Download or read book An Approximate Analysis of Balloting Motion of Railgun Projectiles written by and published by . This book was released on 1991 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the final of three reports dealing with the in-bore balloting motion of a projectile fired from an electromagnetic railgun. Knowledge of projectile in-bore motion is important to its design and the design of the railgun. It is a complicated problem since many parameters are involved and it is not easy to determine the interacting relationships between them. To make the problem easier to understand it was analyzed on several levels. Beginning from the basic simple model which computed only the axial motion, more complicated models were introduced in upper levels that included the more significant lateral forces and gun tube vibration effects. This report deals with the approximate analysis of balloting motion. This model considers the effects of the propulsion force, the friction force of the projectile package (projectile and armature), air resistance, gravity, the elastic forces, and the projectile/ barrel clearance. To simplify the modeling, a plane motion configuration is assumed. Though the projectile is moving with a varying yaw angle, the axes of the barrel and the projectile package, and the projectile center of gravity are always considered in a plane containing the centerlines of the rails. Equations of motion are derived and solved. A sample computation is performed and the results plotted to give a clearer understanding of projectile in-bore motion.
Download or read book Basic Simple Modeling of Balloting Motion of Railgun Projectiles written by and published by . This book was released on 1991 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the second of three basic reports dealing with the in-bore balloting motion of a projectile launched in an electromagnetic railgun. The first report addressed axial projectile motion without cocking and was titled 'A Basic Single Model of In-bore Motion of Railgun Projectiles.' Understanding the inbore motion of a projectile is important to its design and its ability to hit a target with some effectiveness. Analysis of in-bore motion is a complicated problem since many parameters are involved and the interacting relationships between them must be determined. To make the problem easier to understand, it was analyzed on several levels beginning with the basic simple model which computed only the axial motion and followed by more complicated models in the upper analysis levels that included as many lateral forces and gun tube vibration effects as possible. This report deals with the second basic or zero level of balloting analysis. A basic simple model considering only the effect of the propulsion force, the friction force of the armature, and the clearance between the projectile and the barrel is presented. The computation of the axial projectile motion with a certain cocking angle is the goal of this analysis. Equations of motion are derived and solved. A sample computation with available data is performed and the results plotted to give a clearer understanding of balloting action.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Approximate Formulae for the Motion of Projectiles written by Peter Alexander and published by . This book was released on 1886* with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1991 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On Balloting of Projectiles written by Kevin S. Fansler and published by . This book was released on 1978 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: The possibility for balloting-energy growth is examined. The basic equations are developed and the important parameters for balloting motion are obtained and discussed. It is concluded from the analysis that balloting-energy growth can not occur for the balloting model assumed in the present treatment.
Download or read book Basic Simple Modeling of In Bore Motion of Railgun Projectiles written by and published by . This book was released on 1991 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: In an electromagnetic railgun a projectile encounters a complex force environment during launch. A thorough understanding of these forces is critical to projectile and gun tube design. There are many parameters involved and interacting relationships which must be determined. To better understand and establish the in-bore force models, we begin with a basic simple model which computes only the axial motion. More complicated models will be introduced in subsequent reports which will include lateral forces and gun tube vibration effects. This report deals with a very simple axial motion model. Only the effects of the propulsion force, projectile package mass, air resistance, and the friction forces are presented. Equations of motion are derived and solved. A sample computation with available data is performed and curves plotted to give clearer understanding of the results.
Download or read book Critical Velocity of Electromagnetic Rail Gun in Response to Projectile Movement written by Jerome T. Tzeng and published by . This book was released on 2002 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: A model is developed to investigate file dynamic response of an electromagnetic rail gun induced by a moving magnetic pressure during launch of projectiles. As the projectile velocity approaches a critical value, resonance can occur and cause high-amplitude stress and strain in the rail at the instant and location of the projectile's passage. In this study, governing equations of a railgun under dynamic-loading conditions are derived that illustrate a lower-bound critical velocity in terms of material properties, geometry, and barrel cross section. A study is then performed to show the effect of these parameters on the critical velocity of the barrel. Accordingly, the model that accounts for projectile velocity and gun construction can be used to guide barrel design.
Download or read book Critical Velocity of Electromagnetic Rail Gun in Response to Projectile Movement written by and published by . This book was released on 2002 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: A model is developed to investigate file dynamic response of an electromagnetic rail gun induced by a moving magnetic pressure during launch of projectiles. As the projectile velocity approaches a critical value, resonance can occur and cause high-amplitude stress and strain in the rail at the instant and location of the projectile's passage. In this study, governing equations of a railgun under dynamic-loading conditions are derived that illustrate a lower-bound critical velocity in terms of material properties, geometry, and barrel cross section. A study is then performed to show the effect of these parameters on the critical velocity of the barrel. Accordingly, the model that accounts for projectile velocity and gun construction can be used to guide barrel design.
