Results 11 to 20 of about 56,125 (155)
Hypersonic Modes in Nanophononic Semiconductors [PDF]
Physical Review Letters, 2008 Frequency gaps and negative group velocities of hypersonic phonon modes in periodically arranged composite semiconductors are presented. Trends and criteria for phononic gaps are discussed using a variety of atomic-level theoretical approaches. From our calculations, the possibility of achieving semiconductor-based one-dimensional phononic structures ...
Hepplestone, SP, Srivastava, GP
openaire +4 more sources
Engineering nanoscale hypersonic phonon transport [PDF]
Nature Nanotechnology, 2022 Abstract Controlling the vibrations in solids is crucial to tailor their mechanical properties and their interaction with light. Thermal vibrations represent a source of noise and dephasing for many physical processes at the quantum level. One strategy to avoid these vibrations is to structure a solid such that it possesses a phononic stop band,
O. Florez +7 more
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An aerothermodynamic design optimization framework for hypersonic vehicles [PDF]
, 2018 In the aviation field great interest is growing in passengers transportation at hypersonic speed. This requires, however, careful study of the enabling technologies necessary for the optimal design of hypersonic vehicles.
Di Giorgio, Simone +3 more
core +1 more source
Code-Verification Techniques for Hypersonic Reacting Flows in Thermochemical Nonequilibrium [PDF]
Journal of Computational Physics, 425 (2021), 2020 The study of hypersonic flows and their underlying aerothermochemical reactions is particularly important in the design and analysis of vehicles exiting and reentering Earth's atmosphere. Computational physics codes can be employed to simulate these phenomena; however, verification of these codes is necessary to certify their credibility.
arxiv +1 more source
Research on the drag reduction performance induced by the counterflowing jet for waverider with variable blunt radii [PDF]
, 2016 Waverider will endure the huge aero-heating in the hypersonic flow, thus, it need be blunt for the leading edge. However, the aerodynamic performance will decrease for the blunt waverider because of the drag hoik.
Barakos, George N. +4 more
core +1 more source
The Climate Impact of Hypersonic Transport
, 2022 Abstract. Hypersonic aircraft flying at Mach 5 to 8 are a means for travelling very long distances in extremely short times and even significantly faster than supersonic transport (Mach 1.5 to 2.5). Fueled with liquid hydrogen (LH2) their emissions consist of water vapour (H2O), nitrogen oxides (NOx) and unburnt hydrogen. If LH2 is produced in a climate-
Johannes Friedrich Pletzer +4 more
openaire +2 more sources
Feedback Strategies for Hypersonic Pursuit of a Ground Evader [PDF]
arXiv, 2021 In this paper, we present a game-theoretic feedback terminal guidance law for an autonomous, unpowered hypersonic pursuit vehicle that seeks to intercept an evading ground target whose motion is constrained in a one-dimensional space. We formulate this problem as a pursuit-evasion game whose saddle point solution is in general difficult to compute ...
arxiv
Hypersonic Crossflow Instability
Journal of Spacecraft and Rockets, 2018 Under the auspices of NATO STO AVT-240: “Hypersonic Boundary-Layer Transition Prediction”, this paper describes the results of close collaborations among the authors toward the fundamental understa...
William S. Saric +6 more
openaire +3 more sources
Discontinuous Galerkin Methods for Hypersonic Flows [PDF]
arXiv, 2023 In recent years, high-order discontinuous Galerkin (DG) methods have emerged as an attractive approach for numerical simulations of compressible flows. This paper presents an overview of the recent development of DG methods for compressible flows with particular focus on hypersononic flows. First, we survey state-of-the-art DG methods for computational
arxiv
Generalized Newton-Busemann Law For Two-Dimensional Steady Hypersonic-limit Euler Flows Passing Ramps With Skin-Frictions [PDF]
arXiv, 2023 By considering Radon measure solutions for boundary value problems of stationary non-isentropic compressible Euler equations on hypersonic-limit flows passing ramps with frictions on their boundaries, we construct solutions with density containing Dirac measures supported on the boundaries of the ramps, which represent the infinite-thin shock layers ...
arxiv