Download or read book Body Force of Plasma Actuator with Different Operating Conditions Using Phase resolved Approach written by Venur Tejas Alva and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma actuators are electric devices that can generate a flow of air without any moving parts. The salient feature of a plasma actuator is its ability to impart a body force in the region of the ionized air. The force produced is unsteady. A phase-resolved determination of force distribution is important to develop models that better approximate physical conditions for use in numerical simulations and design. Phase resolved study of the body force generated by the plasma actuator is performed experimentally using Particle Image Velocimetry. The primary objective of the present work is to study the ability of plasma actuators to transfer momentum to the air and the contribution of terms in the momentum equations used to compute the body force from the planar flow field measurements. The spatial and temporal evolution of the effect of the forcing by the actuator has been discussed with emphasis on the acceleration term.
Download or read book Flow Control Techniques and Applications written by Jinjun Wang and published by Cambridge University Press. This book was released on 2019 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: Master the theory, applications and control mechanisms of flow control techniques.
Download or read book Liste compl te de messieurs les d put s aux Etats G n raux de leurs adjoints suppl ants avec diff rentes observations les d liberations du Haut Clerg de la noblesse de Bretagne 1789 written by and published by . This book was released on 1789 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Investigation of Plasma Actuator Configurations for Flow Separation Control at Multiple Angles of Attack written by Thomas Kelsey West and published by . This book was released on 2012 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The primary objective of the study presented in this thesis was to analyze the effectiveness of aerodynamic plasma actuators as a means of active flow control over a low speed airfoil at multiple angles of attack each corresponding to two different flow separation mechanisms (i.e., laminar separation bubble and turbulent flow separation at stall conditions). Detailed parametric studies based on steady and unsteady Navier-Stokes simulations, modified to include the body force term created by the plasma actuator, were performed for a NACA 0012 airfoil at a chord Reynolds number of 105. In particular, parametric studies were performed to investigate the influence of the number, the location, the imposed body force magnitude (power input) and steady vs. unsteady operation of plasma actuators on the flow control effectiveness. First, the effectiveness of plasma actuators was studied when applied to the airfoil at a relatively low angle of attack, which involved the development of a laminar separation bubble (LSB). Next, the effectiveness of plasma actuators was analyzed at a high angle of attack where the stall of the airfoil occurs with a fully turbulent flow assumption. The results show that plasma actuators can provide significant improvement in aerodynamic performance for the flow conditions considered in this study. For LSB control, as much as a 50% improvement in the lift to drag ratio was observed. Results also show that the same improvement can be achieved using an unsteady or multiple actuators, which can require as much as 75% less power compared to a single, steady actuator. For the stalled airfoil case, as much as a 700% improvement in L/D was observed from a single, steady actuator. Note that this was achieved using a power input eight times higher than what was used for LSB control. Also, unsteady and multiple actuator configurations do not provide the same enhancement as the single, steady actuators. This was found to be due to the nature of the turbulent separation (trailing edge separation) at the stall condition that occurs for the selected airfoil and Reynolds number"--Abstract, leaf iii.