Download or read book International aerospace abstracts written by and published by . This book was released on 1993 with total page 1060 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Acceleration of an Initially Moving Projectile written by Miguel Del GÃ1⁄4ercio and published by . This book was released on 2009-07-31 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the early 1980s, the principal mission for railguns required launch velocities in excess of 3 km/s. The focus of the research was centered on railguns employing plasma armatures. Significant efforts were expended on understanding the fundamentals of plasma armatures and their interaction with the bore. The temperatures associated with plasma armatures in railguns typically exceed 2 eV and, as a result, cause significant degradation in the bore materials leading to degradation of railgun performance. One parameter that seemed to ameliorate the effect of long dwell time was the use of a projectile injected into the breech of the railgun. This technique was often used with inert gas as the propulsive media. However, propellants were evaluated (1) and used to inject propellant-accelerated projectiles into the breech of a railgun (2). The burning propellant gases were insufficiently conductive to break down and form a plasma arc with 6000 V applied across the breech of the railgun. While no deleterious interactions were noted between the combustion products and plasma electrodynamics, the research was plagued with large variability in the injection velocity, obturation in the squarebore railgun, and reliable initiation of the plasma. All challenges were eventually solved. More recently, the mission for railguns has found utility using velocities
Download or read book Ballistics 2019 written by V. K. Saraswat and published by . This book was released on 2019-12 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book makes available original ballistics technology from around the world on a wide variety of weapons and their effects, including the design and trajectory/stability control of dozens of projectiles ranging from shells to missiles. The book's authors discuss the efficacy and development of propellants, munitions, and igniters and offer new approaches for modeling and testing. Also investigated in Volume 1 is gradient printing of energetic materials, and mechanical behavior of multiple types of explosives.Volume 2 offers research on impact and penetration data from projectile effects on surfaces ranging from natural phenomena such as water, to metallic plating and material-engineered armors. Recent advances in reactive fragments, which provide enhanced terminal effects, are presented. Detailed analysis of warhead mechanisms such as the formation and terminal effects of shaped charge jets are reported.Papers in these volumes were presented at a conference jointly organized and supported by the Aeronautical Society of India, Hyderabad Branch, India, and the International Ballistics Society.
Download or read book Government Reports Annual Index written by and published by . This book was released on 1991 with total page 1656 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the 33rd International Instrumentation Symposium written by International Instrumentation Symposium $(33rd : 1987 : Las Vegas, NNev.) and published by . This book was released on 1987 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Extending Russia written by James Dobbins and published by RAND. This book was released on 2019-04-11 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: As the U.S. National Defense Strategy recognizes, the United States is currently locked in a great-power competition with Russia. This report seeks to define areas where the United States can compete to its own advantage. It examines Russian vulnerabilities and anxieties; analyzes potential policy options to exploit them; and assesses the associated benefits, costs, and risks, as well as the likelihood of successful implementation.
Download or read book Out Of Control written by Kevin Kelly and published by Basic Books. This book was released on 2009-04-30 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: Out of Control chronicles the dawn of a new era in which the machines and systems that drive our economy are so complex and autonomous as to be indistinguishable from living things.
Download or read book Railway Noise and Vibration written by David Thompson and published by Elsevier. This book was released on 2008-12-11 with total page 535 pages. Available in PDF, EPUB and Kindle. Book excerpt: Railways are an environmentally friendly means of transport well suited to modern society. However, noise and vibration are key obstacles to further development of the railway networks for high-speed intercity traffic, for freight and for suburban metros and light-rail. All too often noise problems are dealt with inefficiently due to lack of understanding of the problem. This book brings together coverage of the theory of railway noise and vibration with practical applications of noise control technology at source to solve noise and vibration problems from railways. Each source of noise and vibration is described in a systematic way: rolling noise, curve squeal, bridge noise, aerodynamic noise, ground vibration and ground-borne noise, and vehicle interior noise. - Theoretical modelling approaches are introduced for each source in a tutorial fashion - Practical applications of noise control technology are presented using the theoretical models - Extensive examples of application to noise reduction techniques are included Railway Noise and Vibration is a hard-working reference and will be invaluable to all who have to deal with noise and vibration from railways, whether working in the industry or in consultancy or academic research. David Thompson is Professor of Railway Noise and Vibration at the Institute of Sound and Vibration Research, University of Southampton. He has worked in the field of railway noise since 1980, with British Rail Research in Derby, UK, and TNO Institute of Applied Physics in the Netherlands before moving to Southampton in 1996. He was responsible for developing the TWINS software for predicting rolling noise. - Discusses fully the theoretical background and practical workings of railway noise - Includes the latest research findings, brought together in one place - Forms an extended case study in the application of noise control techniques
