Download or read book Hypersonic Flow Control Using Magneto hydrodynamics written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The focus of the present work is on the use of magneto hydrodynamics as a flow control device for supersonic and hypersonic vehicles. A three dimensional parabolized Navier Stokes solver was developed to take into account the effects of magnetic fields, by incorporating two magneto-hydrodynamic models. The modified solver was then used to study the effects of magneto-hydrodynamics on a variety of configurations, one study of which involved surrogate model based optimisation procedures. The first component of research involved validation of the low magnetic Reynolds number model model against well documented test cases. Good agreement with the nu- merical test cases for flows past a blunt body and a flat plate boundary layer flow, both in the presence of a magnetic field, was found. A novel application of the method of man- ufactured solutions to the simplified mapeto-hydrodynamic model was made to ensure its Accuracy. Assessment of the procedures used for numerical optimisation, were made against known closed-form solutions, and a theoretical axisymmetric body of revolution. An investigation for an optimal magnetic field configuration, for an over-sped Ram- jet intake was made. It was found that for a suitable choice of magnetic field strength, shock on lip could be achieved. Furthermore, for a suitable choice for the position of the magnetic field source, the design condition can also be satisfied using a weaker mag- netic field. Finally a study examining the use of magnetic fields for flows past a slender body were was performed. Given a suitably orientated dipole source, it was shown that the magnetic field can introduce asymmetries, for an otherwise symmetric flowfield, and thereby introduce side form on the missile.
Download or read book Hypersonic Flow Control Using Magneto hydrodynamics written by J. S. Bennett and published by . This book was released on 2007 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Low temperature Supersonic Flow Control Using Repetitively Pulsed MHD Force written by Munetake Nishihara and published by . This book was released on 2006 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The dissertation presents results of the low-temperature supersonic flow experiments using magneto-hydrodynamic (MHD) interaction. The M=3 flow in test section was ionized by a high voltage, short pulse duration, high repetition rate pulsed discharge. Transverse electric current was sustained by transverse DC discharge with the electric field applied in the direction perpendicular to the magnetic field direction. Flow temperature with and without 1.4 kW DC discharge inferred from the N2 emission spectra was T=180"20 K, indicating that 90% of the input power is stored in the nitrogen vibrational energy mode. Results of flow visualization using Mie scattering, combined with the results of boundary layer density fluctuation spectra measurements using the Laser Differential Interferometry (LDI) diagnostics, suggest that boundary layer turbulent transition occurs at stagnation pressures of P0~200-250 torr. LDI measurements detected an MHD effect on the ionized boundary layer density fluctuations. Retarding Lorentz force produced an increase of the density fluctuation intensity by up to 2 dB, compared to the accelerating force of the same magnitude applied to the same flow. Static pressure measurements in the MHD section showed that a retarding Lorentz force applied to the flow produced a static pressure increase of up to 17-20%, while accelerating force of the same magnitude applied to the same flow resulted in a static pressure increase of up to 5-7%. The fraction of the discharge input power going into Joule heat in nitrogen and dry air, [alpha]=0.1, has been inferred from the present experiments. Results of kinetic modeling of the crossed pulser-sustainer discharge in magnetic field are also presented. The model predictions are compared with the experimental discharge current-voltage characteristics and time-dependent current traces, both in the absence and presence of magnetic field, showing satisfactory agreement. In the presence of magnetic field, the model predicts electron and ion drift due to Lorentz force in the ExB direction. This effect creates a mechanism for the neutral species flow acceleration or deceleration by collisional momentum transfer from the ions to the neutrals. The results of the present work demonstrate feasibility of low-temperature MHD flow control in well-characterized laboratory experiments, for the first time.
Download or read book Magneto aerodynamic Hypersonics written by F. Witzeman and published by . This book was released on 2003 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Favorable interactions of electromagnetic fields and weakly ionized air for flow control have been recognized since the late 1950s. Potential applications of flow control to hypersonic flight vehicles were recently demonstrated by Russian research and concepts. The scientific knowledge base of this interdisciplinary area (i.e., fluid dynamics, electromagnetics, and chemical and thermal nonequilibrium gas dynamics) is extremely sparse. Therefore, controversy and even misunderstandings are abundant in the research community. This report documents the in-house research project that was initiated to develop a validated magneto-aerodynamic hypersonic analysis capability. The project combined experimental and computational simulations of high-speed gas dynamics in order to verify the scientific findings and define the usable scope for practical hypersonic flight. Sponsorship was provided by the U.S. Air Force Research Laboratory's Office of Scientific Research (AFOSR) as part of an Entrepreneurial Research Initiative over the period 3 January 1999 through 30 September 2003.
