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 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 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 Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Text Book on the Theory of the Motion of Projectiles the History Manufacture and Explosive Force of Gunpowder the History of Small Arms the Method of Conducting Experiments and on Ranges written by Great Britain. War Office and published by . This book was released on 1863 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Government Reports Annual Index written by and published by . This book was released on 1994 with total page 1688 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Projectile for a Rectangular Barreled Rail Gun written by Francisco M. Juanche and published by . This book was released on 1999-12-01 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Physics Department at the Naval Postgraduate School is developing a concept to overcome the problems that keep present rail guns from being practical weapons. The rails must be replaced often if the rail gun operation is to be continuous. Replacing the rails in present rail gun configurations is time consuming. The Physics Department's design concept uses a rectangular barrel as part of the solution to the problem of replacing the rails. The projectile will require flat surfaces to maintain electrical contact with the flat rails and aerodynamic stabilization because of the lack of angular momentum. This thesis develops one possible model of a projectile for a rectangular barreled rail gun, which could be used to replace the standard five-inch gun found on most warships. The proposed projectile is successfully modeled as a five inch projectile with flat areas planed onto opposite sides and long chord, short span fins attached in a cruciform configuration. The computer programs used to develop the projectile model are included to allow evaluation of alternate configurations.

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 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 Linear Drives for Industry Applications IX written by Yun Yue Ye and published by Trans Tech Publications Ltd. This book was released on 2013-09-10 with total page 2190 pages. Available in PDF, EPUB and Kindle. Book excerpt: LDIA2013 provides a forum for researchers, professionals and engineers from all over the world to present their latest researches and developments and to exchange information and experience in the fields of linear drives and other types of direct drive technologies. The scopes of the proceedings include but are not limited to: linear machine design and analysis, linear motor drive systems and control, actuators, maglev linear systems, linear motor applications, renewable energies associated with linear machines, and high-speed or low-speed/high-torque rotary machines and drives, etc.

Download or read book Electrical Electronics Abstracts written by and published by . This book was released on 1997 with total page 1860 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 International Aerospace Abstracts written by and published by . This book was released on 1996 with total page 940 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Experimental Validation of the SIMBAD Gun Dynamics Simulation Package for Flexible Saboted Long Rod Projectiles written by J. B. Hoyle and published by . This book was released on 1993 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: An experimental firing programme has been carried out using the RMCS 30mm Air Powered Gun to study the flexing of saboted long rod penetrators in-bore. A number of special two piece projectiles were developed, each with as nearly as possible the same mass, position of centre of gravity, pitch inertia, and band spacing, but with different rod diameters. A rigid one piece projectile was also developed, that had the same physical properties and band spacings. A refined technique for measuring the in-bore motion of the shot was introduced into the experimental facility. This technique enabled the pitch and yaw motion of the front end of the rod to be measured, thus producing data that could be directly compared with theoretical simulations. The technique made use of an optical displacement transducer mounted perpendicular to and down range from the muzzle. A light beam from this transducer was directed on to a mirror on the front of the projectile via a circular mirror in the path of the shot. This latter mirror was formed by stretching a thin aluminised membrane over an annulus, through which the projectile passed without damage. The displacement of the returning light beam from the projectile was then measured by the transducer, from which shot pitch and yaw motions could be calculated. Accurate measurement of the barrel profile was found to be necessary for the simulation work. This was achieved by pushing the rigid one piece shot slowly down the barrel, whilst measuring its pitch angle. The resulting data was then analysed to remove the gravity droop component, thus producing the barrel bend.

Download or read book Physics Briefs written by and published by . This book was released on 1989 with total page 832 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Collection of Technical Papers AIAA 85 1550 AIAA 85 1600 written by and published by . This book was released on 1985 with total page 614 pages. Available in PDF, EPUB and Kindle. Book excerpt: