt-11-93670.
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Detonation waves in gas-filled piping or tubing pose special challenges in analysis and prediction of structural response. The challenges arise due the nature of the detonation process and the role of fluid-structure interaction in determining the propagation and arrest of fractures. Over the past ten years, our laboratory has been engaged in studying this problem and developing methodologies for estimating structural response. A brief overview of detonation waves and some key issues relevant to structural waves is presented first. This is followed by a summary of our work on the elastic response of tubes and pipes to ideal detonation loading, highlighting the importance of detonation wave speed in determining flexural wave excitation and possibility of resonant response leading to large deformations. Some issues in measurement technique and validation testing are then presented. The importance of wave reflection from bends, valves and dead ends is discussed, as well as the differences between detonation, shock wave, and uniform internal pressure loading. Following this, we summarize our experimental findings on the fracture threshold of thin-walled tubes with pre-existing flaws. A particularly important issue for hazard analysis is the estimation of loads associated with flame acceleration and deflagration-to-detonation transition. We give some recent results on pressure and elastic strain measurements in the transition regime for a thick-wall piping, and some remarks about plastic deformation.
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Grigoriev, Mikhail, and James Hitt. "Non-Periodic 3D Diffusers for Mitigating Aerodynamic Exciters." In ASME 2014 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/detc2014-34295.
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The great majority of the modern centrifugal stages utilize periodic stationary structures such as inlet guide vanes and/or diffuser vanes. To maximize the aerodynamic performance of the centrifugal stage, these vanes must be positioned at a close proximity of the centrifugal impeller. This arrangement results in a dramatic interaction between rotating impeller and stationary vanes due to reflection of the pressure waves from the periodic vanes back onto the impeller blades. The periodic nature of the reflected pressure waves may lead to an excitation of the impeller blade eigenmodes if the fundamental frequency (or, its multiple) of the external force matches with the natural frequency of the subject impeller. As the impeller blades provide very little to no damping, there is a strong possibility of the high cycle fatigue resonance failure of the impeller blades if the impeller design does not provide with a sufficient separation from the resonance modes. We should note that ensuring such a separation is not straightforward task for many stages with periodic exciters, and may not be even feasible for some practical design cases. This presentation focuses on a novel way to mitigate possible resonance issues for centrifugal impellers due to pressure reflection waves emanating from the diffuser blades. We propose to utilize non-periodic centrifugal diffuser together with the sculpting leading edges for the three-dimensional diffuser vanes. In order to demonstrate the attractiveness and feasibility of this approach, we have utilized Computational Fluid Dynamics (CFD) tools to perform time-accurate unsteady turbulent flow analyses in centrifugal stages and capture cyclic pressure waves acting on the impeller blades. The present work considers a regular periodic low-solidity diffuser with two-dimensional vanes, a three-dimensional periodic diffuser with a sculpted leading edge, and, finally, a non-periodic three-dimensional diffuser with an unequal, non-repeating stagger. We have utilized eighteen CFD pressure probes located on the impeller blade pressure and suction sides to monitor temporal variations of the static pressure that capture the pressure reflection waves from the diffuser vanes. The Fourier series decomposition facilitates detailed analyses of the pressure energy distribution over a wide range of frequencies. The results of the numerical studies demonstrate that even the use of the periodic diffuser with 3D sculpted leading edges help reduce the magnitude of the pressure oscillations at the dominant frequency and its integer multiples. However, the pressure energy distribution changes dramatically when using the non-periodic diffuser arrangement together with the sculpted leading edge vanes. The strength of the pressure waves associated with the dominant harmonics and its integer multiples are reduced about 30% to 85% and spread over the frequencies that constitute integer multiples of the fundamental impeller frequency. This pressure energy redistribution of the 3D non-periodic diffuser is a significant aid to the aerodynamicist. By significantly reducing the mechanical constraint compromises, the designer is allowed to focus more on aerodynamic component efficiency.
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Arzoumanian, Sevag, and Nigel Peake. "Fluid Structure Interaction With Mean Flow: Over-Scattering and Unstable Resonance Growth." In ASME 2010 3rd Joint US-European Fluids Engineering Summer Meeting collocated with 8th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2010. http://dx.doi.org/10.1115/fedsm-icnmm2010-31170.
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It is known theoretically [1–3] that infinitely long fluid loaded plates in mean flow exhibit a range of unusual phenomena in the ‘long time’ limit. These include convective instability, absolute instability and negative energy waves which are destabilized by dissipation. However, structures are necessarily of finite length and may have discontinuities. Moreover, linear instability waves can only grow over a limited number of cycles before non-linear effects become dominant. We have undertaken an analytical and computational study to investigate the response of finite, discontinuous plates to ascertain if these unusual effects might be realized in practice. Analytically, we take a “wave scattering” [2,4] — as opposed to a “modal superposition” [5] — view of the fluttering plate problem. First, we solve for the scattering coefficients of localized plate discontinuities and identify a range of parameter space, well outside the convective instability regime, where over-scattering or amplified reflection/transmission occurs. These are scattering processes that draw energy from the mean flow into the plate. Next, we use the Wiener-Hopf technique to solve for the scattering coefficients from the leading and trailing edges of a baffled plate. Finally, we construct the response of a finite, baffled plate by a superposition of infinite plate propagating waves continuously scattering off the plate ends and solve for the unstable resonance frequencies and temporal growth rates for long plates. We present a comparison between our computational results and the infinite plate theory. In particular, the resonance response of a moderately sized plate is shown to be in excellent agreement with our long plate analytical predictions.
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Das, Hangsa Raj, Rajesh Dey, and Sumanta Bhattacharya. "DESIGN OF RECTANGULAR SHAPED SLOTTED MICRO STRIP ANTENNA FOR TRIPLE FREQUENCY OPERATION FOR WIRELESS APPLICATION." In Topics in Intelligent Computing and Industry Design. Volkson Press, 2021. http://dx.doi.org/10.26480/etit.02.2020.169.172.
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This Paper represents the designing of the Tri- Band Rectangular Printed micro strip Antenna. One amongst the simplest feeding technique is employed i.e. coaxial feeding technique for feeding the antenna Tri band antenna is obtained by etching two quarter wavelength rectangular shaped slots inside the patch at the proper position to resonate over GSM, Bluetooth and Wi- MAX. The proposed antenna is realized on FR-4 dielectric substrate having a dielectric constant of 4.4 and loss tangent of 0.02, with dimensions of 46x38x1.6mm3. The design calculations are done for the frequency of 2.4 GHz. The designed antenna is simulated using EM simulation software CAD FEKO suite (7.0). The antenna covers the three bands of operation i.e. GSM (1.834-1.858GHz), Bluetooth (2.422- 2.487GHz), Wi-Max (3.519-3.583GHz) with reflection coefficient ≤-10dB. The overall simulation results shows that the antenna gives good impedance matching at desired frequencies with VSWR≤2.Also the radiation pattern, efficiency,gain and impedance for all four frequencies are investigated using simulation results.