Download or read book Operation of the Aerodynamic Plasma Actuator at High Altitude written by Timothy Glen Nichols and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "A plasma actuator was operated at altitudes from 0 to 18288 meters to determine the mechanisms leading to decreased force production at low pressures. The actuator was driven with a 5 kHz sine wave and a peak to peak voltage of 13.4 kV at pressures of 760, 429, 321, 226, and 88 Torr. A passive measurement technique called the capacitive V-dot probe was adapted to the actuator in order to resolve the spatiotemporal evolution of the surface potential and electric field on the dielectric surface. At low pressures up to 20 times more plasma is present than at atmospheric conditions. Average force production is calculated and shown to decrease at lower pressures due to the fact that up to 88% of the plasma is created in regions where the electric field is approximately zero. The calculated average body force shows a slight increase up to a pressure of 429 Torr before trending to zero at lower pressures. Performing a power analysis shows that as pressure is decreased more power is used creating plasma than accelerating it, leading to a decrease in efficiency"--Abstract, leaf iii
Download or read book Recent Progress in Some Aircraft Technologies written by and published by . This book was released on 19?? with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Feedback Systems written by Karl Johan Åström and published by Princeton University Press. This book was released on 2021-02-02 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The essential introduction to the principles and applications of feedback systems—now fully revised and expanded This textbook covers the mathematics needed to model, analyze, and design feedback systems. Now more user-friendly than ever, this revised and expanded edition of Feedback Systems is a one-volume resource for students and researchers in mathematics and engineering. It has applications across a range of disciplines that utilize feedback in physical, biological, information, and economic systems. Karl Åström and Richard Murray use techniques from physics, computer science, and operations research to introduce control-oriented modeling. They begin with state space tools for analysis and design, including stability of solutions, Lyapunov functions, reachability, state feedback observability, and estimators. The matrix exponential plays a central role in the analysis of linear control systems, allowing a concise development of many of the key concepts for this class of models. Åström and Murray then develop and explain tools in the frequency domain, including transfer functions, Nyquist analysis, PID control, frequency domain design, and robustness. Features a new chapter on design principles and tools, illustrating the types of problems that can be solved using feedback Includes a new chapter on fundamental limits and new material on the Routh-Hurwitz criterion and root locus plots Provides exercises at the end of every chapter Comes with an electronic solutions manual An ideal textbook for undergraduate and graduate students Indispensable for researchers seeking a self-contained resource on control theory
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1998 with total page 920 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plasma Kinetics in Atmospheric Gases written by M. Capitelli and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: Emphasis is placed on the analysis of translational, rotational, vibrational and electronically excited state kinetics, coupled to the electron Boltzmann equation.
Download or read book Proceedings of the ASME Fluids Engineering Division Summer Conference 2006 Forums written by American Society of Mechanical Engineers. Fluids Engineering Division and published by . This book was released on 2006 with total page 1092 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Particle Image Velocimetry written by Ronald J. Adrian and published by Cambridge University Press. This book was released on 2011 with total page 585 pages. Available in PDF, EPUB and Kindle. Book excerpt: Particle image velocimetry, or PIV, refers to a class of methods used in experimental fluid mechanics to determine instantaneous fields of the vector velocity by measuring the displacements of numerous fine particles that accurately follow the motion of the fluid. Although the concept of measuring particle displacements is simple in essence, the factors that need to be addressed to design and implement PIV systems that achieve reliable, accurate, and fast measurements and to interpret the results are surprisingly numerous. The aim of this book is to analyze and explain them comprehensively.
Download or read book Design of Shape Memory Alloy SMA Actuators written by Ashwin Rao and published by Springer. This book was released on 2015-05-08 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: This short monograph presents an analysis and design methodology for shape memory alloy (SMA) components such as wires, beams, and springs for different applications. The solid-solid, diffusionless phase transformations in thermally responsive SMA allows them to demonstrate unique characteristics like superelasticity and shape memory effects. The combined sensing and actuating capabilities of such materials allows them to provide a system level response by combining multiple functions in a single material system. In SMA, the combined mechanical and thermal loading effects influence the functionality of such materials. The aim of this book is to make the analysis of these materials accessible to designers by developing a "strength of materials" approach to the analysis and design of such SMA components inspired from their various applications with a review of various factors influencing the design process for such materials.
Download or read book Progress in Propulsion Physics written by Luigi T. DeLuca and published by . This book was released on 2012 with total page 570 pages. Available in PDF, EPUB and Kindle. Book excerpt: La péface indique : "EUCASS (European Conference for Aero-Space Sciences) is a scientific association at the service of research scientists, engineers, and decision makers active in aeronautical and space sciences. EUCASS, which is an international nonprofit association under the Belgian law, addresses all topics of interest to aerospace, from research challenges to long-term programmes and prospective. It organizes regular conferences, workshops, and meetings. Its goal is to attract the best specialists from Europe and elsewhere, and to create a commonwealth of interest and challenges where in-formation and ideas circulate freely and swiftly, where the currently scattered European knowledge is exchanged much faster and cross-fertilised. EUCASS is the cradle that nurtures a friendly and lively community spirit among all players. It started its activities in 2005 by organizing the first-ever European conference in Moscow, followed at a biennial rate in Brussels and Versailles. In order to contribute to the dissemination of scientific knowledge, we have launched this EUCASS Book Series, the first and second volumes of which were dedicated to Propulsion Physics and presented a selection of the lectures given in Brussels in July 2007. EUCASS is organized in several permanent Technical Committees (TC). One of them is the Flight Physics TC. Within the broad EUCASS framework, the specificc purpose of the Flight Physics TC is to promote the technology, sciences, and arts of Flight physics and to help those engaged in these pursuits to develop their skills and those of their students. This third volume of the EUCASS Book Series on Advances in Aerospace Sciences is dedicated to Flight Physics. It comprises a selected collection of 43 papers presented at the 3rd European Conference for Aerospace Sciences held in Versailles, France, July 06-10, 2009. The current volume is the result of a long review process. About 1/3 of the total number of papers accepted for presentation at the conference was later selected by the volume editors, then edited by an international body of peer reviewers. The volume includes six chapters covering experimental, theoretical and numerical aspects of the fight physics: Chapter One Aerodynamics, Chapter Two Shock Interaction, Chapter Three High Enthalphy Flows, Chapter Four Heat Transfer, Chapter Five Aeroacoustics, Chapter Six Flow Control. To easily identify the material of interest, the reader is invited to consult the brief paper summaries compiled at the start of each chapter."
Download or read book Spacecraft Attitude Determination and Control written by J.R. Wertz and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 877 pages. Available in PDF, EPUB and Kindle. Book excerpt: Roger D. Werking Head, Attitude Determination and Control Section National Aeronautics and Space Administration/ Goddard Space Flight Center Extensiye work has been done for many years in the areas of attitude determination, attitude prediction, and attitude control. During this time, it has been difficult to obtain reference material that provided a comprehensive overview of attitude support activities. This lack of reference material has made it difficult for those not intimately involved in attitude functions to become acquainted with the ideas and activities which are essential to understanding the various aspects of spacecraft attitude support. As a result, I felt the need for a document which could be used by a variety of persons to obtain an understanding of the work which has been done in support of spacecraft attitude objectives. It is believed that this book, prepared by the Computer Sciences Corporation under the able direction of Dr. James Wertz, provides this type of reference. This book can serve as a reference for individuals involved in mission planning, attitude determination, and attitude dynamics; an introductory textbook for stu dents and professionals starting in this field; an information source for experimen ters or others involved in spacecraft-related work who need information on spacecraft orientation and how it is determined, but who have neither the time nor the resources to pursue the varied literature on this subject; and a tool for encouraging those who could expand this discipline to do so, because much remains to be done to satisfy future needs.
Download or read book An Introduction to Predictive Maintenance written by R. Keith Mobley and published by Elsevier. This book was released on 2002-10-24 with total page 451 pages. Available in PDF, EPUB and Kindle. Book excerpt: This second edition of An Introduction to Predictive Maintenance helps plant, process, maintenance and reliability managers and engineers to develop and implement a comprehensive maintenance management program, providing proven strategies for regularly monitoring critical process equipment and systems, predicting machine failures, and scheduling maintenance accordingly. Since the publication of the first edition in 1990, there have been many changes in both technology and methodology, including financial implications, the role of a maintenance organization, predictive maintenance techniques, various analyses, and maintenance of the program itself. This revision includes a complete update of the applicable chapters from the first edition as well as six additional chapters outlining the most recent information available. Having already been implemented and maintained successfully in hundreds of manufacturing and process plants worldwide, the practices detailed in this second edition of An Introduction to Predictive Maintenance will save plants and corporations, as well as U.S. industry as a whole, billions of dollars by minimizing unexpected equipment failures and its resultant high maintenance cost while increasing productivity. - A comprehensive introduction to a system of monitoring critical industrial equipment - Optimize the availability of process machinery and greatly reduce the cost of maintenance - Provides the means to improve product quality, productivity and profitability of manufacturing and production plants
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Windup in Control written by Peter Hippe and published by Springer Science & Business Media. This book was released on 2006-08-03 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: Actuator saturation is probably the most frequent nonlinearity encountered in control applications. Input saturation leads to controller windup, removable by structural modification during compensator realization and plant windup which calls for additional dynamics. This book presents solutions to the windup prevention problem for stable and unstable single-input-single-output and multiple-input-multiple-output (MIMO) systems.