Download or read book Vortex Dominated Flows written by Denis L. Blackmore and published by World Scientific. This book was released on 2005 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt: Honoring the contributions of one of the field's leading experts, Lu Ting, this indispensable volume contains important new results at the cutting edge of research. A wide variety of significant new analytical and numerical results in critical areas are presented, including point vortex dynamics, superconductor vortices, cavity flows, vortex breakdown, shock/vortex interaction, wake flows, magneto-hydrodynamics, rotary wake flows, and hypersonic vortex phenomena.The book will be invaluable for those interested in the state of the art of vortex dominated flows, both from a theoretical and applied perspective.Professor Lu Ting and Joe Keller have worked together for over 40 years. In their first joint work entitled ?Periodic vibrations of systems governed by nonlinear partial differential equations?, perturbation analysis and bifurcation theory were used to determine the frequencies and modes of vibration of various physical systems. The novelty was the application to partial differential equations of methods which, previously, had been used almost exclusively on ordinary differential equations. Professsor Lu Ting is an expert in both fluid dynamics and the use of matched asymptotic expansions. His physical insight into fluid flows has led the way to finding the appropriate mathematical simplications used in the solutions to many difficult flow problems.
Download or read book Predictive and Reinforcement Learning for Magneto hydrodynamic Control of Hypersonic Flows written by Nilesh Vijay Kulkarni and published by . This book was released on 2007 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: Increasing needs for autonomy in future aerospace systems and immense progress in computing technology have motivated the development of on-line adaptive control techniques to account for modeling errors, changes in system dynamics, and faults occurring during system operation. After extensive treatment of the inner-loop adaptive control dealing mainly with stable adaptation towards desired transient behavior, adaptive optimal control has started receiving attention in literature. Motivated by the problem of optimal control of the magneto-hydrodynamic (MHD) generator at the inlet of the scramjet engine of a hypersonic flight vehicle, this thesis treats the general problem of efficiently combining off-line and on-line optimal control methods. The predictive control approach is chosen as the off-line method for designing optimal controllers using all the existing system knowledge. This controller is then adapted on-line using policy-iteration-based Q-learning, which is a stable model-free reinforcement learning approach. The combined approach is first illustrated in the optimal control of linear systems, which helps in the analysis as well as the validation of the method. A novel neural-networks-based parametric predictive control approach is then designed for the off-line optimal control of non-linear systems. The off-line approach is illustrated by applications to aircraft and spacecraft systems. This is followed by an extensive treatment of the off-line optimal control of the MHD generator using this neuro-control approach. On-line adaptation of the controller is implemented using several novel schemes derived from the policy-iteration-based Q-learning. The implementation results demonstrate the success of these on-line algorithms for adapting towards modeling errors in the off-line design.
Download or read book Hypersonic Magnetohydrodynamics with Or Without a Blunt Body written by R. H. Levy and published by . This book was released on 1964 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plasma Physics and Magnetohydrodynamics written by and published by . This book was released on 1963 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plasma Physics and Magnetohydrodynamics written by Defense Documentation Center (U.S.) and published by . This book was released on 1962 with total page 290 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The High Temperature Aspects of Hypersonic Flow written by Wilbur C. Nelson and published by Elsevier. This book was released on 2014-12-02 with total page 801 pages. Available in PDF, EPUB and Kindle. Book excerpt: The High Temperature Aspects of Hypersonic Flow is a record of the proceedings of the AGARD-NATO Specialists' Meeting, held at the Technical Centre for Experimental Aerodynamics, Rhode-Saint-Genese, Belgium in April 1962. The book contains the papers presented during the meeting that tackled a broad range of topics in the aspects of hypersonic flow. The subjects covered during the meeting include pressure measurements, interference effects, the use of wind tunnels in aircraft development testing, high temperature gas characteristics, boundary layer research, stability and control and the use of rocket vehicles in flight research. Aerospace engineers and aeronautical engineers will find the book invaluable.
Download or read book Fine Furniture Metalwork Pewter Clocks Sculpture Works of Art and Rugs and Carpets Including the Property of the Late Mr E Van Dam Rotterdam written by and published by . This book was released on 1989 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Magnetohydrodynamics written by Sergei S. Molokov and published by Springer Science & Business Media. This book was released on 2007-08-26 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book revises the evolution of ideas in various branches of magnetohydrodynamics (astrophysics, earth and solar dynamos, pinch, MHD turbulence and liquid metals) and reviews current trends and challenges. Uniquely, it contains the review articles on the development of the subject by pioneers in the field as well as leading experts, not just in one, but in various branches of magnetohydrodynamics, such as liquid metals, astrophysics, dynamo and pinch.
Download or read book Classic and High Enthalpy Hypersonic Flows written by Joseph J.S. Shang and published by CRC Press. This book was released on 2023-04-28 with total page 327 pages. Available in PDF, EPUB and Kindle. Book excerpt: Classic and High-Enthalpy Hypersonic Flows presents a complete look at high-enthalpy hypersonic flow from a review of classic theories to a discussion of future advances centering around the Born-Oppenheim approximation, potential energy surface, and critical point for transition. The state-of-the-art hypersonic flows are defined by a seamless integration of the classic gas dynamic kinetics with nonequilibrium chemical kinetics, quantum transitions, and radiative heat transfer. The book is intended for graduate students studying advanced aerodynamics and taking courses in hypersonic flow. It can also serve as a professional reference for practicing aerospace and mechanical engineers of high-speed aerospace vehicles and propulsion system research, design, and evaluation. Features Presents a comprehensive review of classic hypersonic flow from the Newtonian theory to blast wave analogue. Introduces nonequilibrium chemical kinetics to gas dynamics for hypersonic flows in the high-enthalpy state. Integrates quantum mechanics to high-enthalpy hypersonic flows including dissociation and ionization. Covers the complete heat transfer process with radiative energy transfer for thermal protection of earth reentry vehicle. Develops and verifies the interdisciplinary governing equations for understanding and analyzing realistic hypersonic flows.
Download or read book An Automated Design Optimization Tool for Electromagnetic Control of Hypersonic Flows written by Lei Tang and published by . This book was released on 2005 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: There has been computational work to analyze and control hypersonic flows using electromagnetic effects but no true effort has been pursued to automate the flow control process. The lack of a design framework that provides automated multi-disciplinary optimization (MDO) capabilities for this class of problems is the principal motivation for this work. This project develops the foundation of one of the principal components of such MDO environment. Control theory, which has already proved successful dealing with both aerodynamic shape and aero-structural optimization problems, is extended to magnetohydrodynamics (MND). The discrete adjoint approach emerges as the best suitable option to deal with the complex equations that govern MHD, and with the nature of the cost functions that may be used for relevant design problems. The equations governing the three-dimensional flow of a compressible conducting fluid in a magnetic field using the low magnetic Reynolds number approximation are solved with a gas-kinetic BGK scheme. Compared with the more conventional continuum CFD approach, a gas-kinetic CFD approach can be easily extended beyond the continuum regime.
Download or read book Development and Application of a Nonequilibrium Magnetohydrodynamics Code to Hypersonic Flow Power Generation written by Heath Lorzel and published by . This book was released on 2010 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recent Results in Theoretical and Experimental Hypersonics and Theoretical Magnetohydrodynamics written by CINCINNATI UNIV OHIO. and published by . This book was released on 1965 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: The theoretical investigation includes three dimensional hypersonic flow problems, shock interaction studies, weak interacting hypersonic flow over cones, hypersonic leading edge problems, wake problems, and an analysis of binary boundary layer problems. Additionally, a method is reviewed whereby the equations of a steady, twodimensional compressible, isentropic flow of a perfectly conducting gas with an aligned magnetic field can be reduced to those of the conventional non-magnetic case. The experimental portion of the investigation was conducted in a Mach 14, twenty-inch hypersonic wind tunnel. Topics investigated include the hypersonic wake problem, shock interaction, hypersonic flow over cones at low and high angles of attack, hypersonic inlet problems, hypersonic flow over flat plates with and without a glow discharge, and flow over delta wings at high angles of attack. Brief descriptions of the calibration of the above mentioned tunnel and evaluation of instrumentation used in conjunction with the tunnel are also included. (Author).
Download or read book Numerical Investigations of Magnetohydrodynamic Hypersonic Flows written by Andrew Guarendi and published by . This book was released on 2013 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerical simulations of magnetohydrodynamic (MHD) hypersonic flow are presented for both laminar and turbulent flow over a cylinder and flow entering a scramjet inlet. ANSYS CFX is used to carry out calculations for steady flow at hypersonic speeds (Mach number > 5). The low magnetic Reynolds number (“ 1) calculated based on the velocity and length scales in this problem justifies the quasistatic approximation, which assumes negligible effect of velocity on magnetic fields. Therefore the governing equations employed in the simulations are the compressible Navier-Stokes and the energy equations with MHD-related source terms such as Lorentz force and Joule dissipation. Turbulence effects are accounted for when applicable and multiple turbulence models are compared. The results demonstrate the ability of the magnetic field to affect the flowfield, and variables such as location and magnitude of the applied magnetic field are examined. An examination of future work is provided through the implementation of a semi-discrete central scheme in-house code toward the solution of the Orszag-Tang vortex system.
