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About: Afterburner is a(n) research topic. Over the lifetime, 811 publication(s) have been published within this topic receiving 5944 citation(s).

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Abstract: A new laser-driven ion acceleration mechanism has been identified using particle-in-cell (PIC) simulations. This mechanism allows ion acceleration to GeV energies at vastly reduced laser intensities compared with earlier acceleration schemes. The new mechanism, dubbed “Laser Break-out Afterburner” (BOA), enables the acceleration of carbon ions to greater than 2 GeV energy at a laser intensity of only 10 21 W/cm 2 , an intensity that has been realized in existing laser systems. Other techniques for achieving these energies in the literature rely upon intensities of 10 24 W/cm 2 or above, i.e., 2–3 orders of magnitude higher than any laser intensity that has been demonstrated to date. Also, the BOA mechanism attains higher energy and efficiency than target normal sheath acceleration (TNSA), where the scaling laws predict carbon energies of 50 MeV/u for identical laser conditions. In the early stages of the BOA, the carbon ions accelerate as a quasi-monoenergetic bunch with median energy higher than that realized recently experimentally.

251 citations

Journal ArticleDOI
TL;DR: It is shown that Otto cycle engine performance can be improved beyond that of the "ideal" Otto heat engine and a new kind of lasing without initial inversion is demonstrated.
Abstract: By using a laser and maser in tandem, it is possible to obtain laser action in the hot exhaust gases of a heat engine. Such a “quantum afterburner” involves the internal quantum states of the working molecules as well as the techniques of cavity quantum electrodynamics and is therefore in the domain of quantum thermodynamics. It is shown that Otto cycle engine performance can be improved beyond that of the “ideal” Otto heat engine. Furthermore, the present work demonstrates a new kind of lasing without initial inversion.

140 citations

Journal Article
Abstract: Breakout afterburner (BOA) laser-ion acceleration has been demonstrated for the first time in the laboratory. In the BOA, an initially solid-density target undergoes relativistically induced transparency, initiating a period of enhanced ion acceleration. First-ever kinetic simulations of the BOA in three dimensions show that the ion beam forms lobes in the direction orthogonal to laser polarization and propagation. Analytic theory presented for the electron dynamics in the laser ponderomotive field explains how azimuthal symmetry breaks even for a symmetric laser intensity profile; these results are consistent with recent experiments at the Trident laser facility.

126 citations

Journal ArticleDOI
Abstract: High temperature fuel cell technologies, solid oxide fuel cells (SOFCs) and molten carbonate fuel cells (MCFCs), are considered for their potential application to carbon dioxide emission control. Both technologies feature electrochemical oxidisation of natural gas reformed fuels, avoiding the mixture of air and fuel flows and dilution with nitrogen and oxygen of the oxidised products; a preliminary analysis shows how the different mechanism of ion transport attributes each technology a specific advantage for the application to CO2 separation. The paper then compares in the first part the most promising cycle configurations based on high efficiency integrated SOFC/gas turbine “hybrid” cycles, where CO2 is separated with absorption systems or with the eventual adoption of a second SOFC module acting as an “afterburner”. The second part of the paper discusses how a MCFC plant could be “retrofitted” to a conventional fossil-fuel power station, giving the possibility of draining the majority of CO2 from the stack exhaust while keeping the overall cycle electrical efficiency approximately unchanged.

121 citations

11 Mar 2002
Abstract: A fuel spraybar assembly for spraying fuel within a gas turbine engine. The spraybar assembly includes radial and lateral members that distribute fuel within the flowpath. In one embodiment two lateral members are located at the radially inward end of a radial member and generally form a "T" shape. Circumferentially spaced adjacent spraybars subdivide the flowpath into a plurality of circumferential combustion zone segments. In one embodiment the junction of the radial and lateral members provides a flameholding feature that stabilizes the combustion flame. In another embodiment, fuel is introduced non-uniformly within the afterburner resulting in thermal vectoring of the engine thrust.

95 citations

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